In my experience, alumilite has a pretty limited shelf life (unless maybe you live in a desert). I would want the freshest I could get. I always figured getting it direct from Alumilite was the best bet.
Ed
Ed "Limited" to me, at least, is a subjective term. I have never used Alumalite, but have been considering trying it. What is the shelf life, and how, in the real world, does it compare in price to PR? Thanks, in advance for your advice.
Couple of disclaimers first:
1) All the following is based solely on my own personal experiences in Houston, Western NJ, and South Florida. Others may have very different experiences.
2) Resin formulations may have changed over the years and conclusions drawn on older resin may no longer apply to newer resin.
With that out of the way:
I've used 10 year old epoxy and it cured just fine. I wasn't holding together airplanes or any other type of critical structural work. It got hard and held what I needed holding.
I've used 2 year old PR resin with 1 year old catalyst (catalyst was stored in the shop refrigerator, resin was sitting forgotten in a partially empty can in the back of a shop cabinet in a non-air conditioned shop in South Florida). The resin was slightly yellowed, but cured clear (at about a 1/2" thickness).
Earlier this year I tried to use clear alumilite that had been opened 3 months previously, but stored in an air conditioned room. I ended up with really nice urethane foam. The same alumilite at 8 months was unuseable (even for making foam). The clear side had gelled and the yellow side was a dark yellow.
Last weekend I tried to use clear alumliite that was 1 year old and that had never been opened. It didn't set up. Didn't foam either. Just sat there and did nothing. I really want to love alumilite, but I seem to end up with my heart broken a lot. When alumilite does work for me, it's great. I sort of forget what that feels like though.....
Alumilite is more expensive than PR. Each of epoxy, alumiite (urethane resin) and PR have applications that they are better suited for, so I can't say one is inherently better than another. If I lived in the desert southwest I would probably use a lot more alumilite than I currently use. I use mostly PR for my projects.
Ed
