Recommended Epoxy

[hdhouse3rd]

Hello All:
First post to the system. I am about to undertake replacing my deck core of my sailboat. Fortunately it is accessible from the cabin which allows good access.

I plan on using 3/8" or 1/2" Teak Plywood sheets and adhere to the deck above. I will make kerf cuts about every 6-8" fore to aft. Then brace and clamp the sheets into place.

I hope to tackle this Memorial Day weekend and with unpredictable weather in this area, Chesapeake. I think I should use a slow hardener.

I was looking at the East System Epoxy or MAS Flag. If using the East System I was considering the #835 Super Slow Hardener and with MAS the Slow Hardener.

I will need to have something that will adhere well and fill in the voids. But I will also be working overhead and need to have something not runny.

I thought of using Cabosil but someone who has done this in the past used another additive in addition to Cabosil to keep the mix from becoming too brittle.

So what may this other additive be, as he does not remember. The project when he performed it took about 2 gallons of resin. What are the appropriate mixing ratios and about how much of the additives should I use?

Thanks for your help.

Henry

[Noah's]

I am not clear on exactly what you are trying to accomplish. The deck core is most likely balsa, why are you going to replace it with Teak Veneer Plywood? Cabosil added to the resin will increase viscosity so help prevent run off, the only other additive I can think of is Cotton Fibre. This will not add flexibility but will make the glue mixture stronger. No set ratio for Epoxy to filler, just add and stir until it is thick enough. The East System 1032/835 mixture is 3:1, the 833 and 834 hardeners however are 5:1, MAS is 2:1.

[hdhouse3rd]

The current core is indeed plywood. She is a Cal 25 and this is a common problem. The factory had sandwiched the plywood between the deck and a couple layers of glass on the inside.

I am thinking I do not need the layers of glass on the inside if I get a good bond. I will be using a series of clamps and blocking the plywood into place from below. Topside I will be placing as much several hundred pounds spread out over the area to aid in bonding the deck to the newly installed ply.

So you would recommend using cotton fiber along with cabosil. But at no set ratio. That being the case what type of consistency should I look for?

I presume I would place a thin coat of epoxy on the plywood then add a layer of the thickened mixture and set it into place.

Thanks again for your input.

Henry

[Noah's]

The principal of cored construction weather Balsa, Foam, or plywood is the fibreglass skins on both sides of the core supply the strength and rigidity, the core is just the means to keep the laminates apart. By gluing plywood to the underside of the deck laminate without replacing the original bottom fibreglass layers I think you will compromise the structural integragrity unless it is supported from underneath by extra ribs and bulkheads.