Most of the Alumilite line shows shrinkage numbers of between 0.0041"/inch to 0.01"/inch. On a 30" long part, this means shrinkage of between 0.123" and 0.3". Too much.
They do have a line of lower shrinkage resins. The "Vac Master 50" and "Replicator 532". These have shrinkage of 0.0006" per inch. Over the 30" long mudflap, this would give 0.018" shrinkage, which would be acceptable. Problem is these seem to be VERY viscous. I think (as the name implies) these would need to use pressure (vaccuum or positive pressure) to give proper results.
- Frank
1984 200ES Big Red
1985 350X (x2)
1986 350X
1986 250SX
1984 Auto-X
1984 ATC70
1985 ATC70