Body filler Cracking

[muttley]

We'll as some of you might know I've been building a Scania Longline for what seems like forever . I'm trying to move it forward in between work commitments but the problem I'm having is where I put a piece in the middle of the Topline roof to extend it the filler cracks after no time at all. I haven't built it so that it has masses of filler in and I've also braced and strengthened the inside to stop it flexing . I thought of putting fibreglass resin inside to make it stronger but I think the heat it gives off while curing could end up warping the sides.
So any ideas what I can do to get rid of the hairline cracks where the joins are after filling and sanding it ?

[rebekah_harper]

Here is the best thing for filler.

http://www.tomps.com/polyurethane-fast- ... -1093.html

It's mixed by weight and using a small set of scales with those little tablet cups.

These a little video on my Facebook page RC TRUCK DESIGN which shows it being used by me.

Buy the fast cure and once mixed you can gauge the thickness then apply it as needed. Sets as plastic sands great and sticks great.

[muttley]

Cheers Rebekah I knew you'd have a solution

[rebekah_harper]

It's really great stuff.

If you use those plastic squeezy sauce bottles. You can manage the quantity into little cup on the scales. Means you don't use loads.