Help: how to prevent Future Floor Finish from cracking?

I have been using Future Floor Finish over Tamiya acrylic for quite sometime now. It had worked brilliantly. However, about a years ago I finally ran out of the original bottle and got a new one. The resulting clear coat always CRACKS. I always make sure the bottom layer is completely dried before applying Future. I have tried thin layer, thick layer, thinning Future with water, thinning with isopropanol, straight from the bottom, decaled, not decaled, polished and unpolished. They all cracked on me!:mad:

I noticed that the cracking begins to appear only after 2-3 months. Is it a just bad batch? Or have I done anything wrong? Or is my fiance secretly toying my models?

Thanks in advance!

Future is really not intended for modeling use. It is what it is, for floors. Although people use it as a clear and get good results, yourself included, I personally think if you used a proper modeling clear you would see a big difference.
Anyway to answer your original question. Maybe they changed the formulation...??? If you are using it exactly as you used to and had no problems with it, then maybe the newer bottle you have is not the same as the old..??

I noticed that the cracking begins to appear only after 2-3 months. Is it a just bad batch? Or have I done anything wrong? Or is my fiance secretly toying my models?

No, it is simply the wrong product for the job. Future is a floor polish. It is not intended as a hobby or automotive clearcoat, and should not be mistaken for one. You're using it in an application that it simply was not designed for. Future can and often will crack, craze, or fog.

If you want a good acrylic clearcoat, try Tamiya X22. Thin it only with X20. Future does have its uses, even in car modeling. But if you're using it as clearcoat, it always reserves the right to behave badly.

Thanks for the advice. I chose to use Future mainly for health reason. I'm working in a biochemical lab and am constantly exposed to nasty organic solvents almost on daily basis. I thought I could use some fresh air at home. I've always wanted to give 2K urethane a try. Perhaps now is the time.

Oh, I probably need a decent respirator too.

Thanks for the advice. I chose to use Future mainly for health reason. I'm working in a biochemical lab and am constantly exposed to nasty organic solvents almost on daily basis. I thought I could use some fresh air at home. I've always wanted to give 2K urethane a try. Perhaps now is the time.

Oh, I probably need a decent respirator too.

Yea just get a good respirator and you'll be fine.

I agree with the guys above that Future is far from the best medium in many technical respects and therebare a lot of alternatives that can give maybe better and more consistant results. HOWEVER, the specific problem you are describing rather looks as if it is down to the specific bottle/batch you are using no? After all, you yourself said that you have used it in the past without this happening and I look at all SeanyG's incredible builds covered with future and have yet to hear him complain of cracking...

I think that if you like using it for whatever reason and are reluctant to switch away from it, get yourself a new bottle and give it a second chance ;)

As MPWR says, X22 is a viable and non-toxic alternative and I can also reccommend Gunze Mr. Top Coat as a very good clear that is fairly mild.