Bavaria Yacht Info

Member Forums => Modifications & Equipment => Topic started by: Salty on July 05 2018, 21:18

Title: Crazed Portlights and Hatches
Post by: Salty on July 05 2018, 21:18
Acrylic Deck Hatches and Portlight replacements on a Bavaria 36 from 2002.

THE PROBLEM.
The Lewmar acrylic deck hatches and portlights on my 2002 Bavaria 36 were so badly crazed, that by the winter of 2017/2018, I had decided that something needed to be done. As they were, the crazing had reached the stage where although the acrylics would allow light to enter the boat, they were pretty much hopeless for being able to see through.

Photo 1 shows how bad the portlights were, while photo 2 shows where adhesive strips applied to the outside of the main cabin hatch had prevented the areas under those strips from crazing.

HISTORY
I bought the boat from its original owner in January 2010. During its previous ownership, strips of non slip self adhesive tape had been applied to all of the deck hatches, and in those areas, the acrylic under the tape had not crazed at all. Conversely, those areas exposed to sunlight had suffered badly.

See photo 2

Something was causing the acrylic to craze, but only in those areas where light could pass through. The boat had two large and two small deck hatches, and of those smaller hatches, one appeared to have been changed at some time in the past. It is not clear which of the two was the original small hatch or which was the one that had been replaced. Obvious differences between one and the other was the type of latching handles provided where both of the handles on the starboard hatch penetrated through the acrylic while on the port side hatch one handle penetrated through while the second handle appeared to be glued to the acrylic.

A further difference was that the starboard small hatch had been covered with a plastic film as well as with non slip tapes, and that hatch had not suffered from any crazing. Unfortunately the plastic film had broken down,  and had not proved to be very long lasting. Fortunately, what was left of the film was relatively easy to remove without damaging the underlying acrylic. At this point the conclusion I’d come to was that sunlight was somehow causing the acrylic to craze. Elsewhere I’d read that stress can cause crazing, so it was possible that heat from the sun where the sunlight could pass through, was causing the acrylic to expand, thereby creating the stress that resulted in crazing. Maybe it was that, maybe it was something to do with UV light, perhaps it was something else, but the evidence was clear that where the sun was prevented or restricted from shining through the acrylic, no crazing took place.

RESEARCH
Enquiries were made from a vehicle window tinting firm to find out whether they knew of a plastic film that could be applied to the outside areas of the acrylics that would stop the sunlight from passing through, and which might last better than whatever had been applied to that starboard hatch.

Initially the window tinting firm advised against the idea on the basis that acrylic apparently tended to give off tiny amounts of gas when warmed by sunlight, and it was likely this that had caused the original film to bubble and break down. However, they checked with their supplier and were advised that a new plastic film was available which would allow those minute amounts of gas to permeate through the film without causing bubbles that might eventually lead to breakdown. So it was decided for my boat that any new acrylics would be covered with this specialised reflective plastic film.

Photo 3 shows the main cabin hatch where a new Lewmar Acrylic lens has been fitted. That lens had been covered with reflective film just prior to installation.

Photo 4 shows the same hatch from inside after the changes had been made.

A major area of concern however was the cost of replacement acrylics, and where in a comment seen elsewhere it had been suggested that when a boats hatch and portlight acrylics needed changing, that it was best to sell the boat to someone else and let them deal with the problem. I have no plans to sell my boat, at least not for several years to come, and so costings for replacement acrylics were looked at. What I found caused a rapid intake of breath followed by a pained exclamation of “ow much??!”
Because of the costs involved, I had no plans on changing any of the aluminium framework.

COSTS USING MANUFACTURERS REPLACEMENT PARTS
From a UK supplier, the costs were as follows:-
Lewmar large hatch acrylic lens, overall size 556 x 556mm complete with new rubber gasket, £197 each of which two were needed.

Small hatch acrylic size 556 x 276mm with rubber gasket at £174 of which one was needed, the other being ok.

Portlight acrylic size 633 x 159mm with Lewmar part number A081620H2 at £177 each of which six were needed.

The two small portlights facing into the cockpit from the two aft cabins were in fair condition so it was decided not to change these for the time being.

Estimated costs so far were
Two large hatches £197 x 2 = £394
One small hatch =. £174
Six portlights £177 each x 6 =£1062
Total £1630

Looking more recently at the SVB website in Germany suggests that acrylics sold there are significantly less expensive to buy than in UK, but then one has to add on the postage charges. Additionally their website, from what I’ve seen of it in regard to hatch and portlight replacement acrylics, is significantly lacking in detail. I’d need considerable reassurance from SVB before ordering to be certain that what I wanted was what I’d actually get.

FIRST ORDERS
My first order for acrylics was to replace a single large deck hatch and was followed up with an order for two sets of portlight acrylics. These were purchased from a UK supplier.

Initially I replaced the main cabin deck hatch, and my window tinting firm applied the acrylic friendly plastic film to both that new hatch and to the smaller starboard side hatch which was not being replaced. Their charge for this was £30 (Mates rate because it turned out I was a friend of a friend)!!

THE FIRST DIY BIT
Taking the deck hatch off and apart to remove the old and replace it with new acrylic was fairly straightforward although it was worthwhile taking a look at one of the “You Tube” videos to gain an insight into the removal of the hinge pins. Once those pins had been removed, this allowed the hinged part of the hatch to be taken off and removed to the cockpit where I could work on it. I also removed the two plastic locking handles as well as the small plastic thing that the friction stay attaches to. Looking now at separating the two aluminium side pieces that hold the acrylic lens in place, there are four small screws on each side which lock the two parts of the framework in place. Those screws were a little unwilling to undo, but nothing that very gentle use of an impact driver was not able to address. (One person I spoke to suggested that it was worth trying to tighten the screws first before undoing them, but I was lucky and they began to unscrew with just a couple of light hammer taps on the impact driver). It was only actually necessary to undo two adjacent screws on one or other side of the join on each side to allow the two sides to slide apart. To assist in the separation, I’d brought a couple of pieces of wood with me that day. One fairly substantial piece of wood was laid on the cockpit deck while the other which was about 800mm long with a cross section somewhere around 50mm x 20 mm was propped under the inner edge of the hatch against one side of the aluminium surround (not the sides with the joins in them) and the whole assembly with 800mm wood hand held in place was gently bumped down onto the other piece of wood I’d laid on the deck. The weight of the frame plus the acrylic lens it held within it did the trick and this was enough to start the process of separating the two halves of the frames on each of the deck hatches as they were worked on. A couple more bumps and the two sides of the frame were separated.
Title: Re: Crazed Portlights and Hatches
Post by: Salty on July 05 2018, 21:24
 Acrylic Deck Hatches and Portlight replacements on a Bavaria 36 from 2002. The second part continuing from the previous post.

PROBLEMS !
The portlights however were another matter. Lewmar have modified the port light hinges and catches such that those fitted to new replacement acrylics will not fit the old aluminium hinge supports. Because of this change, new aluminium supports for both the hinges and catches have to be fitted. Removing the old supports is not an easy task, and is made even more difficult by the fact that these supports are held in place with stainless (I think!) screws secured into the external aluminium frame. Over the years there had been some corrosion of the aluminium around those stainless screws making them impossible to undo. Checking around all of the frames where portlights were to be replaced confirmed that many of those screws were not going to be undone easily if at all! If they could not be undone, this would mean having to buy new frames to fit the replacement acrylics, and an already expensive job looked like it was just about to double in price !!

Initially I was unaware of the changes that Lewmar had made, and my supplier had not advised of any differences in regard to those hinge and catch fittings. So when trying to fit the new portlights I found that those differences would not allow the new portlights to shut. Checking with an electronic digital calliper revealed that the measurement from the outside of the portlight to the innermost point of the new hinges was 2mm greater than that of the old hinge system, 29 mm instead of 27 mm and at the time my UK supplier had not provided me with a full kit of replacement parts. The full replacement kit was remedied within the price I’ve quoted above and, with considerable difficulty, I was able to remove the old aluminium hinge and catch brackets and fit the newly supplied ones. I now had two new portlights in place plus one new hatch acrylic, and a smaller existing hatch acrylic which had been smartened up with a covering of reflective film.

See photos 1 and 2 below of the hinge and catch supports

So now being confronted with a possibility that I might not be able to replace my remaining portlights, I began looking at what alternatives there might be.

ALTERNATIVES
Firstly in regard to the second large deck hatch that I wanted to change, having removed one I now had a template which I could take to a local plastics firm to ask them to make me a new replacement. This was done for considerably less than the £197 charged for the first deck hatch, saving me well over £100 off the cost, but with a down side that I had to re-use the original seal rubber. The original seal rubber fortunately was in reasonable order, and so it was re-used. Over the last month rain showers have been very few, but liberal use of several buckets of sea water over the replaced hatch has shown no signs so far of any water leakage.

See photo 4 below.

Secondly in regard to the portlights, even if the acrylic part could be supplied, a major difficulty was immediately evident in that none of the boat window manufacturers that I approached were able to offer a replacement for the Lewmar portlights, let alone one that might be more cost effective than what I’d paid so far. I’m guessing that the main stumbling block was the fact that the plastic hinges and catches used are actually stuck to the existing acrylic windows, and I didn’t know if they could be successfully removed or not. If they were to be re-used, they would have to be very carefully removed, and up to the time of writing this I have not seen these plastic hinges or catches available to buy anywhere. Furthermore, at the time I had no idea what kind of plastic they were made of, or what type of adhesive could be used to stick them back on to a new acrylic portlight.

INVESTIGATION AND EXPERIMENTS
Having already purchased and fitted two Lewmar replacement portlights I now had two old portlights left that I could experiment with. Initially I cut around each hinge with a hack saw, but that was not an ideal solution. So I tried a different approach. With the portlights clamped down onto a flat surface to support the acrylic, and with the hinge and catch fittings uppermost, that with a 6mm carpenters chisel pointed into the “U” shaped area between the acrylic prongs that plastic hinges are attached to and initially at the seam between one of the acrylic prongs and the plastic hinge or catch, that gentle tapping of the chisel with a light hammer resulted in the plastic fittings separating from the acrylic. Gentle tapping here is the watch word, and the chisel needs to be reasonably sharp. The one I used was not razor sharp, but I wouldn’t want to argue with someone wielding it in an unfriendly way either !! First one end of the fitting being worked on began to lift and at that point I turned my attention to the other end. Gentle tapping worked better than impatience, and most of the fittings came away without taking any of the acrylic with them, but often leaving some traces of the adhesive attached either to the acrylic or to the fittings. It was really important at the time that the acrylic was very securely clamped at either end of the hinge or catch fitting that I was about to try to remove in order to ensure that the old portlight acrylic was left intact for use as a template for its replacement.

