Rolf

DIY foam comes in 2 variaties, latex and polyurethane. Acetone or gasoline will probably dissolve both. The problem is unless you use a lot of solvent, there will be a lot of sticky residue.

One is solution is to use the commerical foam cleaner as a final rinse. The commercial foam cleaner is used to clean the foam dispensing guns and are mixture of nasty chemicals.

I once had to do this for work when we had to remove a foam liner from 20 ft long tube. We were able to determine that a mixture of gasoline and liquid detergent would clean it perfectly. However this is real clase to napalm.

We ended up using a machine made to clean air conditioning ducts with a bronze brush instead of the soft nylon brushes they normally use.