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Re: cloth and glass estimates
By:Jay Babina
Date: 3/31/2011, 2:37 pm
In Response To: cloth and glass estimates (Paul G. Jacobson)

Many times I read on this site and other places about epoxy not giving any strength. Try snapping a scrap of 1/8" Luan or Okume and then coat a similar piece on both sides with epoxy, let it cure for a week and try to break it.

Take 2 pieces of plywood and coat it with a layer of glass with epoxy. Fill the weave on the 2nd piece. Then put a cement block on it and drag it down the street with a rope and see what happens. The un filled glass one will be shredded apart.

We work a balance with strength / weight by using a binder and glass fabric in combination. But don't under-estimate the abrasion resistance that the epoxy supplies. I know when I repair a boat, the sander is slowly grinding away as it tries to work through the hardened epoxy and once I hit the glass, it easily cuts through it. The glass is a girdle holding the boat together and becomes a puncture proof fabric because its fibers are held in place. But epoxy itself is a super strong chemical and many applications use it alone to make castings that you can actually tap for a bolt or as a stand alone part quite able of taking all kinds of stress.

Paul, Im not jumping on you, - you gave a lot of good advice. I just want to clarify a misunderstanding about the strength epoxy gives to our boats.

Messages In This Thread

Material: How much fiberglass?
Eddy Anderson -- 3/29/2011, 6:34 pm
Re: Material: How much fiberglass?
Jay Babina -- 3/29/2011, 6:51 pm
cloth and glass estimates
Paul G. Jacobson -- 3/30/2011, 8:21 pm
Re: cloth and glass estimates
Jay Babina -- 3/31/2011, 2:37 pm
epoxy "strength"
Paul G. Jacobson -- 4/2/2011, 2:37 am