epoxies??

[Helen]

Hello Lori,
thank you for answering my last question regarding patterns, it really helped.
Another thing you recommend is Kulis Karvit. Do you mix that half and half? I put some on a wire to make pads for a hawk's foot and that was 8 hours ago. How long does it take this stuff to get hard? It's sorta rubbery now, but somewhere I read it sets in :30min. This will definitely be overnight. 'course it is 80o out here (Vancouver, WA.). Will it get as hard as quickwood?
Thanks again,
Helen

[LCorbett]

You're very welcome, Helen!
Yes, you mix the Kulis 50/50. I find that temperature and humidity play some role in the drying of the stuff. With Kulis, I generally plan on letting it cure over night, so it's the last thing I do for the day. I like to let mine set for 24 hours, no matter what the directions say...
It shouldn't really be rubbery after 8 hours. A couple things could be the issue:
#1. Aforementioned heat an humidity (Kulis is workable with water, so it stands to reason humidity will affect the drying time a little bit). But still - I haven't found it to be a large factor.
#3. You worked it heavily - with water. Gonna take a bit longer to set. Eight hours agains, sounds a little extreme.
#3. The mix wasn't 50/50. There is a slight bit of "forgiveness" in the mix, but this is the biggest factor for set up time...too much of the resin portion will cause it to be rubbery, or not set up at all.
#4. The two parts weren't mixed thoroughly. This will cause the Kulis to "flake" when you go to carve/sand it...the stuff that flakes out is usually the resin portion.

I've been using a different two-part putty these days. It's called Aves Apoxie-Sculpt. Like Kulis, it's a two part putty, BUT, you can buy it in two forms...slower set-up (about 2 hours (if memory serves me) - but again, I like to let it cure over night), and a faster set-up (about 30 minutes). These are set-up times, not curing times. Meaning they will start to harden, and become more difficult to work.

I use the slower form when setting eyes, the quicker form for seam disguising, feet, etc. Be aware, tho, that the same set of issues can apply to the Aves, as well. BUT, I have found that the Aves is more consistent, and I feel that when it cures, it's harder.

Here's a little tip for all the two-part putties mentioned...when I'm combining my parts, I add just a little more of the hardener to the mix 5-10% usually. I find that I've cut down on the "rubberies"...but it does tend to set up just a bit quicker...