Sharp Angles

I am in the process of building a one-piece epoxy deck. I built a plug and pulled a mold from it. I had a problem with the glass (1 1/2 oz. matt and polyester resin for the mold) not conforming to the tighter curves and ended up with a days work tiddling up the mold. That done I am now concerned that I will have the same problem with the epoxy deck. I am planning on 1 lay of 6 oz. cloth with a little reinforcment here and there. How can I get the cloth to lay nicely in the sharp corners? These are around the hatches and all around the sheer line. I thought of using a micro-balloon putty to ease the radius of the curves but that might weigh to much. Any ideas would be appreciated.

Don, laying up the mold would be facillitated by using fiberglass putty near any sharp corners as well as thin glasscloth 3/4- 1 oz… Sharp corners are not a problem, generally speaking, for an epoxy glass layup but you’ll need to use thin enough material to con form well. Using something like the lite weight West system filler might work better than microballons in the long run. But you’ll have to use something where the material will not lay in proberly.
You can make a test on the mold but that will require re waxing once you remove it:you can lay up a small area and see if you can visually tell that the material is working then remove it with acetone or T12 after the test; saves wasting a part.If you have thin glass on hand and some filler you should be able to do almost anything.The thin glass is harder to work with than 6 oz. so you’ll probably want to practice first.

Doug Lord
High Technology Sailing/Racing

Don, if you do it in layers make damn sure you know your epoxy manufacturer’s “window” for continued layup: some windows are as short as one hour. If you exceed the window you’ll have a poor bond between layers.Generally, a window for continued layup is 1.5-3 hours with the 4/1 stuff I use from fiberglass coatings.(thin laminate @ 68 degrees)
There is no reason on a model layup that you shouldn’t be able to do it all at once–just practice with the thin stuff first. If the corners are real sharp then cabosil would be preferable to a lighter filler since it is much stronger and it won’t take much…

Doug Lord
High Technology Sailing/Racing

i used to have the same problems. but a friend of mine who builds rc submarines turn me onto the stuff. look into an epoxy called mgs 310. it is the same epoxy used to make aircarft wing composites. and you do not have to worry about curing time. it will cure in 24 hours. but by mixing the hardener you get a working time of 1/2 hour - 6 hours. and it is storng enough to fix a baseball bat. (i was bored) the big problem is the mix. you have to be with in .2 grams. the mix is 100/38. 100/40 will work too but it does not cure like 100/38 does
what i do is brush on the epoxy firt then press the cloth into the resign. and since i can get a 2 hour work time. i can keep an eye on the hull just to make sure it does not puddle are get air bubbles.
I have worked with west system but i find the mgs epoxy to be better
good luck