I haven't personally used it but I do know someone that did and they said that when they heat set their mosaic, pieces would fly off from adjoining areas. Hope that helps!

OH!! Well that is certainly not part of a process I'd want to experience! Thanks!

I made a small mosaic frame during a hands-on demo at my fav stained glass store. The NoDays Rep was there to guide us. Some pieces can move a little, but the 'goo' stays malleable for a little while so you have time to reseat any pieces using tweezers.