Compression post too short? Rebuild of door frame

[Sweetness]

This is the latest update. The original post below.

We've been swayed by an argument that fixing the door frame might be a simpler solution than making the compression post taller. So, I've used a clamp bar to crack the frame. The frame is made of 4 pieces of mahogany (I guess..). Of course they are glued together with epoxy, so when you stretch the frame with clamp, they have to crack. The cracks luckily occurred near the original seams, so we've been able to put everything back together with epoxy in a way that it is impossible to notice anything without specifically looking.

There is a layer of some sort of silicone rubber between the bulkhead and the frame bits which I presume has two functions: prevents the frame from making noises when the boat is rocked, and pushes the frame in, so that the parts stay together. Although the original looked fine, we've cleaned it all up and replaced with stretches of CT1. I've also sanded the bottom of the bulkhead opening down and padded it with CT1 so that both sides are equal. I did not sand both down to the same level in case the bulkhead readjusts when the mast is removed. Before reassembling the frame I've sprayed the bulkhead with teflon lubricant in hope to reduce creaking noises.

The shrouds are now under 1000 kg tension one each side, and the door is fully functional with about 5 mm gap where previously there was none.

See pictures.



>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>Original post:

On our Bavaria 34 (year 2000) the fore cabin bulkhead appears to be distorted by the mast pressure to the point that the door frame prevents the door from being closed when the shrouds are tensioned to about 1000kg. I don't like the idea of sailing with insufficiently tensioned rig, so I've been experimenting with jacking up the deck with a bottle jack (the mast foot for some reason is not centered at the compression post). It looks like with sufficient pressure applied, the deck has the capacity to move up, relieving the pressure from the bulkhead. The movement of the bottle jack required to unjam the door had to be at least 2 cm.

Questions:
1. Does that indicate that the compression post on the boat is insufficiently long and can be padded to solve the problem?
2. Has anybody had the experience of removing/replacing the mast compression post on Bavaria(34)? How is it attached at the bottom? Is it attached to the bulkhead? When jack removed pressure from the post, it seemed that the post lifted by a few mills off the hull liner at the bottom and it seemed that there was some sort of compressed rubber (or cured silkaflex) underneath.

[Yngmar]

The compression post was not too short when the boat was built, they're all from the same highly computerized factory and no first owner would've accepted a new boat where the forward cabin door is jammed. So it's safe to assume that something has since changed shape.

Possible candidates are either the deck being compressed or the hull matrix that the compression post is resting on is coming apart.

The deck is generally foam cored in most areas, although I'm not sure about the area under the mast foot - hopefully it isn't, but if it is the core may be compressed. Oddly enough the core is exactly 20mm thick, at least on my boat (which is the same generation and built the same way). This would be relatively easy to diagnose (pull one of the bolts of the mast step or drill a hole and have a look) and repair, although the mast has to come off for fixing it.

The bottom of the compression post rests on a stringer that is part of the hull grid that also provides the strength for the keel. If that has become delaminated, it may be sagging downwards. This would be extremely difficult and costly to repair, and it would be very risky to go sail like that.

Either way you need to find out what has caused the boat to change shape. Padding the compression post would be just fixing the symptoms and ignoring the underlying cause, which could be very dangerous.

Hopefully it's just a compressed deck under the mast step!

[Ricd]

I have had the same problem for last 10 years so no panic on my 34 2000 build, owners version.  I also have heard its a common issue on the 34 2000.  Door jams/becomes stiff when rig is under tension on a beat and releases when tension is loosened ..  I had new standing rigging last year and spoke with rigger about it.  He quoted many boat types where bulkhead doors jam when rig is under load.  He came back a couple of months ago to re-tune rig after it had all settled and once re-tuned the door stopped jamming.It may return, I am not particularly worried by it.

[Salty]

On our Bavaria 34 (year 2000) the fore cabin bulkhead appears to be distorted by the mast pressure to the point that the door frame prevents the door from being closed when the shrouds are tensioned to about 1000kg. I don't like the idea of sailing with insufficiently tensioned rig, so I've been experimenting with jacking up the deck with a bottle jack (the mast foot for some reason is not centered at the compression post). It looks like with sufficient pressure applied, the deck has the capacity to move up, relieving the pressure from the bulkhead. The movement of the bottle jack required to unjam the door had to be at least 2 cm.