MORE DIY
Having determined the most efficient method for removing the hinges and catches, most of the removed fittings came away with some of the old adhesive still attached, but careful use of the same chisel and a few light hammer taps enabled removal of the remaining adhesive. I was now left with an intact acrylic template plus six fittings made of ‘er “some kind of plastic !!” Someone more versed in plastics might be able to tell me exactly what kind of plastic those hinges and catches are made of, but please no guesses.

See photos 1 & 2 below.

A BIT MORE RESEARCH
Having removed all of the hinges and catches from one of the old portlights I now spent some time trying to figure out what type of adhesive to use to stick those fittings to the new portlight acrylics that a local manufacturer was about to make up for me. In the meantime I had discussed the matter with several users and suppliers of plastic adhesives and had come across a Structural Acrylic Adhesive called “Partite 7300 (MA300) consisting of a product called Methacrylate. This costs a little under £10 on eBay from a seller called “e-Teck”for a 50ml twin pack of the adhesive and hardener. This I used in a test securing of one hinge to the leftover old acrylic portlight. To say that I was impressed, is a gross understatement, indeed it is so strongly attached that I believe it has more permanency than the proverbial brick built outside toilet !!

Partite 7300 is a two part adhesive mixed at a ratio of one to one. The seller, whom I phoned and spoke to, advised that it had a working time of about ten seconds from start of mixing to getting the fitting held in place before it began to cure. So if you intend to stick six fittings into place on an acrylic portlight blank, you need to be pretty quick. Having used the adhesive it was my opinion from my first mix that there was probably a little more leeway than ten seconds, and so some twenty or so seconds after my first test gluing of a hinge in place, I gave the remnants of the mix another stir and placed the metal mixing tool that I’d used onto those remnants. An hour or two later when I went to have a look at my handiwork, that tool could not be separated from the mixing palette, though I didn’t try too hard at that stage as the mix may not have have cured. I did try very very much harder next day, and couldn’t remove either the hinge or the mixing tool from where each had been stuck.
I’d found a satisfactory adhesive, but it’s application considering its limited working life was still an area for concern.
In discussions with E-Teck, they were extremely helpful by the way, they suggested I buy from them a £16 glue dispenser and some mixing tubes. These tubes fit to the outlet from the twin tube adhesive container, and as the adhesive passes through the mixing tube it arrives at the nozzle ready for use. On the basis that each fitting would take probably a tubefull of adhesive, I figured that so long as I didn’t waste any time I’d be able to apply adhesive to the first fitting and press it correctly into place while the adhesive on its way down the mixing tube remained within its working life ready for the next fitting. So don’t hang around once you start !! My theory worked and after all of the fittings were attached to a port light the used mixing tube was then discarded and the cover replaced onto the twin nozzle of the adhesive container. I marked both the nozzle and the cover on one side so that the cover was always put back on the same way round in order not to contaminate the adhesive outlets.

IN FOR A PENNY!!
Four portlight acrylic blanks were ordered from the plastics firm. The old portlight from which I’d carefully removed the hinges and catches was used to make a CAD drawing, presumably for controlling their machinery in order to cut out the replacement acrylics. A few days later I collected the blanks and set about preparing each of the fittings in readiness for gluing into place. While waiting for the blanks to be made I spent time working on the removed hinges and catches in order to clear away as much of the old adhesive that remained. The carpenters chisel and hammer were ideal for this, and finally checking that the measurements of 27mm referred to earlier were retained. They weren’t, but I managed to get between 27 and 27.5 mm which I thought the seal rubber would likely accommodate. It did, just !! But I’m going to get another 0.5mm taken out of where those fittings attach to the acrylic in any future blanks that the plastic firm makes.

ASSEMBLING THE PARTS
Where the hinge and catch fittings were to be placed, the acrylic had been machined to provide a recess, and you will see from the photos that each of the plastic fittings was shaped so that they would fit to the ends of the horns projecting from the top and bottom edges of each portlight. It was important that the distance between the outside face of the portlight and the innermost point on each hinge or catch was 27mm as measured earlier in this description. Mine in fact were just slightly more at around 27.5mm making the portlights a bit of a tight fit when they are shut, but they didn’t leak when given the three buckets of sea water test !!

See photo 5 below
The photo here shows one of the new replacement acrylic portlights with plastic fittings securely glued in place and fitted into one of the portlight openings on my boat. The original protective plastic film was left in place for the time being, but it will of course be removed at final fitting.
In addition to the discrepancy referred to above, the hinge and catch positions at each end also need to be moved closer to the centre hinge and catch positions by about 1mm. Minor adjustments were made with the use of a file, and all four portlights were fitted into place and secured, albeit temporarily as they were then removed to go to the auto tinting firm for reflective film to be attached. The size adjustments will be advised to the plastics firm so that they can modify their CAD drawing. In addition I will also ask them make me one more new portlight blank that I can then make up and check that it fits without further need for adjustment, and will then hold it onboard as an “in case of emergency” spare.

CLEAR OR TINTED ACRYLICS ?
The hatch and portlight blanks that I have had made up have been in clear rather than tinted acrylic as this was what the plastics firm either had in stock or was readily able to obtain. I don’t know whether a tinted acrylic would involve different costs, but clearly if only one or two small parts were needed, the plastics firm would need to recover the cost of a sheet of tinted plastic if there was little likelihood of being able to use the rest of the sheet of material.

As mentioned earlier, I’ve had a car window tinting firm fit a reflective film to my acrylics in order to reflect sunlight, and this also serves to provide a form of tinting visible from inside. From outside the hatches and portlights appear reflective. This increases internal privacy while on a marina berth, as well as reducing the transmitted heat from the sun, thereby keeping the cabin cooler. That reduction in sunlight will I suspect also reduce fading of internal fabrics and of the mahogany finish to the internal woodwork. Hopefully it will also stop the acrylics from crazing, but the longevity of the coating remains to be seen.

SUMMARY,
on the plus side:-
1. What I’ve done so far, has got around the need to remove and replace those aluminium hinge and catch fittings which Lewmars modified replacement acrylics have demanded, but which are so difficult to take out from the older boats where corrosion has resulted in the stainless screws becoming seized in place.
2. It has very significantly reduced the cost of fitting replacement acrylics on those boats that have been fitted with Lewmar hatches and Portlights, such that when the time comes to replace those acrylics, that “Selling the Boat” should no longer be a consideration !!
3. It has removed the awful crazed acrylics and has allowed me the pleasure of being able once again to see out from within.
4. At the completion of this exercise I will have one spare ready to fit portlight carried onboard for that emergency occasion.
5. The new portlights are made from slightly thicker material, so arguably they may be stronger and more resilient than the originals, but no guarantees!
6. My plastics firm have CAD drawings for controlling their machines and machining such that should readers want to try doing things themselves, that replacement blanks for the two sizes of acrylics I have ordered from them so far will be readily available.
7. The plastic film provides for greater privacy while on a marina berth, as well as reflecting the sun and thereby helping to keep the cabin interior cooler, and hopefully prevent or reduce the rate at which the acrylics start to craze.

On the negative side :-
1. I have no assurance that the acrylics made up partly by my plastics firm and partly by me are strong enough to survive seriously bad weather, but I’m very very impressed with the strength I’ve seen in them so far.
2. Should one want to remove the hinges and catches from one of the newly made up portlights, they will come apart as I’ve already checked that, but I can assure the reader that it will be nowhere near as easy a job to take them apart as they did from the original portlights.
3. For those of you who may wish to go down this route you will note that I’ve not been specific yet about my actual costs for the acrylics, but after I have spoken again to the plastics firm I will hopefully have a figure for individual hatches or portlights to be able to report back, likewise also for film covering if it should be required.
4. For those of you that want to go down the same route, you have the somewhat daunting task of removing those plastic fittings from your old portlights, cleaning them up to remove most of the old adhesive, and then sticking them to your new portlight blanks. Not a job for the faint hearted, but very much lighter on the pocket.
5. Can’t think of anything else, but I’m sure you the readers can.

The large deck hatch acrylic held on CAD refers to one made by Lewmar where the hatch size is given as 556 x 556mm with two openings for securing handles on one side and with a separate oval opening opposite to enable a plastic fitting to go through to which a friction clamp controls and holds the hatch open to where you have set it. The actual acrylic size for this hatch is 520 x 520mm overall, or 500 x 500mm from inside frame edge to inside frame edge when viewed from outside.
The portlight acrylic held on CAD is similar in size to a Lewmar portlight bearing the part number A081620H2, and measures 633mm x 159mm to the ends of the horns or prongs that hold the hinges or catches in place. The nominal depth of the portlight opening is 131mm.

If anyone should be interested in ordering replacements for the above sizes of hatch or portlight, send me a private message and I’ll discuss your requirements with the plastics firm and get back to you. Should you have different sizes of hatch or portlights that you want to replace, the first person ordering would need to send an acrylic sample so that it can be accurately measured up for its replacement, costed, and of course carriage charges would be involved for all orders.

July 3 2019 update regarding the adhesive.
Browsing the adhesive sellers website a few minutes ago, I saw they had an almost identical adhesive namely Partite 7310(MA310) which has a longer curing time of 15 - 18 minutes. This would take the pressure of getting all of the hinges and catches in place before the adhesive became unworkable. See the last photo below for details. The adhesive is available through eBay.


Title: Re: Crazed Portlights and Hatches
Post by: Yngmar on July 19 2018, 22:13
Thanks Salty, excellent write-up.

I feel very glad my boat came with Rutgerson portlights and Gebo hatches  ;D
Title: Re: Crazed Portlights and Hatches
Post by: Odysseus on July 20 2018, 11:12
Well done Salty, good article, another crap product with a work around.

