My suggestion would be to look around for some very old stock - or keep new stock for a few years. Some formulations begin to polymerise and go pretty solid after a while. I have a tube of silicone so stiff that I have to all but put it in a vice to get any out, but it does come out under considerable pressure, albeit very slowly (viscocity now just a little higher than solid plastic!)Doug Coulter wrote: If anyone finds a non creeping formulation, I'll be all ears.
Actually, once it begins to come out, you can wipe it with a finger and push it around on your finger pad like chewing gum and it begins to flow a bit more that the impression given during the 'pushing-out'.
(It might also be because the tubes I bough a few years ago were the cheapest I could find, whereas the more expensive stuff is more stable and doesn't polymerise like this?)