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Re: Epoxy: US Composites Epoxy?
By:Pete Rudie
Date: 12/30/2001, 1:42 am
In Response To: Epoxy: US Composites Epoxy? (Brian Nystrom)

I haven't used this product, but here are a few thoughts about epoxy.

Epoxy manufacturing is a mature industry. There are no magic shortcuts. All the "manufacturers" we deal with in boatbuilding epoxies are actually "formulators", who buy their materials from the actual manufacturers, blend them to obtain desired physical characteristics, and then resell under their own label. 90% of all the epoxy resin sold in this country is manufactured by one of 3 companies - Dow, Shell, or CIBA-Geigy. These 3 and several other companies make hardeners. But they all act more or less like OPEC. Unless you are a HUGE user, you don't get much of a price break.

There are lots of diluents used with epoxy and hardener, to tweak physical characteristics and reduce the cost of the mix. Nonyl phenol is one, and butyl acetate is another, but there are hundreds. These diluents are generally far cheaper than epoxy and hardener. Ergo, if you have a cheap product, it has lots of diluents. It's sort of like bulking up bread by adding sawdust.

It is not possible to tell what this epoxy is designed for. Maybe it's used for missile nosecones, and if so it should be more than adequate for boats. But then again it may be designed to make computer circuit boards, and if so electrical resistance would be a lot higher on the priority list than physical strength.

Pardon me if I'm boring everybody with this concept, but I would rather not risk the hundreds of hours of woodworking involved to save a few dollars on a questionable resin. The idea of having something break at an inopportune time and place gives me pause for reflection too. YMMV, but I'm for sticking with a known product, even if it costs a little more. RAKA, for instance, sells a 3-gallon kit for $118; a little pricier, but they have a good reputation on this BBS for service and performance.

Maybe I'm too conservative here. If your risk management algorithm says go for it, please let us know how it turns out.

: Has anyone used this stuff? Their 3 gallon kit with "thin" epoxy
: and slow hardner is only $82.50! If it's any good, it looks like a heck of
: a bargain.

Messages In This Thread

Epoxy: US Composites Epoxy?
Brian Nystrom -- 12/29/2001, 9:02 am
Re: Epoxy: US Composites Epoxy?
Pete Rudie -- 12/30/2001, 1:42 am
Re: Epoxy: US Composites Epoxy?
LeeG -- 12/30/2001, 12:33 pm
Re: Epoxy: US Composites Epoxy?
John Schroeder -- 12/30/2001, 4:41 pm
Re: Epoxy: US Composites Epoxy?
Chad Smith -- 12/30/2001, 4:26 pm
Re: Epoxy: US Composites Epoxy?
Brian Nystrom -- 12/31/2001, 1:07 pm
Re: Keep Looking Brian
Shawn Baker -- 12/30/2001, 12:29 pm