Odysseus.
Title: Re: Crazed Portlights and Hatches
Post by: MarkTheBike on July 20 2018, 16:07
Fantastic article, Salty, very well done. Tons of info and clearly explained. How's the writer's cramp?
Title: Re: Crazed Portlights and Hatches
Post by: Salty on July 21 2018, 20:00
Thanks Yngmar, Odysseus and Mark, your comments are greatly appreciated. I wish I could have done a YouTube video of the DIY bits, as the DIY stuff is really not difficult to do if one is reasonably handy with a small hammer and a narrow bladed chisel. The difficult bit was to take the plunge and have go, knowing that if it all went pear shaped that I was about to wreck a usable (even if badly crazed) portlight. As it happened the hinges and catches came off easily, and I got really lucky in finding a suitable adhesive.
I have yet to go back to the plastics firm to get them to modify their CAD drawing of the portlight lense, and that modification will change the portlights from needing some minor trimming to a straightforward fit. The deck hatch fitted perfectly first time, so they can be turned out whenever needed. The one remaining small deck hatch will be done over the next winter.
Thanks again guys.
Title: Re: Crazed Portlights and Hatches
Post by: Ricd on July 30 2018, 11:58
Thanks Salty, excellent write-up.

I feel very glad my boat came with Rutgerson portlights and Gebo hatches  ;D

Interesting like you my hatches are Gebo and ports are Rutgerson (2000 B34).  Just last week we were rafted against an identical B34 (2002 build) that had Lewmar hatches and i assume likewise ports as the external frame was a dull brushed aluminium rather than SS. The owner asked how we maintained ours which are very slightly crazed only while the Lewmars were like frosted glass.  Answer was we don't really It must be down to the different manufacturer choice of acrylic?
Title: Re: Crazed Portlights and Hatches
Post by: Salty on July 30 2018, 17:34
Yes, that is interesting as to why some acrylics craze like mad while others don’t. One of my  Sailing friends has a Dufour 41 of the same age or slightly older than my B36, and his portlights and Hatches are all perfect while mine were like frosted glass, until I changed them !!
Title: Re: Crazed Portlights and Hatches
Post by: MarkTheBike on July 30 2018, 20:48
...The deck hatch fitted perfectly first time, so they can be turned out whenever needed...

Hi Salty

I've had a look at my deck hatches and they are a different style, with hinges either side of the centreline rather than a hinge in the middle. Having worked with the acrylic now, would you think a 'blank' (i.e. without the hinge cutout) is modifiable using hand tools - drills, chisel, file, rasp, sandpaper, etc? If so, what information would the plastics company need to make them, and in what form? Drawing? Spreadsheet? CAD file? Back-of-an-envelope? Also, at some point, I have to replace my companionway hatch as it's damaged. Again, do you think they could supply? These can be jobs for the winter but it would be good to find out.

Interestingly, both my hatches (Lewmar, like Ricd's) are crazed but none are of the portlights (Rutgerson) or companionway (?) acrylics.

Cheers  :)
Title: Re: Crazed Portlights and Hatches
Post by: Yngmar on July 30 2018, 20:49
All of ours are tinted acrylic. Maybe that protects the acrylic itself from UV damage? It certainly protected the interior varnish, which is still fine except for a few areas that are worn from use.
Title: Re: Crazed Portlights and Hatches
Post by: MarkTheBike on July 30 2018, 21:17
All of ours are tinted acrylic. Maybe that protects the acrylic itself from UV damage? It certainly protected the interior varnish, which is still fine except for a few areas that are worn from use.
Interesting, Yngmar. Mine are also dark tinted but, as mentioned earlier, look like a smashed windscreen so it didn't help in my case . My failed acrylics are Lewmar, is that the same for anyone else or are there different manufacturers whose acrylics go crazy?
Title: Re: Crazed Portlights and Hatches
Post by: Salty on July 30 2018, 22:46
Hi Mark,
I’m a little confused. You say your hatches are Lewmar, and that suggests to me that they must be similar to mine, but then you say they are different. Any chance you could take some photos please both inside and out.

Like Yngmar’s hatches, my hatches and portlights were all dark tinted, smoky rather than green, but the tinting had not prevented the acrylic from crazing. I don’t know if Lewmar produce hatches or portlights where there is a choice in regard to how dark the tinting may be. I’d assumed the choices were simply smoky, green or clear, full stop. What did stop the crazing was the non-slip tape that had been stuck to the outside of the hatches and in one case some plastic film stuck to one of the hatches.
Title: Re: Crazed Portlights and Hatches
Post by: Ricd on July 31 2018, 14:10
...The deck hatch fitted perfectly first time, so they can be turned out whenever needed...

Interestingly, both my hatches (Lewmar, like Ricd's) are crazed but none are of the portlights (Rutgerson) or companionway (?) acrylics.

Cheers  :)

Correction, my hatches are Gebo (not crazed).  The ones that were crazed on the identical boat we rafter to were lewmar.

Also both my hatches and portlights are tinted (blown) and likewise intenal woodwork has not been bleached by the sun.
Title: Re: Crazed Portlights and Hatches
Post by: MarkTheBike on July 31 2018, 14:13
Hi Salty
Only pic I have at the moment but am going down later so will do some better ones. I think both hatches are identical but will confirm dimensions, etc. asap...
Cheers
Title: Re: Crazed Portlights and Hatches
Post by: MarkTheBike on July 31 2018, 15:38
Correction, my hatches are Gebo (not crazed).  The ones that were crazed on the identical boat we rafter to were lewmar.

Oops, serves me right for skim-reading. Silly me...
Title: Re: Crazed Portlights and Hatches
Post by: Salty on August 01 2018, 08:07
Hi Mark,
From your photos you have Lewmar hatches. They are hinged in the same way as mine, but on your larger hatches you have a different stay arrangement for propping the hatch open. Subject to overall measurements being the same, the plastics firm would be able to make new blanks for you that did not have a cut out area for the friction stay that I have. Also if you were to make a paper template of the entire upper surface of the hatch acrylic within the boundary of the aluminium frame, and showing the exact size, location and shape of the cut out for your hatch stay and the precise location and shape of the cutouts for your securing handles, then I’m sure they could produce new acrylics to suit your large hatches. In regard to the smaller oblong hatches, I notice that yours are not fitted with securing handles that go right through the acrylic. Assuming they are the same size as my oblong hatches then they should be easy enough to produce without the holes for the handles, but while your handles would need to be glued back on, what I’m not sure about is whether the acrylic has a machined out recess for those handles to fit into. One of my smaller oblong hatches has a combination of one through fitted securing handle and one glued on handle, while the other identically sized hatch has two handles that both penetrate through the acrylic. Don’t ask why, the boat was purchased second hand, and there was no history provided with it. As it was an ex charter boat I do suspect there may have been some movement of portable parts between boats and between agreement to buy and handover dates 🤢

Going on to Yngmars comment about the tinted acrylics having prevented fading of the interior surfaces, my companionway hatch has a smoky brown tint, but the wooden companionway bulkheads either side of the steps are both noticeably faded. The problem here however is that because the hatch would have been open for part of the time its not possible to be entirely sure whether the hatch tint provided protection or not. Strangely neither the companionway hatch or door on my boat are crazed !!!!
Title: Re: Crazed Portlights and Hatches
Post by: MarkTheBike on August 01 2018, 12:27
Hi Salty
Yes, as you say, the stay is a bar fixed to the acrylic that runs through a friction handle attached to the coachroof frame. I'll take more photos of the inside to post up, and check how the small hatch handles are attached. Not got long down there today but will do drawings/dimensions asap.

All my acrylics are tinted brown and there is no discernable fading inside anywhere (after 12 yrs in Guernsey and 5 yrs in Plymouth) so I suspect it's the tint that stops fading and the manufacturer's choice of acrylic that determines whether they craze or not. My companionway hatch and 'door' are tinted, have always faced south and are not crazed. Also, the interior wood nearby doesn't appear faded at all but the hatch is left closed for long periods. From what I remember of our past charter boats, those are always left open unless it's tipping down or nighttime.

I'm curious about one of your earlier comments that some film on the acrylic had prevented crazing. Was it a clear film? If so, I'm intrigued.
Title: Re: Crazed Portlights and Hatches
Post by: Jeff Jones on August 01 2018, 22:25
Hi Mark, just seen your photo above... we have the same boat only a year apart (yours newer) My hatches have Gebo labels  and the outside handles are different to mine.. and no crazing at all..

it defiantly seems that Bavaria just fit what ever hardware they got the best supply deal on at the time

Jeff
Title: Re: Crazed Portlights and Hatches
Post by: Salty on August 02 2018, 07:38
Hi Salty
Yes, as you say, the stay is a bar fixed to the acrylic that runs through a friction handle attached to the coachroof frame. I'll take more photos of the inside to post up, and check how the small hatch handles are attached. Not got long down there today but will do drawings/dimensions asap.
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I'm curious about one of your earlier comments that some film on the acrylic had prevented crazing. Was it a clear film? If so, I'm intrigued.

Hi Mark,
If you measure the dimension of the upper visible surface of the hatch between the aluminium framework surrounding the acrylic, I can compare it with the measurement of my old acrylics which I’ve not yet thrown away (I’m going to try polishing to see if I can remove the crazing that way, but I’m not hopeful).
As for the film covering that had been placed over one of my hatches before I bought the boat, I’m really not sure whether it was clear or tinted, the remaining pieces were small where it had almost completely broken down, and in removing the stuff I didn’t keep or examine what came off. It may have been tinted, but that’s only a guess.
Title: Re: Crazed Portlights and Hatches
Post by: MarkTheBike on August 02 2018, 10:55
A quick note -
  Jeff, that adds to my thoughts about manufacturers and acrylic choice. I hadn't thought about it before but as you say, our boats are almost identical so Bav were fitting hardware to hand rather than to plan.
  Salty, I'll upload details/photos later but whilst there yesterday, I had a really close look at the crazing and now I'm not so sure that the cracks are caused by UV. When I put my finger behind the acrylic, I could clearly see the crazing is shallow (< 1mm) and so wonder if it's possibly caused by heat-induced stress of the outer surface rather than UV. Assuming acrylic is an insulator, the sun side would heat more than the interior side, generating internal stresses and so the integral strength of the acrylic is more important than its UV resistance. Possible??? Does anyone out there have a boat 10+ yrs old, in a cooler environment with Lewmar hatches that are crazed?
  In the interim, the visible acrylic dimension from the outside L & W is 514mm. Outside of that is a 4mm rubber bead and then the aluminium frame. Hope this all helps...
Title: Re: Crazed Portlights and Hatches
Post by: Symphony on August 02 2018, 16:31
Thanks Salty, excellent write-up.