Questions:
1. Does that indicate that the compression post on the boat is insufficiently long and can be padded to solve the problem?
2. Has anybody had the experience of removing/replacing the mast compression post on Bavaria(34)? How is it attached at the bottom? Is it attached to the bulkhead? When jack removed pressure from the post, it seemed that the post lifted by a few mills off the hull liner at the bottom and it seemed that there was some sort of compressed rubber (or cured silkaflex) underneath.

Roman.

With respect to all, it seems to me that the root of the problem lays in the tension on the rigging. Assuming that each of the shrouds is tensioned to 1000kg as mentioned above, and considering that you have two mains, plus two lowers, plus the tension in the forestay and that in the back stay, plus the weight of the mast and boom and this all adds up to a hell of a lot of force acting downwards on that compression post. With 1000kg in each wire that adds up to six tonnes plus, and all being concentrated on and supported by the cabin top and compression post !!

Have you checked whether the compression post is bending under the load it currently has to support?
Have you tried reducing the tension on the shrouds, including both the forestay and the backstay to see whether that makes the difference needed to allow your cabin door to shut?
When you use your bottle jack, does the cabin top in way of the foot of the mast change shape?
In regard to the rig tension, ask yourself if the tension on it was increased by something you did since you acquired the boat, and has the problem with the door not closing manifested itself since, or not too long after the date of that adjustment.

[Clivert]

We have a 2001 34 and this problem only occured when the rig was overtightened.
Had no problem with performance with slightly less rig tension.

[Sweetness]

The compression post was not too short when the boat was built, they're all from the same highly computerized factory and no first owner would've accepted a new boat where the forward cabin door is jammed. So it's safe to assume that something has since changed shape.

Possible candidates are either the deck being compressed or the hull matrix that the compression post is resting on is coming apart.

The deck is generally foam cored in most areas, although I'm not sure about the area under the mast foot - hopefully it isn't, but if it is the core may be compressed. Oddly enough the core is exactly 20mm thick, at least on my boat (which is the same generation and built the same way). This would be relatively easy to diagnose (pull one of the bolts of the mast step or drill a hole and have a look) and repair, although the mast has to come off for fixing it.

The bottom of the compression post rests on a stringer that is part of the hull grid that also provides the strength for the keel. If that has become delaminated, it may be sagging downwards. This would be extremely difficult and costly to repair, and it would be very risky to go sail like that.

Either way you need to find out what has caused the boat to change shape. Padding the compression post would be just fixing the symptoms and ignoring the underlying cause, which could be very dangerous.

Hopefully it's just a compressed deck under the mast step!

There is no foam under mast step. Only about 5mm of glass with what seems a fairly thin metal plate (gues 2-3m) laminated into another 5mm just under the step. Then about 7mm metal plate (aluminium?). Then the post. The headliner has a removable panel, so it is all clearly visible there.

The post sits on the hull liner. Liner seems intact. The hull liner transverse beams are hollow inside except for the part under the compression post. That bit looks solid by the sound produced when you tap on it.

I do agree that the boat hull might have changed shape since it came from the factory. However, by the way the door is mounted, it looks like the frame was already slightly distorted at the factory (so, a build defect), but the tension on the rig was just enough for the door not to jam.

[Sweetness]

I have had the same problem for last 10 years so no panic on my 34 2000 build, owners version.  I also have heard its a common issue on the 34 2000.  Door jams/becomes stiff when rig is under tension on a beat and releases when tension is loosened ..  I had new standing rigging last year and spoke with rigger about it.  He quoted many boat types where bulkhead doors jam when rig is under load.  He came back a couple of months ago to re-tune rig after it had all settled and once re-tuned the door stopped jamming.It may return, I am not particularly worried by it.

I'm not panicking (yet) , But the future buyers might...
Would you be able to measure and post the shroud tension? Thank you.

[Ricd]

We have a 2001 34 and this problem only occured when the rig was overtightened.
Had no problem with performance with slightly less rig tension.

