Casting car bodies question

[Radio Joe]

Hey guys

I want to try casting some car bodies. I have cast stuff before using hobby lobby supplies (Alumilite). Every time I cast something it comes out hard, but sticky.

I have tried heating up the mold, tried keeping a heat gun running on the mold while it hardened. I tried more hardner, less hardner and it always comes out sticky on the surface. On past things it hasnt been a big deal- i sand it off and then paint but on a car body which is already thin I think it could be an isssue.

Is it the cheap-o resin from Hobby Lobby or am I doing something wrong?

[1320wayne]

I have used Alumilite resin for quite some time now and when I was new at the process and trying to figure out the mixing forumlas I had this happen as well. It is caused due to having the mixture off. I use a 1:1 mixture and it always comes out fine. Not enough of the part B will bring about a sticky pour.

[Modelmartin]

Is that 1 to 1 by weight or volume? I recommend getting something better than alumilite. I use a polyol type resin and it is not in the least sensitive to mix ratios as long as you are in the ball park.

[Radio Joe]

Is that 1 to 1 by weight or volume? I recommend getting something better than alumilite. I use a polyol type resin and it is not in the least sensitive to mix ratios as long as you are in the ball park.

The mold making stuff is Alumilite but the resin is generic stuff they sell at hobby lobby. where do I find the polyol resin?