I feel very glad my boat came with Rutgerson portlights and Gebo hatches  ;D

Interesting like you my hatches are Gebo and ports are Rutgerson (2000 B34).  Just last week we were rafted against an identical B34 (2002 build) that had Lewmar hatches and i assume likewise ports as the external frame was a dull brushed aluminium rather than SS. The owner asked how we maintained ours which are very slightly crazed only while the Lewmars were like frosted glass.  Answer was we don't really It must be down to the different manufacturer choice of acrylic?

I suspect like my 2001 37 your original hatches were Rutgerson like the ports but were a disaster as they leaked around the seal the acrylic was set in. They were all replaced under warranty with Gebo and then new boats used Lewmar. It took a year for mine to be replaced and the table still has a crack in the veneer caused by the puddles of water!
Title: Re: Crazed Portlights and Hatches
Post by: Salty on August 03 2018, 08:02
.
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  In the interim, the visible acrylic dimension from the outside L & W is 514mm. Outside of that is a 4mm rubber bead and then the aluminium frame. Hope this all helps...

Hi Mark,
Your hatches are of different dimensions from mine where the external visible acrylic dimension is 500 x 500mm with an overall dimension measured once removed from the aluminium frame of 519 x 519mm. In this case the only safe thing to do would be to remove the acrylic in order to provide an accurate template for the supplier to match. I did this with my hatch and covered the opening with a sheet of plywood bolted through to a temporary timber strong back placed under the cabin top. The plywood was then covered over with a sheet of heavy duty plastic from a garden or builders waste bag in order to keep the rain and hopefully any light fingered visitors out.
Title: Re: Crazed Portlights and Hatches
Post by: MarkTheBike on August 03 2018, 10:58
Hi Salty
I had a feeling that might be the case as soon as I measured it. OK, well this will have to be a back-burner for a few weeks as life, once again, is interrupting me!
Cheers all, ufn
Title: Re: Crazed Portlights and Hatches
Post by: Salty on August 04 2018, 19:04
For those of you that read through my original postings on this subject, you may remember that I mentioned in regard to covering the acrylics with plastic film to prevent possible UV damage from sunlight, and that the window tinting firm had initially advised that acrylic gave off tiny quantities of gas which until then the ordinary films could not cope with. Well today I read an article posted on the BBC News App about some research carried out by Dr Sarah Jeanne Royer. In her research it seems that most, if not all plastics give off methane and other ozone depleting gasses.

In her article the following statement was found
“What's causing these emissions?
In short it's the Sun. Solar radiation acts on the surface of plastic waste. As it breaks down, it becomes cracked and pitted, these defects increase the surface area of plastic available.”

At the time she was only looking into what was happening with waste plastics, but my contention is that it must be happening to all plastics, and starting from the moment of manufacture.

Perhaps we should start to insist on Portlights and Hatches being made from suitably toughened glass which won’t craze and won’t give off ozone depleting gasses, but then isn’t the whole boat hull made from plastic?  🤢
Title: Re: Crazed Portlights and Hatches
Post by: Ricd on August 05 2018, 11:06
For those of you that read through my original postings on this subject, you may remember that I mentioned in regard to covering the acrylics with plastic film to prevent possible UV damage from sunlight, and that the window tinting firm had initially advised that acrylic gave off tiny quantities of gas which until then the ordinary films could not cope with. Well today I read an article posted on the BBC News App about some research carried out by Dr Sarah Jeanne Royer. In her research it seems that most, if not all plastics give off methane and other ozone depleting gasses.

In her article the following statement was found
“What's causing these emissions?
In short it's the Sun. Solar radiation acts on the surface of plastic waste. As it breaks down, it becomes cracked and pitted, these defects increase the surface area of plastic available.”

At the time she was only looking into what was happening with waste plastics, but my contention is that it must be happening to all plastics, and starting from the moment of manufacture.

Perhaps we should start to insist on Portlights and Hatches being made from suitably toughened glass which won’t craze and won’t give off ozone depleting gasses, but then isn’t the whole boat hull made from plastic?  🤢

Having said all that Salty, from the posts here the Gebo hatches are not crazing to any significant degree while the Lewmar ones appear to be frosted after only a few years.  That points to a variable in the materials used by the two companies.  No need for glass, just Gebo acrylic.  My hatches ar 18 years old and have little crazing.
Title: Re: Crazed Portlights and Hatches
Post by: Twhitt on August 13 2018, 08:43
Hi, we have a B38 Holiday from year 2000. It has Gebo hatches and ports, and all are well crazed, maybe due to Mediterranean sun?

I am looking to replace them all, and have a catalogue from Gebo of hatches and replacement acrylic supplied to Bavaria.

Back out to boat next month, so will check sizes and get prices. They also provide a service where you can send them the accrylics and they will replace including moving over all fittings. Probably OK if you only have one to replace but not ten!
Title: Re: Crazed Portlights and Hatches
Post by: Yngmar on August 16 2018, 15:59
Hi, we have a B38 Holiday from year 2000. It has Gebo hatches and ports, and all are well crazed, maybe due to Mediterranean sun?

Incidentally we've just had a charter B44 come in next to us here in Sicily. Must've been built within a year of our boat and has the same Gebo deck hatches as ours. Ours are fine, while theirs are crazed really badly.

So I think the key here is the much greater UV exposure, as this boat looks to have spent its life being chartered around here. Perhaps some exterior hatch covers may be worthwhile?
Title: Re: Crazed Portlights and Hatches
Post by: MarkTheBike on August 16 2018, 16:46
...Perhaps some exterior hatch covers may be worthwhile?...

Mandatory if you have Lewmar and are anywhere south of the Arctic Circle!  :)
Title: Re: Crazed Portlights and Hatches
Post by: Salty on August 16 2018, 19:00
I have some hatch covers, though I rarely used them at best and they haven’t seen the light of day now for several years, but while hatch covers are readily available, does anyone actually make covers for portlights?
Title: Re: Crazed Portlights and Hatches
Post by: Kibo on August 21 2018, 17:36
Hi Salty

We had some hatch covers made by a canvas maker who made our bimini and dodger and a bow cover. Pretty simple square (or oblong!) of fabric made to size with a drawstring around the edge. We use Sunbrella fabric since we are in high UV area.

Only really needed for the deck hatches which get the main UV blast all day  Our hatches are flush fit compressions seal type that have a ridge around the edge to the covers fit on them quite well. Not sure about other designs of hatch?

I think you can also buy proprietary hatch covers from Lewmar etc too....

Thanks for your original post. Very interesting and helpful.
Title: Re: Crazed Portlights and Hatches
Post by: Salty on September 06 2018, 21:23
Hi Salty
.
Thanks for your original post. Very interesting and helpful.

Thanks for the kind words Ian

However in regard to the comment about hatches getting the maximum exposure, my portlights were just as badly crazed as the deck hatches, or arguably were even worse because the deck hatches at least had strips of non slip tape stuck to them which had protected the acrylic under those tapes. The portlights had no protection at all.
Title: Re: Crazed Portlights and Hatches
Post by: Kibo on September 07 2018, 04:08
Thanks Salty

Interesting. On my boat all my "vertical" lights are OK so far but I will certainly keep an eye out.

The problem is on the new Vision models the hull and topside lights are all fixed/bonded in so not much chance to change them or protect them since they are flush with the hull.
Title: Re: Crazed Portlights and Hatches
Post by: SaltyLass on September 15 2018, 15:05
The portlight acrylic held on CAD is similar in size to a Lewmar portlight bearing the part number A081620H2, and measures 633mm x 159mm to the ends of the horns or prongs that hold the hinges or catches in place. The nominal depth of the portlight opening is 131mm.

If anyone should be interested in ordering replacements for the above sizes of hatch or portlight, send me a private message and I’ll discuss your requirements with the plastics firm and get back to you. Should you have different sizes of hatch or portlights that you want to replace, the first person ordering would need to send an acrylic sample so that it can be accurately measured up for its replacement, costed, and of course carriage charges would be involved for all orders.

I will need to check the part number on the Portlights (Bav36 / 2003) but I would be very interested in trying this. I have sourced replacements from Lewmar (6 for about £930 in total) but this business of the extra 2mm and the screws worries me. I do not want to spend the thick end of £1000 and find that the holes do not match up
Title: Re: Crazed Portlights and Hatches
Post by: Salty on September 15 2018, 19:06
The thing to do is to remove each portlight, one at a time by undoing the hinge bolt. With the portlight removed you now have clear access to get at the aluminium hinge and catch brackets. These are small “L” shaped aluminium parts held in place by a small countersunk screw. The screw I think is made from stainless steel, and with that comes the first difficulty in that they can be seized into the aluminium portlight frame. So probably before doing anything at all you should spray some easing oil, WD40 or similar onto each of those particular screws and leave them for a week or two, topping up the easing oil occasionally. There is a lightweight plastic trim provided around the internal perimeter of the Lewmar portlights, and these should be eased gently away before you start.
Once the easing oil has had chance to work try once only with a cross head screwdriver to remove those screws. If that doesn’t work and they don’t undo easily, don’t try it again. Instead I used an impact driver with a relatively lightweight hammer and was able to remove all of the bracket screws on two portlights only, the screws on the remaining four large portlights were totally unwilling to undo and hence my need to look at alternatives. If you are able to remove those screws on all of the portlights then you can go down the route of spending £1000 if you want. If those screws do not undo then your choices are to do as I did, or to buy new portlights complete with frames.
The new portlight acrylics that Lewmar provide have different size hinge pins, different size plastic hinges and catches as well as those “L” shaped brackets, and the new acrylics will not fit and close using the old brackets.
If you are able to remove the securing screws for those brackets, your next problem will be to remove the brackets from the slot through which they are placed. This is also not an easy task and is likely to make you think of all kinds of uncomplimentary things to say about the way they have been fitted.
New Lewmar portlights should come with a complete new set of those brackets, so don’t worry too much about the condition of the old brackets once you have got them out as the new brackets are much easier to put in place than to remove. I had to resort to using a small file to ease removal of the old brackets on the two windows I replaced with new Lewmar acrylics.
I didn’t mess around with the four remaining portlights and went ahead with my DIY option.
Good luck.
Title: Re: Crazed Portlights and Hatches
Post by: SaltyLass on September 15 2018, 20:23
Where exactly was the extra 2mm mismatch? I am a little confused about that.