As I mentioned when the rig was renewed last year and then re-tuned once settled, the door no longer jams so can only assume it was previous over-tensioned.

[Sweetness]

With respect to all, it seems to me that the root of the problem lays in the tension on the rigging. Assuming that each of the shrouds is tensioned to 1000kg as mentioned above, and considering that you have two mains, plus two lowers, plus the tension in the forestay and that in the back stay, plus the weight of the mast and boom and this all adds up to a hell of a lot of force acting downwards on that compression post. With 1000kg in each wire that adds up to six tonnes plus, and all being concentrated on and supported by the cabin top and compression post !!

Have you checked whether the compression post is bending under the load it currently has to support?
Have you tried reducing the tension on the shrouds, including both the forestay and the backstay to see whether that makes the difference needed to allow your cabin door to shut?
When you use your bottle jack, does the cabin top in way of the foot of the mast change shape?
In regard to the rig tension, ask yourself if the tension on it was increased by something you did since you acquired the boat, and has the problem with the door not closing manifested itself since, or not too long after the date of that adjustment.

The post seems solid (~10x15cm cross section). Reducing shroud tension definitely makes the difference. However this means I need to drop tension to 600kg which is way below 20% selden recommended tension for 8mm wire. This is with backstay completely lax (swept back spreaders).

The cabin top does not change visibly but the mast step sits on the section of the deck with what seems a metal plate laminated in. So, any distortion will unlikely to be local.

When we bought the boat the door worked fine, but we did change the rig (by professional) and that's when we noticed the door is very difficult to close/open. Afterwards I've been fiddling with rig (because of the door problem). In the end I've decided to tension to selden specs, which is probably higher than what the riggers originally did. The previous owner also agreed that the door frame was distorted since as long as they remember. They bought her from the original owner.

[Sweetness]

We have a 2001 34 and this problem only occured when the rig was overtightened.
Had no problem with performance with slightly less rig tension.

Would you be able to measure and post the shroud tension? Thank you.

[Baddox]

I'm in the process of replacing our Bav 30 Cruiser's standing rigging.  The wire is 7mm and has a breaking strain of either 3500 to 4000kg depending on the wire type.  Being a fractional rig with swept spreaders, the stays need to be tensioned to 20% of their breaking strain, so 700 to 800kg.
Unless your stays are thicker than 7mm, they appear to be over-tensioned.

[Sweetness]

I've measured several times with caliper and it is always 8. I don't think the ovensioning is the case. Also, the tension gauge from spinlock for some reason thinks the wire is tad thinner. So, I believe I'm actually under 1k.

[MarkTheBike]

We have a 2001 34 and this problem only occured when the rig was overtightened.
Had no problem with performance with slightly less rig tension.

B34/2001 - I had the rigging replaced last year (no damage, just age). Everything was fine before but the young lad who tightened it up by eye said, "Nah, don't use strain gauges, just do it by feel". Sure enough, massively overtightened, door jammed shut then unclosable once freed. Their first comment was ..."take it out in a 6-7 and ear'ole it a bit. That'll stretch it...". I did, in a 7-8 but no change. Eventually the guv'ner turned up and loosed it off a bit. His face told me what I already knew. The shrouds are just right now, good and solid to windward and almost but not quite soft to leeward. Nothing sticks, nothing's stressed (including me) and she sails a treat.

[Clivert]

The 34 has a strong rig and the easy way to solve your problem is to easy the shrouds half a turn each until the door is ok, then lock off.
An overtensioned backstay can also cause the same problem.
No need to get too technical or precise.
If not get a recommended rigger to check.
Where are you moored ?

[Sweetness]

The 34 has a strong rig and the easy way to solve your problem is to easy the shrouds half a turn each until the door is ok, then lock off.
An overtensioned backstay can also cause the same problem.
No need to get too technical or precise.
If not get a recommended rigger to check.
Where are you moored ?

Half a turn does not cut it. It needs to be substantially lower than the spec. The riggers suggested to trim the door. I'm looking for an alternative solution. East coast.

[JEN-et-ROSS]

When we bought our current B38 about 12 years ago, we noticed the door frame in the forward bulkhead leading to the forecabin was slightly 'squint'. The door didn't jam but having decided to go to survey we ensured that the surveyor was well aware of our concerns.
 
