I've been skimming a few spots with putty, and now 20 hours later it is still soft. Clearly I haven't used enough hardener. So I will be cleaning that out as best I can today. The product says 50 to 1, I've heard people say 10 to 1. I followed the directions at 50:1, and the putty was still more or less cream coloured with a very slight shade of pink. What colour am I aiming for? I imagine that with 10:1 I will end up with a distinctly pink putty. Any advice?