Plywood pilothouse repair

[wingspar]

I'm looking into purchasing an 1970's trawler where the superstrcuture is glassed over plywood. Several area have leaked and is starting to rot the inner teak plywood. What is the proper method for repair as simply removing all the interior plywood doesn't seem like a good idea as the roof would cave in.

Dave

 

[FF]

What is the proper method for repair as simply removing all the interior plywood doesn't seem like a good idea as the roof would cave in.


Cut off the entire house and rebuild it , in plywood for the short life, or in foam core for an unlimited service life.

Otherwise cut 2 ft wide slices out and replace them one at a time.

The cost of all this work is why these boats can be well done , well equipped and under $20K.

For a real patch job make up your own Git Rot and inject a few gallons where its really punky.

Don't venture out in the blue water afterwards.but the loop should be fine.

FF

 

[wingspar]

What I'm thinking is removing 2 to 3 foot sections of the teak faced plywood. I'm hoping the remaining fiberglass is thick enough to hold its shape. Build this up to about 1/4 inch with additional fiberglass and epoxy. Glass in some new 3"x3/8" fir battons running vertical spaced every foot or so. The new plywood would then be attached to the battons. Working around the house until all has been replaced.

Dave

 

[LarryW]

I've alsways believed if its rotten take it all out. before its over you'll be doing it anyway.

 

[Phil Fill]

You can repair from either side, so I would repair the side that is in the worse shape or has to be replaced.* The area cut out should be no larger than you can reach/work and back/in to good wood about 6 ft to secure/anchor into.* Save the old pieces as a pattern. You can by 4X8 pre make fiber glass sheets that you can epoxy to new plywood or epoxy the old.* ******

*
If you need more information/help let us know. We can sort of walk you through it. I have replaced the entire PortugueseBridge from the inside, under the 4 salon windows from the out side and same areas in the roof from the in and out side.* Not hard or expensive if you do it yourself. *

 

[Chris Foster]

Take a look at the CHB owners' group on Yahoo:

http://groups.yahoo.com/group/CHB/

There are numerous threads on different ways folks have done this repair - from filling with an epoxy slurry to cutting out the interior glass and replacing the plywood from the inside to doing the same from the outside. There are a few links to photo sites with detailed step-by-step photo logs of the whole process.

Sounds like you may have a little different situation - I guess you don't have a glass sandwich but rather just a plywood structure with glass on the outside?

 

[FF]

The hassle with GRP is always stiffness.

The fiberglass thin skim that was supposed to keep the tain out for a while is not stiff enough even with " Build this up to about 1/4 inch with additional fiberglass and epoxy".

You will do best simply making light cuts in the inner surface of the replacement plywood , shmeering it with thickened epoxy (so it wont drain while curing) and pushing it in place to cure.

Finish the inside with paint or purchase a teak vineer and contact spray it up.

For a more EZ to clean surface formica is the traditional.

FF

 

[Baker]

Formica, baby, formica!!! It is also quite common to just rip it out and replace with formica. Obviously you want to keep enough teak trim to give that yachty feel but it can be tastefully done and still look quite good and last forever. I do know that boatyards will do this for you as well...... my wife is related to the business. Their yards do "formica jobs".

 

[wingspar]

CHris:

What I'm looking at is a plywood house that has been fiberglassed over similar to the Pre 1978 CHB 34. I've tried to get into the CHB forum but need to be approved by the moderator.

Fred:

Removing the old plywood and building up the thickness of the outside fiberglass and installing vertical battons upon which the new plywood can be screwed to and a teak veneer glueed over it should be plenty stiff.

Sorry no formica in my boat, that is assuming I buy this one.

Dave

 

[FF]

Removing the old plywood and building up the thickness of the outside fiberglass and installing vertical battons upon which the new plywood can be screwed to and a teak veneer glueed over it should be plenty stiff.

We will see when the first 5ft wave top climbs aboard .There a BIG hammer!

FF