Restoring a 1963 Sea King! NEED HELP! Transom Repair...

[henleyhale]

In my years as a pool repair specialist ive seen people paint a fiberglass pool with epoxy paint and years later a new owner comes in washes the pool preps and gelcoats it, then about 5 years after that i get the call of them wanting a new gel coat job done professionally because of the blisters caused by the epoxy paint doing what epoxy does and blushing as these guys call it, thats just epoxy wearing down, id still stick with a poly layup over the epoxy for my gelcoat, ive also used gelcoat on epoxy resins and it does coat over it well, but even when ive no other good choice i know this gel coat will eventually blister up as the epoxy chalks, atleast if you skin it youll have good firm backing that will resist it untill it eventually bubbles out. I see that when guys shoot chop strand inlays over epoxy paint instead of sandblasting it right. Thats normally 10 to 15 year mark.

 

[henleyhale]

2 gallons should make you happy, home depot has it pretty darn cheap i think 50 bucks a gallon, and use a chop strand mat then for your final layup use cross stitch cloth for your final lay up, its finer pores will make for much less sanding to get it smooth for your gelcoat.

 

[zool]

In my years as a pool repair specialist ive seen people paint a fiberglass pool with epoxy paint and years later a new owner comes in washes the pool preps and gelcoats it, then about 5 years after that i get the call of them wanting a new gel coat job done professionally because of the blisters caused by the epoxy paint doing what epoxy does and blushing as these guys call it, thats just epoxy wearing down, id still stick with a poly layup over the epoxy for my gelcoat, ive also used gelcoat on epoxy resins and it does coat over it well, but even when ive no other good choice i know this gel coat will eventually blister up as the epoxy chalks, atleast if you skin it youll have good firm backing that will resist it untill it eventually bubbles out. I see that when guys shoot chop strand inlays over epoxy paint instead of sandblasting it right. Thats normally 10 to 15 year mark.

Epoxy paint is a totally different animal then laminating epoxy resin, while it is epoxy based, theres a pigment and carrier, and its extremely thinned. Gel should NEVER be applied over epoxy paint, or any paint for that matter.

also, blush is not epoxy breaking down, blush is basically uncured hardener, that reacts with the surface air, and not the resin....the chalking they get in the pool coating is uv breakdown...

I do agree its less risky to just gel over poly......

 

[zool]

Ok so with all that said about how much polyester resin will I need for the transom.The boat has a 5' 10" beam. And fiberglass mat, cloth, or roving?

For the gluing of with wood, a one gallon kit of epoxy 635 resin from USC will do, and some cabosil or fumed silica to thicken it. For the outer lams, 2 gallons of polyester 435 marine grade layup resin would do....and maybe 6 yards of 1708 mat backed cloth. You could also get some CSM, but its not really needed, its already stitched to the back of the 17oz weave.

For fairing you can use a premix like USC feather-rite or 3m, ect....or mix some glass bubbles in ur resin...

 

[acminor]

Alright guys here's the latest...

I have purchased the marine grade plywood, about to place my final order in for US Composites. In the process of making a template out of cardboard for the plywood I realized how impossible it will be to get the plywood inside this gap.

Here are my three basic options...

1. Cut a section of the back top off and separate the two halves allowing easier access.

2. Cut the transom plywood in two pieces before final installation. (Not as structural)

3. Cut off the 2 inch gap I have around where the transom meets the hull.

I'm lost and need some assistance.
Thanks in advance for any advice!
acminor

 

[Woodonglass]

Ok, Here's How I'd recommend doing it. Once the template is made and confirmed to fit, cut the first 3/4" piece of plywood to fit and then mix the PB and apply it to both the inner skin and the transom wood and then glue it and clamp it in place. You'll have plenty of room to put the one piece of plywood in the gap. If not, then you need to cut away enuf glass from the upper portions of the lip until you can can get both pieces of plywood to slip down into the opening. Once the first piece is glued in the 2nd piece can then be buttered up and slid into place and either clamped or screwed down to secure it. Any remaining voids and gaps can be filled with PB. Bottom line is, you must keep the 3-4 inches of skin left on the outside for tabbing. Cut away what you need on the top to allow the plywood to slip in from the top side if you want to salvage the boat. Don't cut the plywood into 2 pieces!!!