Thanks for all the other tips. I will look at it carefully in the next couple of days
Title: Re: Crazed Portlights and Hatches
Post by: Salty on September 16 2018, 05:59
From my original post-
“Checking with an electronic digital calliper revealed that the measurement from the outside of the portlight to the innermost point of the new hinges was 2mm greater than that of the old hinge system, 29 mm instead of 27 mm.”
Essentially you have a thickness of acrylic to which the plastic hinges and catches are stuck. The section through the hinges forms an inverted “V” shape on the inside of the portlight. Measure from the outside of the portlight acrylic to the point of the “V” on the inside, and it should measure 27mm on your old portlights. Similarly with the catches but excluding the moveable part of the catch operating lever.
If you need further explanation I’ll take some photos when I’m back home next week to try to make things clearer, I’m just about to head off to the Southampton Boat Show now, and I’m pushed for time.
Title: Re: Crazed Portlights and Hatches
Post by: WAArete on November 12 2018, 18:36
mark the Bike,
 Interestingly, your forward hatch is mounted reverse of mine... Guess, you are prepared for larger seas then mine ....
Title: Re: Crazed Portlights and Hatches
Post by: MarkTheBike on November 13 2018, 17:42
mark the Bike,
 Interestingly, your forward hatch is mounted reverse of mine... Guess, you are prepared for larger seas then mine ....

Possibly (although I hope never to test that fully!) but there are times when I wish it opened to the fore. When everything's aft, there's no airflow inside at all and it can get pretty stuffy in summer... same problem when parked and tipping it down from astern.  :P
Title: Re: Crazed Portlights and Hatches
Post by: Spirit of Mary on November 13 2018, 22:24
My boat (BAV 38 2003) was used by a sailing academy in Gibraltar and needed to be RYA certified. The RYA required the forward hatch to be reversed. When at anchour this is a big disadvantage, specially in hot mediterranean weather. It is not easy to get a refreshing airflow inside.
Also the RYA required all the windows and hatches to be replaced because of crazing and too less transparancy (after 5 years of use).
Title: Re: Crazed Portlights and Hatches
Post by: Yngmar on November 14 2018, 20:19
Ours was mounted the "safe" way too. I turned it around last year because ventilation at anchor is critical in hot summers. It did leak a few drops (water pressure through the seal) when we were going upwind in a gale with whole waves over the bow, but I'm still glad I turned it around.

Alternatively you can get a wind scoop, but that's one more piece of gear to rig every time you drop the hook.
Title: Re: Crazed Portlights and Hatches
Post by: WAArete on May 27 2019, 03:59
The thing to do is to remove each portlight, one at a time by undoing the hinge bolt. With the portlight removed you now have clear access to get at the aluminium hinge and catch brackets. These are small “L” shaped aluminium parts held in place by a small countersunk screw. The screw I think is made from stainless steel, and with that comes the first difficulty in that they can be seized into the aluminium portlight frame. So probably before doing anything at all you should spray some easing oil, WD40 or similar onto each of those particular screws and leave them for a week or two, topping up the easing oil occasionally. There is a lightweight plastic trim provided around the internal perimeter of the Lewmar portlights, and these should be eased gently away before you start.
Once the easing oil has had chance to work try once only with a cross head screwdriver to remove those screws. If that doesn’t work and they don’t undo easily, don’t try it again. Instead I used an impact driver with a relatively lightweight hammer and was able to remove all of the bracket screws on two portlights only, the screws on the remaining four large portlights were totally unwilling to undo and hence my need to look at alternatives. If you are able to remove those screws on all of the portlights then you can go down the route of spending £1000 if you want. If those screws do not undo then your choices are to do as I did, or to buy new portlights complete with frames.
The new portlight acrylics that Lewmar provide have different size hinge pins, different size plastic hinges and catches as well as those “L” shaped brackets, and the new acrylics will not fit and close using the old brackets.
If you are able to remove the securing screws for those brackets, your next problem will be to remove the brackets from the slot through which they are placed. This is also not an easy task and is likely to make you think of all kinds of uncomplimentary things to say about the way they have been fitted.
New Lewmar portlights should come with a complete new set of those brackets, so don’t worry too much about the condition of the old brackets once you have got them out as the new brackets are much easier to put in place than to remove. I had to resort to using a small file to ease removal of the old brackets on the two windows I replaced with new Lewmar acrylics.
I didn’t mess around with the four remaining portlights and went ahead with my DIY option.
Good luck.
Salty,
 I saw your diy post. However, given your vast knowledge on Lewmar. You say, the friction pins for the hinges were either too big or too small? I found the same thing today upon trying to swap out a replacement Hatch. The pins just ever so slightly oversized for the receiver. My question, back to port lights. Lewmar seems to have multiple models for our Bavarias. New standard and old standard, plus #1 and #2 for its new standard. How does one determine which one has?
 Thanks once again,
 Roland
Title: Re: Crazed Portlights and Hatches
Post by: Salty on May 27 2019, 11:45
I saw your diy post. However, given your vast knowledge on Lewmar. You say, the friction pins for the hinges were either too big or too small? I found the same thing today upon trying to swap out a replacement Hatch. The pins just ever so slightly oversized for the receiver. My question, back to port lights. Lewmar seems to have multiple models for our Bavarias. New standard and old standard, plus #1 and #2 for its new standard. How does one determine which one has?
 Thanks once again,
 Roland

Hi Roland,
Your old portlights assuming they are the same as mine were, should have the identification number A081620H2 moulded into the acrylic near to one of the long edges of the portlight.

If they have that number on them then you need to purchase the Mark2 or New Standard portlight replacement acrylic. I understand that the replacement acrylic should be marked 361341990, but I can’t confirm that until I go back to my boat next weekend.

Be aware that you cannot mix and match parts from the old acrylics with the new because while the new acrylics will fit within the opening provided by the aluminium frame, the hinges and catches have different dimensions, and the hinge pins for the new portlights are of 5mm diameter instead of 4mm originally used, and the “L” shaped brackets used for the hinges and latches have a longer vertical leg to enable the larger plastic hinges and latches to be fitted.

Getting the old stainless screws that secure these “L” shaped brackets out of the aluminium frame can be a pig of a job because of the corrosion that occurs between stainless steel and aluminium. If you are lucky and have the right tools to do the job and are able to remove those stainless screws, the next problem comes in removing the “L” brackets from the slot into which they were placed. Inside the cabin there are plastic headlining mouldings which may partially cover those slots through which the L brackets are placed and which make removal of the brackets very difficult. Here you need a small thin flat file to remove the plastic where it overlaps the edges of the slot, though possibly a sharp Stanley Knife might do the trick as it is only some 1 or 2 mm of plastic that actually needs removal. The area will be covered by the portable plastic moulding you have already removed to gain access to the area, so you don’t need to be concerned about the area being marked with what you are doing.

Good luck with the task, and that’s a great part of the world to be sailing in.
Title: Re: Crazed Portlights and Hatches
Post by: Clivert on May 27 2019, 14:16
When you leave the boat put hatch covers on.
It will stop the uv damaging them.
Uv is a killer long term on anything
Title: Re: Crazed Portlights and Hatches
Post by: Salty on May 27 2019, 22:16
When you leave the boat put hatch covers on.
It will stop the uv damaging them.
Uv is a killer long term on anything

That’s a good idea, but how do you protect the portlights? ....They go crazy too !!
Title: Re: Crazed Portlights and Hatches
Post by: Salty on June 03 2019, 21:01
Where exactly was the extra 2mm mismatch? I am a little confused about that.
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The measurement from the outer face of the acrylic portlight to the innermost point on either the hinge or the catch on the opening Lewmar portlights fitted to boats such as my B36 of 2002 was mentioned as being 27mm. However in order to try to give a clearer indication of where that measurement should be taken, I took a photo of one of my old portlights where the hinges and catches had not been removed, and I refer readers who may be interested to the photo below. Here you can see the outer face of the acrylic portlight and, for want of a better expression, the horns that form part of the shape of the acrylic portlight to which the hinges or catches are glued. Measuring as shown by the yellow arrows between the outside face of the acrylic to the innermost point on each hinge or catch should be 27mm. However on the new replacements provided by Lexmark, and because of their modifications to the original set up, that measurement is now 29mm. To accommodate the extra 2mm Lewmar have had to provide longer “L” shaped brackets because if the original brackets are re-used it will not be possible to shut their new portlight replacements.
Title: Re: Crazed Portlights and Hatches: Glass anyone?
Post by: s/y Susanne on June 06 2019, 12:00
Salty's write up, and his willingness to answer supplementary questions both deserve serious praise. So thanks to Salty and all who have contributed to this subject.

I have the same problem with crazed, UV damaged, plastic portlights and hatches ( B44/2002) and have to admit that, in the case of portlights, I really would prefer to replace them with fixed portlights. We never open ours anymore as they always leaked after being opened.
 
Has anyone experimented with toughened glass and a fixed retaining bezel and seal? There appears to be enough through-fixings in the frame to allow substantial and even compression of gaskets to hold in place a glass lens. It would require fabrication of an aluminium or s/s inner bezel and would involve dispensing with the  white plastic clip-on inner trims but from an engineering "feel" I would rather trust such a portlight against re-glued plastic clips.

Glass could be toughened, laminated or both.

Any ideas anyone?
Title: Re: Crazed Portlights and Hatches
Post by: Clivert on June 06 2019, 21:17
When we leave the boat we put hatch covers on.
Reduces uv damage.
Title: Re: Crazed Portlights and Hatches: Glass anyone?
Post by: Salty on June 06 2019, 21:20
Salty's write up, and his willingness to answer supplementary questions both deserve serious praise. So thanks to Salty and all who have contributed to this subject.
.
.
Has anyone experimented with toughened glass and a fixed retaining bezel and seal? There appears to be enough through-fixings in the frame to allow substantial and even compression of gaskets to hold in place a glass lens. It would require fabrication of an aluminium or s/s inner bezel and would involve dispensing with the  white plastic clip-on inner trims but from an engineering "feel" I would rather trust such a portlight against re-glued plastic clips.

Glass could be toughened, laminated or both.

Any ideas anyone?

Firstly, thank you for your kind words, they are much appreciated.

In regard to toughened or laminated glass, or a mixture of both, I think that checking the after market manufacturers of replacement windows would show more than one that are capable of providing fixed windows with glass rather than plastic lenses. In my case I had wanted to try to replace like with like, and I spoke to several such firms at last years Southampton boat-show, and several were interested in what I’d done, but whether they thought it viable from a business point of view, I have no idea, but I’m sure that some of them did fixed pane non opening glass windows. Whether they were toughened or laminated I must admit I didn’t ask.
Title: Re: Crazed Portlights and Hatches
Post by: Salty on June 06 2019, 21:54
When we leave the boat we put hatch covers on.
Reduces uv damage.

