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Dreadped
02-01-2011, 01:40 PM
Hi There, Thanks to you all for your previous help. I have about three questions here about a boat we are trying to restore. Any help will be greatfuly received.
We have purchased a 1970's plywood boat, it contained quit a lot of rot. The rot is all above the water line and has now been cut out. So my question is, when we come to fix the patches in at the weekend, what should we use. It has been suggested that we use epoxey, I know there are different sorts, but we are unsure what to use. The patches are from one rib to anoter and are probably about 2'x5', we will be able to clamp at the top, but the sides and the bottom will rely upon pressure. We are going to step the edge of the patches to increase the surface area.
Under the deck I also need to replace some hardwood timber that runs from the bow to the stern just inside the hull. These strips are 2"x1" and are going to be screwed and glued, I assume that I cant use any wood glue? Again they are under the deck and above the water line.
Finally once the patches are in and any inperfections have been filled and sanded we want to paint the boat, do we need to put epoxy on it first or just prime it and paint it? We are worried about humidity or air moisture penetrating the old ply and so want to get some sort of covering on it as soon as possible. We want the finished boat to be white, we are currently scraping off the existing paint back to the original ply.
Thanks in advance for your help
Simon

Peerie Maa
02-01-2011, 01:48 PM
See if your local chandlery stocks SP Systems or West Systems, both boatbuilding epoxy. See if you can get hold of copies of their users guides. You really need to study the glue properties before prepping the glue surfaces and setting up.

RodB
02-01-2011, 03:06 PM
System Three, Raka, MAS, or West Systems... epoxies... all will do everything you are asking about. Epoxy is the best glue and coating you can use for this repair. Get the System Three Epoxy Manual... (download online) and the book... "The Gougeon Brothers on Boat Construction" to have all your questions answered.

Scarfing in plywood for repairs is a straight forward process, many sources show the basic techniques, specifically two of the tech books available in the West Systems Epoxy section of West Marine, etc. You need to show some pics and provide more details to get more specific information. Basic approach... Scarf in plywood into cutout areas... depending on the overall boat construction you may have to glass over the entire plug.... fair and sand. ... prime and paint as in any repair. How about some photos... for more detailed recommendations.

Good luck,

RodB