madmagician wrote:
I am mixing it till it has an even color through and through, even adding a bit of water to get it to a bubble gummy consistency then letting it firm for 20-30 min
This.
You can use Milliput straight after mixing. After 30 mins or so, it gets harder to work and is less tacky.
If you need to add water to get a decent mix consistency, then it implies that the putty is past its best and I wouldn't be using it for much more than terrain-sculpting and filler if I were you.
Get some
fresh Milliput, and get some Greenstuff (or ProCreate). Best places to buy these putties from is from somewhere you know has a high turnover of them! Worth spending an extra dollar or two to get them from somewhere you know keeps fresh stock. I prefer ProCreate over GS, but if you go for GS then try and get a decent amount (not the 6" GW sells), and try and get it in two bars rather than the ribbon - it keeps better and is less wasteful. Example
here.
I know that the putties are relatively expensive, but once you get used to using them, you'll wonder how you did without them!