Using hatch covers on the hatches is a good move, but as I said in an earlier reply, how do you protect your portlights? These are also exposed to the sun and are equally vulnerable to UV damage. On my boat the portlights were every bit as badly damaged from crazing as were the hatches.

I have had a special reflective film that was specifically designed for use on plastic windows applied to my hatches and portlights, and after one full year there is no crazing yet on any of the acrylic lenses to which it was fitted. Also, and while it’s not much help in the UK, it does help to reduce cabin temperatures during the summer months and so would be of benefit to those whose boats are kept in warmer climates.

In response to WAArete and my posting on May 27. Roland, I have now checked the the two genuine Lewmar portlight replacements fitted to replace two of old my cabin portlights, and contrary to the number I had suggested in the posting that day and which appears to be just some stock code used by a UK seller of replacement Lewmar products, the marking on the replacement Lewmar portlights includes the following number 30081609 P 14F16 and with the word Lewmar imprinted above the numbering. On these replacement windows the Lewmar marking is almost, but not quite invisible, but it does help to open the portlight and move it around a bit in order to allow the light to reveal the markings.

Title: Re: Crazed Portlights and Hatches
Post by: Salty on July 03 2019, 11:05
Hi All,
This is to advise you of an update I have added to the second posting under this heading.
In regard to the adhesive used, while visiting the sellers website today, I noticed that they now had a longer curing version of the glue I had used to stick the hinges and latches to the acrylic portlights. This adhesive has a curing time of 15 - 18 minutes, so that would take all of the pressure off getting the hinges and latches all properly into place before the glue became unworkable.
The adhesive, Partite 7310(MA310) is available through eBay, or direct from the seller whose telephone number is shown on the attached photo below, and currently is priced under £9 per 50ml cartridge. As before it comes in a twin tube cartridge with the two components being mixed together after being dispensed at a ratio of 1/1.
Title: Re: Crazed Portlights and Hatches
Post by: ancanc on October 15 2019, 11:56
Hi, Salty,

i have the same "crazed portlights" problem, i have to change 10 Lewmar Portlights on my bavaria 44 2003. I would like to ask you some questions:
- "Lewmar have modified the port light hinges and catches such that those fitted to new replacement acrylics will not fit the old aluminium hinge supports." Do you know when it was changed? My acrylics have the numbers A015 (small) and A016 (long).
- "Four portlight acrylic blanks were ordered from the plastics firm." - approx. how much did you pay for the acryllics?

You wrote in one of your posts, that the german SVB had good prices, unfortunately not anymore, they have just doubled the price for the long acrylic i would need, it costs now EUR 285, some month ago was about EUR 140...

Regards: Andras


Title: Re: Crazed Portlights and Hatches
Post by: Salty on October 15 2019, 20:32
Hi Andras and welcome to the forum.

The long portlights on my Bavaria 36 built in 2002 carry the number A081620H2, and so it is most likely they are a different size from yours which carry a different number. Essentially the acrylic used for my long portlights measures 634mm long by 131mm across the opening width but excluding the horns used for securing the catches and hinges. If you include those horns, then the measurement goes up to a maximum of 159mm.

The cost for each portlight cut to shape and including the machined out areas where the hinges and catches were to fit was approximately £70 each. The overall thickness of the acrylic used for the replacement portlights was slightly more than that used in the original Portlights, but that thickness was not critical whereas the thickness of the acrylic in the areas where the hinges and catches were to fit was critical in order to ensure that the overall thickness measured from the outside surface of the portlight to the innermost point in way of the hinge pins was no more than 27mm after assembly and glueing.

A further point in regard to the acrylic sheet material they used to provide my portlights and skylights is that the acrylic was not tinted at all. I don’t know how much more my supplier might want to charge for a tinted acrylic, but I can imagine they would want to recover their cost for the size of plastic sheet they would have to buy in to provide the required tint on the number of portlights required.

If your portlights are somewhat similar in size to mine, and if you were happy to accept clear non tinted acrylic, then I would anticipate my supplier could provide you with portlights at a similar price to that which I paid, and that would allow you to continue to use your existing aluminium brackets without the need to remove the brackets from the aluminium portlight frame.

In regard to the date when Lewmar changed over from the old size fittings to the new size, I’m sorry, but I don’t know or cannot recall when that happened. I suspect however that it was several years after both your boat and mine were built.

I gather that you and your boat are based in Hungary, so that if you wanted to send your portlights over here for my supplier to manufacture, there would be some postal and other charges involved.
Title: Re: Crazed Portlights and Hatches
Post by: ancanc on October 15 2019, 22:37
Hi Salty,
and thanks for the fast reply.
I made a mistake in the acrylic numbers, they are the same as yours... you can see them on my attached pictures. A0815 and A0816 plus some numbers - they somehow represent the manufacturing date according to Lewmar.
You are right, my boat lies in Hungary on the lake Balaton but i am living in Düsseldorf/Germany.
Last summer i tried to sand and polish one portlight acrylic, because i thought that the "scratches" were only on the outer surface of the acrylic and they could be removed or minimized. If you take one old acrylic in your hand and you look through while moving it, it seems that there is a small fraction of the thickness  with the scratches and the bigger part to the inner side is not affected... All i achieved was that i now have one matt acrylic.. i moved it to the toilet and said to my wife : i wanted it so, it helps privacy... I am still not really convinced that is not the case, maybe one should sand off more material (0.1 - 0.2 mm).     
The fresh water of the lake is helping against corrosion issues - i tightened a few hinges and all screws were loose and not corroded, so if needed i could change the required parts. Not cheap, 8 long (á EUR 240) and 2 short (á EUR 170) acrylic plus 10 assembly kits (á EUR 65) (the inner ones are in great shape...)
I have fabricated some blinds for the portlights too, evolved the "design" for three years..  It seems to be reliable now. I cut out 630x130 mm from a white carrier sheet (0,15mm thick) in the form of the acrylic, then i apply a self-adhesive also very thin reflecting layer onto it (it looks from the outside like bad quality mirror) Theese materials are used for making billboards.  Usually if i am on the boat i keep them off the acrylic but if i leave the boat i apply theese "blinds" onto the acrylics: open the portlight, make the blind a bit wet with a sponge, put it on the acrylic and smooth it out. The water makes it stick to the acrylic so i can close the portlight. The whole blind is about 0.2-0.25 mm thin so it is not making the portlights to leak at all. I will do some pictures next weekend - maybe some of the forum members are interested. I have blinds on the hatches too, but this can be done easily. This helps me keep the heat (and UV) out of the boat. Sometimes, when it is really hot i let the blinds on the acrylic on the sunny side.
To be honest i find theese portlight acrylics are a very bad "certificate" for Lewmar, on my earlier 1999 Bav 34 the Gebo portlights and hatches are still in a very good shape.... Lewmar probably knows the problem, but instead of helping us with "moderate" prices for the parts - they make a big business out of it.
Andras
Title: Re: Crazed Portlights and Hatches
Post by: ancanc on October 22 2019, 16:58
Hi Salty,

i measured the thickness of the acrylic+hinge, a have a reading of 27mm too. What is the thickness of your original and new acrylic itself?
I made some pictures of the "blinds" or covers for the portlights and the hatches.
These covers protect the acrylics, keep the temperature lower inside the boat and prevent the furniture from bleaching.
Regards:
Andras
Title: Re: Crazed Portlights and Hatches
Post by: Salty on October 22 2019, 19:45
Hi Salty,

i measured the thickness of the acrylic+hinge, a have a reading of 27mm too. What is the thickness of your original and new acrylic itself?

The original portlight acrylic thickness was 8.5mm. I don’t recall the thickness of the two Lewmar replacement portlights that I bought at an overall cost close to £200 each, and cannot confirm from memory whether they were any thicker than the original portlights. The difference between the original portlights and the Lewmar replacements was noticeable across the dimension of the combined portlight and hinge measurement which had increased from 27mm to 29mm. This was partly due to Lewmar changing the hinge pin thickness from 4mm to 5mm and then increasing the size of the hinge to accommodate the thicker hinge pin.
In your first photo, which I have borrowed for the purpose of this explanation and part of which is shown below, and of which the hinge bracket and it’s securing screw I have marked with a yellow arrow. Well it was these brackets that Lewmar had lengthened to accommodate the increased dimensions of the new hinges and new catches, and it was the securing screw on each bracket and also covered by the yellow arrow, that were so difficult to undo. With you’re boat on a fresh water lake, it is possible that the screws and portlight aluminium frames may not be as badly affected by corrosion as are those boats kept in a salt water environment.

The replacement acrylics that I purchased from a plastics firm were about one millimetre thicker than that originally supplied by Lewmar, but the acrylic thickness is not critical if the area where the hinges and catches fit has been machined out to ensure that the overall measurement between the outer side of the acrylic to the innermost point on the hinge or catch is maintained at 27mm.

In regard to the blinds or covers you have made, I’m sure that anything you do to protect the acrylic from UV light from the sun will help to some extent to prevent any further crazing of the acrylic.
In particular I like the covers you have made for the companionway hatch and door, as much as anything I’m sure that in cold weather it would help to retain some of the heat from your heater within the cabin rather than allowing it to go out and contribute towards global warming no matter how small that contribution may amount to.
Title: Re: Crazed Portlights and Hatches
Post by: ancanc on October 23 2019, 17:27
Hi Salty,
i measured today my acrylic (the original one), it is exactly 8mm thick. That is funny, i tought Lewmar was using some special-sized acrylic to make it (almost) impossile to change the portlights with non-original ones. But (at least on my boat) they are made of 8mm acrylic.
In your DIY-guide you wrote, that the newly made acrylic had a different thickness than the original one. This part i could not really follow, how did you make the acrylic thinner underneath the glued parts? The surface still has to be flat... Or was the newly manufactured acrylic thinner and you had to make it thicker?
Regards:
Andras
Title: Re: Crazed Portlights and Hatches
Post by: Clivert on October 23 2019, 17:45
We put hatch covers on every time we leave the boat.
Makes a big difference over time
Title: Re: Crazed Portlights and Hatches
Post by: Salty on October 23 2019, 20:19
Hi Salty,
.
.
In your DIY-guide you wrote, that the newly made acrylic had a different thickness than the original one. This part i could not really follow, how did you make the acrylic thinner underneath the glued parts? The surface still has to be flat... Or was the newly manufactured acrylic thinner and you had to make it thicker?
Regards:
Andras

Hi Andras,

Hopefully the following photos should show the situation regarding the thickness of the acrylic sheet in way of where the hinges or catches are attached to the acrylic.

