Epoxy Floor Replacement

[boatingwithmyselfs]

I've been rebuilding the floor of my 1979 Webbcraft 18' Tri-hull and have reached a point where I have a few questions. I've read through tons of the stickies and other posts but have confused myself with the different recommendations for epoxy vs poly resin.

So far, I decided to use marine grade plywood and the West System epoxy (105-B and 206-B) for the floor. I cut out the old floor with a circular saw and found rock solid stringers wrapped in fiberglass, so I haven't messed with those other than to fill some holes with epoxy. The new floor received two coats of epoxy on the bottom and sides and then was screwed down to the stringers. All holes were pre-drilled to a diameter larger than the screws and filled with epoxy, then I pre-drilled the epoxy to a diameter smaller than the screws. The gaps between boards and between the hull and the floor have been filled with peanut butter made with a blend of epoxy and fumed silica. I bought and cut to size a roll of 1708 biaxial cloth for the tabs and floor.

So my questions:

1) If I understand other posts correctly, the epoxy will not dissolve the CSM on the bottom of the cloth the way that poly resin would. Is it okay to lay down the 1708 with epoxy or do I need to buy a different cloth?
2) Assuming I can use 1708, should I do the tabs first and then the floor, or the floor first and then the tabs?
3) Also assuming 1708 is okay, should I wet the floor with epoxy and then lay the 1708 over that, then add another layer or two of epoxy over the 1708? Do I need two layers of 1708?
4) When laying the 1708, do I overlap it or just butt it up to the last piece?

Thanks in advance for any help y'all can offer this newbie.

 

[kcassells]

1) If I understand other posts correctly, the epoxy will not dissolve the CSM on the bottom of the cloth the way that poly resin would. Is it okay to lay down the 1708 with epoxy or do I need to buy a different cloth?
---it'll work but move on to 1700 when all gone.

2) Assuming I can use 1708, should I do the tabs first and then the floor, or the floor first and then the tabs?
--- Tabs 1st, I don't think it matters cause you'll probably be fairing it out later.

3) Also assuming 1708 is okay, should I wet the floor with epoxy and then lay the 1708 over that, then add another layer or two of epoxy over the 1708? Do I need two layers of 1708?
---Floor should be wetted out and dried. Then wet out prior to glass install. Wood will suck out glue and leave glass dry. Fill all voids on edges and wet out edges real good. They rot pretty fast if not.


4) When laying the 1708, do I overlap it or just butt it up to the last piece?
---Tabs should be overlapped but deck pcs. can just meet ea. other. Overlapping makes a better joint.

 

[chevymaher]

The boatworks guy did show on just this. 1708 works fine with epoxy it just takes alot more resin to do it. Than just using poly to wet it out.

 

[boatingwithmyselfs]

Thanks for the quick replies. Based on the above I'll plan to wet the deck and let it dry one day, then on the next day rough the cured deck and clean for 1708 installation. Then I'll install tabs and then the glass on the floor. Do the tabs need to cure before doing the floor or can I re-wet the floor and lay the 1708 the same day as the tabs as long as the tabs are tacky? And is one layer of 1708 on the floor good or do I need two?

 

[kcassells]

Good plan. Actually wet on wet is a stronger chemical bond. The other is referred to as a mechanical bond. If you get to wet on wet I do it whenever I can.
1 layer of glass is fine. Make sure you wet out and glass {optional} the underside.

 

[boatingwithmyselfs]

I recall reading before that wet on wet was better so I already did two coats on the underside and sides and did wet on wet for that but no glass. For the topside, is it still better to let the first coat cure and then scuff or should I plan to do wet on wet for that as well? I've got rain in the forecast for the next few days but hopefully I can find a dry day to get the tabs and topside in as a wet on wet application.

 

[boatingwithmyselfs]

The boatworks guy did show on just this. 1708 works fine with epoxy it just takes alot more resin to do it. Than just using poly to wet it out.

Thanks for the tip. I found a few videos on his site that were very helpful. For the benefit of others, check out the videos listed below. [h=4]Can Gelcoat And Epoxy Bond? posted 12/18/14[/h] [h=4]Gelcoat / Epoxy Bonding Results posted 1/6/15[/h] Can CSM (Chopped Strand Matting) Be Used With Epoxy?? posted to youtube on 3/10/19

 

[kcassells]

Wet on wet is a term referred to when glass is applied over each other, not glue.
yup--let the first coat cure and then scuff

 

[boatingwithmyselfs]

Will do. Thanks!