As the title suggests, I wonder if anyone has ideas for breathing new life into old/dry/crumbly putty. I've got a tube of white Squadron that I bought maybe 2 or 3 years ago and while it still gets the job done, it's not so easy to apply anymore. Rather than spreading it like peanut butter or dotting a bit in place, I need to forcefully press the chunky stuff into the gaps. So what would you do in this situation?

Liquid cement or laqcuer thinner can be used to make putty more workable: squeeze out some, add cement/thinner and mix. It's quite a hassle as you need to do it every time you use the putty. I'd just buy a new tube.

You could put it in a glass bottle and add cement or lacquer thinner and have it ready each time you need it .

Buy a tube of auto-body putty. $6 for a lot and it works a lot better than Squadron.

I have bought a tube of Sikkens automotive putty(I think spot putty grey and pink) tube. very fine beige colour. Works like a bomb, I also thin it down with MEK and brush into / onto small areas. Normally squeeze a piece onto my humbrol 78 cockpit green tin and leave it there. when it hardens I just add MEK and mix with the #1 paint brush I use. Oh yes dries quick and sands quite nice too
cheers