Quote:
Originally Posted by Big fish
Thanks for all the great posts as I will soon be replacing my transom as well. Did you use epoxy just to the outer skin or also between plywood? And what type of resin for the fillets? I'm told that if using epoxy everything has to be epoxy.
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You are right some what on the epoxy usage. You can't apply poly over or on top of epoxy and get a good bond. You can do the opposite and go epoxy over poly or ve resin. You can use them together if you are careful on how you apply them. On the transom I used poly to make the core section before it was installed into the boat. There was a 1/4" of glass and resin between the 2 3/4" wood plys and 2 layers of Matt around the core fully sealing the wood 100 percent. Forgot to mention I thinned some of the poly resin and hot coated the wood too. The wood will soak in thinned poly better than the epoxy. I try to always hot coat wood prior to adding glass cloth and resin. The core was scuffed with 80 grit to give it some tooth to bite a bond when I installed it. Scuffed the back of the boat the same then I used the epoxy to bond the sealed wood core to the old 40 year old glass on the transom skin. I only used the epoxy to bond the core in place only. Once that was in place I added several layers of 1708 and tabbing to the front of the core out of ve resin. The filets were made from ve resin thickened with cabosil and fiberglass rice pellets. The epoxy did not get any other resin bonded to it. It is just between the core and boat skin only. All the ve on the opposite side of the core never contacts the epoxy. There may of been some slight contact under the filets were some epoxy squeeze out around the core but bond is not as important there. I usually only use epoxy where I need a good bond to old glass or when I make a thickened puddy for gluing or bonding parts down. Mainly situations that don't require cloth. If I am laminating cloth I mainly use the ve resin. The epoxy will give you a better secondary bond to fully cured glass or old 40 year old potter glass.