On the day of the survey he turned up well prepared and spent considerable time on the bulkhead/compression post area.
During the inspection we stripped away the mahogany cladding around the C/post and dropped the headlining to expose the deckhead. The foot of the C/post was also examined closely and measurements taken and compared. (We had agreed with the owner to put it all back together again whether we bought the boat or not)

The conclusion?....It was built that way and had always been like that. In the 12 years we have owned the yacht nothing has changed.
 Your situation may be different, but boats, all boats, even factory built boats are 'one offs', could the way your boat was built be part of the problem?......Bill

[Sweetness]

When we bought our current B38 about 12 years ago, we noticed the door frame in the forward bulkhead leading to the forecabin was slightly 'squint'. The door didn't jam but having decided to go to survey we ensured that the surveyor was well aware of our concerns.
 
On the day of the survey he turned up well prepared and spent considerable time on the bulkhead/compression post area.
During the inspection we stripped away the mahogany cladding around the C/post and dropped the headlining to expose the deckhead. The foot of the C/post was also examined closely and measurements taken and compared. (We had agreed with the owner to put it all back together again whether we bought the boat or not)

The conclusion?....It was built that way and had always been like that. In the 12 years we have owned the yacht nothing has changed.
 Your situation may be different, but boats, all boats, even factory built boats are 'one offs', could the way your boat was built be part of the problem?......Bill

I agree that it is a build defect. I also believe it is not structurally dangerous. Now there is a number ow ways we can go from here :
a) Sail with lax shrouds. Did that for a year, not comfortable with the idea.
b) Ignore the issue. Tensioned shrouds to spec and kept door open for some time. Not that it is a big deal, but you keep being contact being reminded whenever you decide to close it. Very annoying.   
c) Grind the corner of the door and pretend problem solved. This solution does no appeal to me since it is irreversible. It will also keep the pressure on the bulkhead which might result in unwanted sounds at choppy anchorages.
d) Do something major.

I am trying to assess the options and challenges for (d).

By any chance, do you know if post is glued, screwed, etc to the bulkhead or any other part of the boat?

[Symphony]

I think you will find you can take the frame out and reshape the bulkhead where the frame sits. The distortion when you tighten the shrouds is acting on the bulkhead which in turn distorts the frame so the door won't fit it. The frame is designed to float in the bulkhead to cater for movement. Expect you will find the frame is tight in the top right hand corner looking from the saloon as this is where the pressure is from the mast because the door is offset. Interestingly the later Farr designed boats don't have this problem as the mast is further aft with its own compression post so there is no pressure on the bulkhead and the door is central.

BTW this problem is not unique to Bavarias - ask any owner of a Sadler 32 or a Sigma, for example. It only takes a very small movement of the deck moulding to move the bulkhead, particularly as it is not fully bonded to the hull or deck.

[Sweetness]

I think you will find you can take the frame out and reshape the bulkhead where the frame sits. The distortion when you tighten the shrouds is acting on the bulkhead which in turn distorts the frame so the door won't fit it. The frame is designed to float in the bulkhead to cater for movement. Expect you will find the frame is tight in the top right hand corner looking from the saloon as this is where the pressure is from the mast because the door is offset. Interestingly the later Farr designed boats don't have this problem as the mast is further aft with its own compression post so there is no pressure on the bulkhead and the door is central.

BTW this problem is not unique to Bavarias - ask any owner of a Sadler 32 or a Sigma, for example. It only takes a very small movement of the deck moulding to move the bulkhead, particularly as it is not fully bonded to the hull or deck.

I think this is actually a pretty good idea. The frame is made of 4 parts. I should be able to pull the top an bottom out as they are holding the sides in place. However from what I see, there is a bit of clear silicone between frame and bulkhead. Are there any sort of tools designed for dismantling such frames?

[JEN-et-ROSS]

By any chance, do you know if post is glued, screwed, etc to the bulkhead or any other part of the boat?

