epoxy cure time w/ infusion?

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#1

With vac infusion, is there a way to speed up the cure process? Since work time is relativly short (just suck n’ go from what it seems) something with a lower cure time would be ideal over a longer hardener yes? No working it by hand, so your window of work should be less than 10 minutes once the resin is mixed…

Also, for the first time I’ve got a part that the epoxy resin didn’t cure. It’s been 2 days, and it’s still tacky. My guess is that the ambient temperature fell below the 72degree (whats on the can anyway) threshold. I’m sure the mixture was right, is there anything I can try to salvage the part? It’s been below the 70deg mark outside the last week, so I need to look at my options.

Thanks!
James

#2

the only way to make epoxies really cure faster is just get the fast cure hardener for it. I usually just leave everything overnight, pop and trim in the mornings and that schedule works wonderfully. I have learned in the game that if you try and hurry the process then you are going to have a lot of parts going in the trash.

#3

Along with a fast hardener, you can try heating the epoxy components and the mold.

As far as the uncured part, try adding a little heat. Also, even though you may have measured the components exactly as specified, if you didn’t mix them thoroughly you will see similar results.

  • Bob
#4

I totally agree with the above post. For the extra heat (speed curing up) we use quartz work shop lamps as they can throw out some serious heat.

You can also go to PER as it will cure faster…

#5

little update:

I put my 3 hallogen lamps on a part of the mold yesterday for about an hour. They were still sticky when I removed the heat (~100deg surface temp) but a while later they’re much harder than the surounding area. I’ve had them inside my house since yesterday, but overall the part still did not cure :frowning:

I’m thinking this run was a wash. I’m going to put it back under heat for a while to see if I can salvage the part.

For those in colder climates, what do you do when curing your parts?

James

#6

I know Doug, out in Michigan, uses heat lamps as well. He used to have a heater but it burned down his shop last year when he left it on overnight. It wasn’t pretty.