Brunton Autoprop HP20 APS Anodes

[Impavidus]

Hi peeps!

Brunton props are great but, they do eat anodes as the design makes the fixing point for the M6 screws the thinnest part of the anode. I have a HP20 APS Anode design that doubles the surface area and zinc content while keeping the fixing bolts buried deep in the anode where they can be sealed in with Sika. This should extend the life considerably.  They are rough cast then finished on my lathe at the moment..........

I can make one or two for myself but, I was wondering if it is worth making a couple of moulds and casting 25-30 or so which would bring the cost down very significantly.

Would there be any interest?

Ant.

[Impavidus]

Photo of the anode I made and fitted.
1. Melted down old anodes in a bean can.
2. Cut bean can away with tin snips.
3. Turned zinc to right dia on lathe and drilled holes with counter bore using rotating table.
4. Milled flats to clear prop on milling machine.

Fitted and working for 2 months now. Twice the surface area and twice the zinc content. NB the fixings are buried in the zinc and closed off with sika. This gives more metal to secure the anode and prevents it falling off before its half used as the OEM ones do.
Hope this helps someone.

Ant 

[s/y Susanne]

I have an alternative to the rather weak design of the Brunton anode which fails exactly as Ant describes.

I asked a machine shop to turn a stainless steel piece to the same forward end dimensions as the Brunton anode but with a 2" tail of 1" round bar projecting sternwards. It bolts onto the prop instead of the anode using the three fixings but I clamp a low cost shaft anode onto the tail and it lasts all year in the Med unlike the original part which was usually missing on lifting.

Sorry I don't have a pic to hand but you get the idea!

Sorry Brunton, great prop, lousy anode.