The first picture shows an area recessed into the acrylic sheet to ensure that the overal dimension from the outside of the portlight to the innermost point on either the hinges or the catches amounts to as near as possible to 27mm(Note, this is as supplied by Lewmar, but is not normally visible, until in my case after the hinges or catches were removed). The thickness of the acrylic in this recessed area is critical to ensure that after glueing the replaced hinges, that your 27mm limit is maintained. How much acrylic is machined out to form that recess will depend entirely upon the thickness of the acrylic that your supplier has in stock or can buy in on the one hand, and upon how generously you apply the adhesive on the other. The adhesive I have suggested, Methacrylate MA300 does not require lots of it to be applied, so keep it thin.

The second picture shows the under side of a hinge, and the catches are more or less identical in appearance. Note that the hinges and catches have a perimeter moulding which will engage with the horns on the upper and lower edges of the portlight, and this helps to ensure that they fit into the exact right places on the replacement portlight acrylic.

The third picture below shows a hinge in process of being fitted,
 
And the fourth picture shows the same hinge fully pushed into position within the recessed area.

Note, so long as the thickness of the recessed area is calculated properly so that your 27mm measurement referred to earlier is maintained, the overall thickness of the acrylic sheet in use is to a large extent irrelevant because there is nothing that bears directly against the inner surface of each portlight. The recessed areas were cut out by the supplier of the acrylic portlight replacements using their computer controlled machinery to make exactly matching recesses to that shown in the first photo below

I hope the foregoing has provided you with the answers to your questions.

Title: Re: Crazed Portlights and Hatches
Post by: ancanc on October 23 2019, 23:21
Hi Salty,
and thanks for the clarification! I see now, this is not an easy task to manufacture the new acrylics... The recessed areas are not visible while the plastic parts are in place, i thought the acrylics are simply flat.
I am going to use the current portlights until i gather up some courage and start replacing them....
Thanks again,
Regards:
Andras
Title: Re: Crazed Portlights and Hatches
Post by: Salty on October 24 2019, 02:35
Yes, that’s the thing, it takes a bit of courage to start taking them apart knowing that if you make a mistake, that it will cost you quite a lot of money.

I was fortunate in a way because someone, who had their boat ashore over winter in the boatyard where mine also spends the winter months, had replaced a whole deck hatch with a new one and had discarded the original complete with its entire aluminium frame. The normally transparent acrylic within the opening frame was badly crazed, but I saw this as something that I could use to practice dismantling before having a go at the hatches on my own boat. Taking the old discarded hatch apart proved reasonably easy, and that gave me the confidence to look at changing my own deck hatches.

In regard to the portlights, I purchased two new sets of brand new Lewmar portlight lenses, only to discover they would not fit my existing portlight frames because of the changes Lewmar had made to the hinge arrangements. I had to go back to the supplier and buy a set of brackets and hinge bolts etc., in order to fit the new lenses. Removing the original brackets was difficult, but I was lucky, and despite the difficulties I was able to remove each of the securing screws for the brackets on the two forward portlights within the main cabin. But I was deeply disappointed when trying to tackle the remaining four large portlights on my boat, because the securing screws, like the one marked with an arrow in an earlier reply to you, were not going to come out easily.

Being able to replace the two forward portlights in the main cabin left me with two old but intact and thoroughly crazed portlight lenses that I could have a go at trying to dismantle and remove the plastic hinges and catches. After a couple of mistakes I found that I could remove those plastic parts and then began looking at how to stick them back on and also where to get the acrylic lenses made up locally. I was lucky on both counts in that I found a compatible and superbly strong adhesive, and a plastics manufacturer with the right kind of machinery to be able to accurately cut out new lenses Including machining out those recessed areas. The rest, as they say, is now history !!

Also, although I now have two slightly tinted original Lewmar replacement portlights and two non tinted locally made portlights within the main cabin on my boat, up to now no one visiting my boat has spotted the difference. Indeed, in all honesty and despite that I know there is a difference, I’m hard pushed to notice it myself.
Title: Re: Crazed Portlights and Hatches
Post by: IslandAlchemy on October 29 2019, 09:18
I've decided that I'm going to get new acrylics made and have them fixed, as I never open them anyway, so I shall just glue them in.
Title: Re: Crazed Portlights and Hatches
Post by: Salty on October 30 2019, 05:33
For those of you that read through my original postings on this subject, you may remember that I mentioned in regard to covering the acrylics with plastic film to prevent possible UV damage from sunlight, and that the window tinting firm had initially advised that acrylic gave off tiny quantities of gas which until then the ordinary films could not cope with. Well today I read an article posted on the BBC News App about some research carried out by Dr Sarah Jeanne Royer. In her research it seems that most, if not all plastics give off methane and other ozone depleting gasses.

In her article the following statement was found
“What's causing these emissions?
In short it's the Sun. Solar radiation acts on the surface of plastic waste. As it breaks down, it becomes cracked and pitted, these defects increase the surface area of plastic available.”

At the time she was only looking into what was happening with waste plastics, but my contention is that it must be happening to all plastics, and starting from the moment of manufacture.

Perhaps we should start to insist on Portlights and Hatches being made from suitably toughened glass which won’t craze and won’t give off ozone depleting gasses, but then isn’t the whole boat hull made from plastic?  🤢

Having said all that Salty, from the posts here the Gebo hatches are not crazing to any significant degree while the Lewmar ones appear to be frosted after only a few years.  That points to a variable in the materials used by the two companies.  No need for glass, just Gebo acrylic.  My hatches ar 18 years old and have little crazing.

My point in the posting above about using glass, was in regard to global warming due to the emissions being given off plastics.

In regard to the quality of the acrylic being used, I whole heartedly agree, a friend has a Dufour 41 slightly older than my boat and his acrylics are in excellent condition. But in regard to using Gebo acrylics instead of Lewmar, unfortunately it’s not much help if the sizes and fittings are different which I suspect they are. If your boat is already fitted with Gebo then it’s great as you probably won’t ever have to change them, but the Lewmar stuff being produced in the early 2000s was crap. Indeed a neighbour purchasing a brand new  Beneteau at that time had all his acrylics replaced under warranty because of almost instant crazing.
Title: Re: Crazed Portlights and Hatches
Post by: Jeffatoms on February 09 2020, 17:55
Thanks to all for this very thoughtful thread.  This is also on our list, maybe in 2020 after the saildrive fiasco is resolved.

I've searched without success for Gebo replacement lenses or even entirely new portlights with no success.  My new plan is to cash in on my "mate rate" to have both tempered glass and acrylic lenses cut on a water jet table.  I'll need to extract on the get a *.dfw file.

Can anyone tell me the thickness of the Gebo portlight lenses on a Bav 38 Ocean.  A bonus would be if someone has an accurate electronic drawing of the portlights in question... I know that's a lot but I am an optimist.

Thanks in advance!
Jeff
SV Zephyrus
Title: Re: Crazed Portlights and Hatches
Post by: Salty on November 04 2020, 05:35
Having an electronic drawing of the Portlight or Hatch lense that you want to replace would be helpful, but I dont have either the facility or the know how to produce such a drawing. So where it came to getting a replacement lense made at my local acrylic sign maker or workshop, I took them an original for them to copy. This meant taking a hatch or portlight from my boat to their workshop and basically saying to them “Please Sir, can you make me another one of these?”  That however left me with a problem of what to do with the open hole in my boat where the hatch or portlight, now being used as a template, had come from. So I cut a piece of thick plywood to use as a temporary cover. This cover was placed over the outside of the hatch or portlight from where the lense had been removed, and was secured in place using a long bolt or two through the plywood, through the now open hatch or portlight and through a thick piece of wood placed on the inside of the hatch or portlight. The bolt was then tightened and fitted with a second nut tightened up against the first to make things more difficult for any light fingered soul who might wish enter the boat while I was away. Lastly the area was covered with a heavy plastic sheet that was secured in place to keep out any rain.  This was done while my boat was onshore over the winter months, so Mr Lightfingers also had a problem of how to get onboard because the ladder I used was carefully laid out under the boat where it was chained and padlocked to the boat cradle supports.
Title: Re: Crazed Portlights and Hatches
Post by: IslandAlchemy on November 04 2020, 07:37
If you happy not to have opening windows, I have 4 lenses left from when I had a load made up to replace the lenses in my windows.

They are 10mm thick and I am selling them for £160 (for all 4) including all the fixings you need and some fitting instructions that I put together.

This will save you a small fortune over buying Lewmar replacements.
Title: Re: Crazed Portlights and Hatches
Post by: aquapore on January 25 2021, 05:54
Replacement of crazed port lights

IslandAlchemy suggested need to electronic drawing of portlight for manufacture new ones.

I am happy to supply such a drawing with a file that can be used by a plastics jobbing shop with 3D NC router to manufacture new ones.

All I need is a photo copy of an original plastic 1:1 scale for outline an the depths of any rebates. Attach photo copy as PDF with scale 100%.

Regards

Robert Wechsler
Aquapore
Title: Re: Crazed Portlights and Hatches
Post by: IslandAlchemy on January 25 2021, 09:34
Replacement of crazed port lights

IslandAlchemy suggested need to electronic drawing of portlight for manufacture new ones.

I am happy to supply such a drawing with a file that can be used by a plastics jobbing shop with 3D NC router to manufacture new ones.

All I need is a photo copy of an original plastic 1:1 scale for outline an the depths of any rebates. Attach photo copy as PDF with scale 100%.

Regards

Robert Wechsler
Aquapore

It's all done.  I took measurements and designed a fixed replacement and then had a load of them made (I had to buy a whole sheet of acrylic, so has 24 lenses made out of it).  I got them made from 10mm thick actylic, so they are thicker than the originals.

I have replaced all my windows and have supplied the spare ones to 3 other boat owners, who have also now replaced their windows (one being Salty Lass, if you look them up on YouTube, they did a video on it last month).

The lenses cost just under £40 each including all the screws and caps, so less than 1/4 of the price of the Lewmar replacements.

If others are interested in having some, I can get another sheet cut, but would need enough buyers to get to 24 units.

Attached are a couple of photos of the new windows fitted.

