I'm just redecorating a room in my flat and have had to unscrew a
window from its frame to do some external repairs and replace a broken
pane since the window is not very accessible from outside.

I used putty, didn't realise how long it takes to set.

I obviously want to paint the putty to waterproof it when it has set.
However, I can't do that with the window in place (hence why I took it
out in the first place).

Is there any way I can speed the putty drying process - (say with a
hairdrier perhaps) - so I can get the window back in place sooner?

Or alternatively, is it ok to paint the putty before it has completely
set.

Thanks