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Old 02-23-2015, 09:10 PM
Blue_Heron Blue_Heron is offline
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Join Date: Jan 2006
Location: Gator Country
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Quote:
Originally Posted by flyingfrizzle View Post
I use the US composites "635 Thin resin". It is just so much easier wetting out cloth with thin resin.
Flyingfrizzle,
I'm using the US Composites 635 resin with the medium hardener. I think temperature is much of the problem. My shop has been in the high 60s to low 70s and the epoxy wets out and flows much better at 80°+. The Vinylester you're talking about should have a viscosity about 1/3 of what the 635 epoxy has. I really need to get some and experiment with it.

Quote:
Originally Posted by FLexpat View Post
Try Raka 127; its really low in viscosity - flows about like water under vacuum
Flexpat,
I've used the Raka 127 as well. Its viscosity is very similar to the US Composites 635. Combined with the 350 non-blushing hardener, it's the cat's pajamas for UV resistance. I was impressed with Raka's results here:

http://www.oneoceankayaks.com/Epoxtest.htm

Both the Raka 127 and the USC 635 are good. They both wet out the glass nicely when the temperature is right. At cooler temps, though, wet out can be a little sluggish. Part of my process has been to use a heat gun to encourage flow in the infusion when it slows down. The heat doesn't seem to accelerate the "kick" as quickly as it does with polyester resin, but it greatly improves flow.

On my first try at infusion, I warmed the resin before mixing to reduce viscosity. But once it hit the cooler reinforcements, the flow slowed, and I had a batch kick in the bucket. I think we call that an "exotherm event". I didn't want any more "events" so I just accepted the fact that it would be slow going.

The resulting laminate is very tight with a high glass to resin ratio. I just don't know if the lighter weight is worth the extra time and cost of the infusion process. I'll probably play with it a little more once the weather warms up.

Dave
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