Our yacht is somewhat older than yours and a little differently put together in that the bulkhead is not floating but rigidly glassed in.
 The compression post is positioned on the saloon side of the bulkhead and is not attached to it in any way, nor does it appear to be fixed top or bottom, but sits in a sort of socket at the deckhead and a similar fitting above the keel, or at least that's how it seemed to me.....Reading these posts I realise this is a more common issue than I imagined.......Bill.

[Escapade]

Also our yacht is older than yours but only for a few years (1997) and compression post is in the saloon side.
As you can see from attached picture also our door frame is slightly distorted, but the joints between the top part of the frame and the side ones are perfect. Hence I assume the frame has been built that way.
Incidentally though our Selden mast instructions indicates standard tension 15 to 20% our rigger has tuned them at 10% and they appear well tensioned, no slackness at all in the leeward shrouds when sailing upwind with 15-20 knots.
Atb
Oliver

[Sweetness]

Also our yacht is older than yours but only for a few years (1997) and compression post is in the saloon side.
As you can see from attached picture also our door frame is slightly distorted, but the joints between the top part of the frame and the side ones are perfect. Hence I assume the frame has been built that way.
Incidentally though our Selden mast instructions indicates standard tension 15 to 20% our rigger has tuned them at 10% and they appear well tensioned, no slackness at all in the leeward shrouds when sailing upwind with 15-20 knots.
Atb
Oliver

Thanks for the pic. Ours is similar except that the door opens inside the cabin and hinges are on the starboard side. I'm going to try to take the frame apart next weekend. Figured that if I push the sides apart with spreader clamp I might have a chance to pull the top and bottom bits out.

[Sweetness]

Status update

Pulled the frame apart by clamp bar. The procedure is somewhat destructive. The pieces are joined together by epoxy. So, the wood splits. The split is quite nice in the sense that I'm hooping to glue it back together with epoxy so that the seam will be nearly invisible.

The frame sits on the bed of silicone. Of course the bedding is thicker on the wrong sides. I.E. just removing the thick silicone allows re-positioning the frame so that the door gets enough clearance.

The bulkhead is made of two parts with the seam going through the middle of the door opening. The larger part, which is being pressed down by the deck at the mast, is visibly recessed into the silicone bedding in the hull. The smaller part seems to experience no pressure. Result - about 5mm difference at the bottom.

I am planing to sand down some of the gap difference. This will allow lowering the starboard side of the frame even further down. Making them even is probably not the best thing to do since when the mast is removed, the whole thing might move back, potentially causing the opposite deformation.

The builders clearly saw there is an issue as they mounted the door hinges to fit the door in the skewed opening.

In case I fail to reassemble the old frame, any suggestions on how to order a new one?

See pictures

[Ricd]

Also our yacht is older than yours but only for a few years (1997) and compression post is in the saloon side.
As you can see from attached picture also our door frame is slightly distorted, but the joints between the top part of the frame and the side ones are perfect. Hence I assume the frame has been built that way.
Incidentally though our Selden mast instructions indicates standard tension 15 to 20% our rigger has tuned them at 10% and they appear well tensioned, no slackness at all in the leeward shrouds when sailing upwind with 15-20 knots.
Atb
Oliver

My door frame is also distorted and has been forever and likewise the seams on the bulkhead wooden sections have never moved hence seems to have been like that since build.
Thanks for the pic. Ours is similar except that the door opens inside the cabin and hinges are on the starboard side. I'm going to try to take the frame apart next weekend. Figured that if I push the sides apart with spreader clamp I might have a chance to pull the top and bottom bits out.

[Duggy]

I realise that I am posting onto a discussion that is now 4 years old and may just be shouting at the sea here, but I am currently considering whether to buy a 1999 Bav 34, 3 cabin version and it is clear to me that this boat has exactly the same issue as what I am seeing so brilliantly described and discussed here (seriously though, how did humanity cope before forums...).

Sweetness - It sounds like you took the approach that you were not prepared to compromise on rig tension and chose instead to make modify the door frame.  How are things looking 4 years on and would you still make the same decision today?

Ultimately, I am keen to get some wisdom from the hive mind on whether to proceed with this sale.  The boat I am looking at had its standing rigging fully replaced earlier this year and now the port-side heads door is tight and the starboard-side door will not close at all (overlap of maybe 5mm).

Any thoughts gratefully received.