Best way to support convex piece for stone setting?

[LydiaNiz]

I want to make a lockety-thing. The front piece will be convex and shaped from wire, and I want to have a small tube set stone on it.
What's the best method of supporting the front whilst I set the stone please? I've just ordered some Coolmorph, will that do the job?

[mizgeorge]

It's what I use for setting stones on my domed clasps, and it works perfectly for me. I press it in hard enough for it to grab the edges properly and it stays rigid without any problems. I've pretty much switched entirely to coolmorph rather than polymorph because it means I don't have to keep a heat gun plugged in as well as all the other things I seem to need to power!

[LydiaNiz]

thank you!