If anyone is interested, PM me.
Title: Re: Crazed Portlights and Hatches
Post by: Salty on January 25 2021, 13:56
Well done Island Alchemy, this just shows what can be done if boat owners have a mind to do a job where the original suppliers want to hold us all to ransom.
Title: Re: Crazed Portlights and Hatches
Post by: IslandAlchemy on February 01 2021, 11:01
I have had someone ask me if I can get any more of these.  I have explained that I would have to get another whole sheet done (24 windows), so would need a few people wanting them to make it viable.

If anyone out there is interested, let me know, and if we can get enough units required together, I am happy to get another sheet cut and supply the kits to others.
Title: Re: Crazed Portlights and Hatches
Post by: jakobmagnusson on April 06 2022, 07:32
Hi Salty and all other Bavaria-friends!
Inspired by the method originally posted by Salty I made 9 new portlight lenses for my Beneteau Oceanis 411. What I thought was the hardest things to figure out was the removal of the fittings and what glue to use, and here I found the answers! And other great tips.  THANK YOU!

I made a film of my project, which also included the routing of the lenses, I hope that can add some inspiration on doing this on your own:
https://youtu.be/U9taRDfnJIY

Regards,
Jakob
Title: Re: Crazed Portlights and Hatches
Post by: Odysseus on April 06 2022, 10:13
Well done, brilliant job, just shows how bad lewmar are for not owning their responsibility for poor product they put in the market, the answer is dont  buy Lewmar products.

Well done again.

Odysseus
Bav 38
Title: Re: Crazed Portlights and Hatches
Post by: p_schurli on April 08 2022, 11:18
Hello Bavaria Owners!
I warm up this thread because all my portlights and hatches are badly crazed and I want to change them. I have a Bavaria 40 from 2002 with Lewmar portlights and hatches. Outline measurement is 690x188mm for the portlights and 556x556 / 556x276 for the hatches. If anyone could give my old acrylics (any condition) as samples for reproduction I would be very grateful :). Or maybe someone can provide CAD files in any format. I could give these files to a local company for reproduction. My boat lies in Greece and I live in Austria, so I cannot use my own as samples.
Regards, Peter
Title: Re: Crazed Portlights and Hatches
Post by: Ailatan on April 09 2022, 23:46
I am glad that this thread has been refloated because I want to thank Salty for showing us the way to solve this problem that was driving me mad.
He also answered my doubts that I sent him through p.m.
All in all it has been a very very hard job because my B 44 has 8 long portholes, 4 small portholes, 3 big hatches an 4 small hatches and all of them were crazed. If I had bought all that in SVB I would have got the title of "client of the year".
Unfortunately the local company that cut the acrilyc doesn't want to give me the drawings.
After fixing the acrilycs I made the covers to try to delay the process as much as possible. I will put some pictures
Title: Re: Crazed Portlights and Hatches
Post by: p_schurli on April 11 2022, 15:49
Great job Ailatan!
You have got tinted glass which is great in sunny Greece!
Is there a possibility that I place a order at your local company? This would be really great. Or do you have some of your old acrylics with I could use as samples?
I have changed the rubber sealing of my two big hatches. On the first hatch it was very hard to separate the aluminium frame. On the second one it was easy because I sprayed MOS2 onto the connectors and let it work for some days.
Kind regards, Peter
Title: Re: Crazed Portlights and Hatches
Post by: Ailatan on April 12 2022, 15:11
Hi Peter, I sent you a p.m.
Title: Re: Crazed Portlights and Hatches
Post by: Salty on May 04 2022, 08:01
Hi Salty and all other Bavaria-friends!
….I made 9 new portlight lenses for my Beneteau Oceanis 411. What I thought was the hardest things to figure out was the removal of the fittings and what glue to use, and here I found the answers! And other great tips.  THANK YOU!

I made a film of my project, which also included the routing of the lenses, I hope that can add some inspiration on doing this on your own:
https://youtu.be/U9taRDfnJIY

Regards,
Jakob

Well done Jakob, and thank you for your kind words.

I think you have taken this project of replacing old and crazed portlights to a whole new level with your excellent video and very clear and step by step explanation.

I have a router tool, but lack the confidence to use it and hence why I went to a local sign maker, but your video will provide inspiration for others.

Unfortunately due to health reasons I have sold my boat and only occasionally look back at this website to see how others are coping with the complexities of boat ownership.

Again, well done Jakob, and well done to those others that have also taken up the challenge to change their portlights and hatches on their boats, and without the need to empty their bank accounts in the process !!

Kind regards
Salty.
Title: Re: Crazed Portlights and Hatches
Post by: p_schurli on May 25 2022, 20:52
Hi Salty and all other Bavaria-friends!
Inspired by the method originally posted by Salty I made 9 new portlight lenses for my Beneteau Oceanis 411. What I thought was the hardest things to figure out was the removal of the fittings and what glue to use, and here I found the answers! And other great tips.  THANK YOU!

I made a film of my project, which also included the routing of the lenses, I hope that can add some inspiration on doing this on your own:
https://youtu.be/U9taRDfnJIY

Regards,
Jakob

Congratulations Jakob!
I am sure this is the best boat refit video I have ever seen on youtube. You have a new subscriber!
Regards, Peter
Title: Re: Crazed Portlights and Hatches
Post by: jakobmagnusson on August 31 2022, 06:34
Quote
Well done Jakob, and thank you for your kind words.

I think you have taken this project of replacing old and crazed portlights to a whole new level with your excellent video and very clear and step by step explanation.

I have a router tool, but lack the confidence to use it and hence why I went to a local sign maker, but your video will provide inspiration for others.

Unfortunately due to health reasons I have sold my boat and only occasionally look back at this website to see how others are coping with the complexities of boat ownership.

Again, well done Jakob, and well done to those others that have also taken up the challenge to change their portlights and hatches on their boats, and without the need to empty their bank accounts in the process !!

Kind regards
Salty.
Thank you. And all the best.
/Jakob
Title: Re: Crazed Portlights and Hatches
Post by: ancanc on September 12 2023, 12:20
Hi Jakob,

a fantastic video - unfortunately I do not have the equipment to make the acrylic myself....
You made it clear that it is very important to keep the thickness of the acrylic plus the handle to be 27mm. I was thinking that all the handles have the same size - it would also mean that the thickness of the acrylic must also be the same for all recesses? Did you measure the thickness of the recessed acrilyc by chance?  If I find a company which is willing to cut my acrylic - I cannot tell them to measure the size with a handle, I can only say them that the recessed area should have a thickness of 7mm - or so.

I have tried to order one from a local company - unfortunately it went wrong, they did not have the proper machinery for this task.
Is there anyone who ordered such an acrylic with success?
To be honest I do not really understand why no one is  offering such acrylics (without the hinges and handles) yet, I am sure they could sell a lot of theese...  From SVB/Lewmar it would cost me now EUR 300 plus EUR 57 for the replacement set. And this 8 times. Plus 4 times the small ones á EUR 220.

Has anyone managed to break a handle / hinge while taking it off from the old acrylic? I assume it is not easy to find one of theese...

I am a bit confused about the acrylic itself too. There are two types of acrylic glas:

Acrylic glass cast (Acrylglas gegossen or GS)

Acrylic glass extruded (Acrylglas extrudiert or XS)

What type is better to be used as a boat windows?


Thanks,
Regards:
Andras

Hi Salty and all other Bavaria-friends!
Inspired by the method originally posted by Salty I made 9 new portlight lenses for my Beneteau Oceanis 411. What I thought was the hardest things to figure out was the removal of the fittings and what glue to use, and here I found the answers! And other great tips.  THANK YOU!

I made a film of my project, which also included the routing of the lenses, I hope that can add some inspiration on doing this on your own:
https://youtu.be/U9taRDfnJIY

Regards,
Jakob
Title: Re: Crazed Portlights and Hatches
Post by: symphony2 on September 12 2023, 12:45
I don't think 7mm is a standard size in either acrylic or polycarbonate. 6 or 8mm are standard. For local supply look for firms that make signs or shop fittings. In the UK there are many firms that deal on line and will machine (cut to size, polish drill holes) to your drawing or pattern. Pretty sure there will be similar in Hungary. Suggest you take one of each size out of the frames to use as patterns.

The reason why nobody offers them of the shelf is because it is normally easy to get them made as described.
Title: Re: Crazed Portlights and Hatches
Post by: ancanc on September 12 2023, 16:01
Thanks, I might have put it wrong... The acrylic itself is an 8mm acrylic, I meant the recessed area underneath the hinges and handles. I was told that the cast acrylic might have an almost 10% tolerance in the thickness and it is the ground why they are recessing the acrylic to a specified size: 27mm with the hinge glued on... But if you deduct the hinge it must be the same for all recessed areas, I think. The 7 mm was only a guess...

You wrote: "The reason why nobody offers them of the shelf is because it is normally easy to get them made as described." I find several firms offering porthole acrylics for the old style Lewmar portholes and hatches. They are also easy to make,  there must be something else too, don't you think?

Regards:
Andras
Title: Re: Crazed Portlights and Hatches
Post by: ancanc on September 15 2023, 12:29
Is there anyone here, who bought a new acrylic from Lewmar with the assembly kit (4mm -> 5mm)? If the old acrylic (for 4mm holes) is not needed anymore  I would happily buy them - for testing purposes and for the spare hinges/fittings, should I break one during the disassembly...
Thanks
Title: Re: Crazed Portlights and Hatches
Post by: Ailatan on September 15 2023, 22:39
I have done that job and I have a local supplier. I'll send you a p.m.
Title: Re: Crazed Portlights and Hatches
Post by: Jeffatoms on September 17 2023, 01:22
We too have this problem with our Gebo hatches and portlights on our Ocean 38 from 1998.   Recently I corresponded with Gebo and they said the only solution to fixing the portlights was full replacement.  My guess is that to replace the portlights alone, parts would exceed $2,000 USD.  My wife suggested we save the $2,000 and call them "privacy" windows.  She's the Captain.  I'm fine with that.
Title: Re: Crazed Portlights and Hatches
Post by: Yngmar on September 17 2023, 08:49
The Gebo panes are much easier to replace than the Lewmar, as they don't have any funky glue or recesses. You can easily cut them yourself from sheet material.
Title: Re: Crazed Portlights and Hatches
Post by: ancanc on September 17 2023, 18:53
Thanks, on my earlier Bavaria 34 I had Gebo portlights, they did not need to be replaced... I still see my old Bavaria 34  (1999), she is lying in the same marina and the portlight are still OK.