35 bertram rotten bulkhead

[cuzwecan]

The bulkhead behind the port engine and in front of the fuel tank has some rotten places (the one the shaft runs through) can I cut out just the rotten place and replace with new wood ? What would be the best way to do this ? The worst place is near the stringer. Also I read awhile back rotten wood (stringers and bulhheads ) has no effect on the strength of a '31 is that truth for a '35 ? Thanks Randy

[CaptPatrick]

Randy,

Welcome Aboard!

The bulkhead in question is not a structural member, so you're not loosing strength or integrity. Replacing all or part of with plywood is OK so long as as you use epoxy to bond all repairs together. A layer of fiberglass over the wood would be recommended, but at least a couple of coats of epoxy to seal out moisture. Use a ply that has exterior glue lamination, but NOT pressure treated. Epoxy will not bond well to PT...

Br,

Patrick

[cuzwecan]

Thanks Capt. I was wondering if the bulkhead is structural. Thanks Randy

[JohnD]

Hi Randy, I've got a B35 also and have water issues in the same bulkhead where the shaft goes through and on my stb side there's a crack above the opening where the motor/trans hit it during a replacement (prior to my stewardship). Anyway, when I do my motors this year I'm going to replace mine and make sure I glass over at least the lower half of the opening where the shaft goes through. Regarding structural aspect of a B35, I think that the bulk of the cabin/flybridge load is on the fg sill and floor structure. The ply bulk head isn't as critical piece of the structural pie.

When comes to marine ply, I don't have much experience but have read a good bit about the different grades and plan to use a merante 1088. If you ever have a chance to comper the ply used by bertram to that of other mfg you can really see the difference in the quality and how it holds up.

Good luck and make sure you check out the building tips on techniques for repairs.

br,
JohnD

[cuzwecan]

John, I wish we had made the repair when we repowered (Cummins 370b) . The platform the a/c sets on is rotten so I'm going to remove it and try to gain access that way , should give me some working room. I guess I will cut the rotten wood out and epoxy new in . Then I will epoxy a backing board on the back side of the bulkhead. Thanks for your help. Randy

[Charlie]

Did your rot problem come from the AC condensers or seepage from the rear cockpit/salon sill plate? I took a look at my bulkhead that the shaft goes through and it looks like a structural member. The weight of the rear cabin bulkhead sits on it. It is very heavily glassed to the bottom and sides of the hull and the stringers are glassed into it also. Maybe they changed things on a later model Cat powered boat. It is a structural component in my boat. The next bulkhead is behind the fuel tank and in front of the genny. This bulkhead at the rear of the engine room and midships sure looks like it need to be there to stiffen the hull. I do remember looking at a couple of 35 gasses many years where this bulkhead was cracked.

[thereheis]

randy where do you have your boat at ???is it at north shore???why couldn't you use fiberglasspanels for your replacement.and for your ac shelf...if you want some let me know . i know where you can get some in rockport,,,,where do you keep your boat at ????
phil

[cuzwecan]

Phil, We keep our boat behind our house on Padre Island. We used marine plywood and glassed over it for both the bulkhead and the A/C shelf. Where do you get the fiberglass panels ? The pics of your '31 looks great . Thanks Randy

[thereheis]

you can go to FULTON YACHT YARD and ask for PACO, thanks the boat will be at gatewood marine wed or thursaday this week ....

phil