Hypalon is very resistant to caustic soda which is an ingredient of some
non-solvent based strippers. Can be purchased as drain cleaner. Make a
thick paste with, say, polyfilla and 5-10% caustic soda and leave in contact
under a clingfilm skin to prevent drying out. leave for variable period on a
test piece and hose off. Could take 12-24 hrs. I used a commercial caustic
soda stripping paste to get red lead off orange hypalon with no ill effect
on the membrane

Dave

"Nigel Rudgewick-Brown" wrote in message
...
I have a rib with lettering painted on the side with inflatable boat
paint.
The tubes are Hypalon.
I have tried acetone which just softens the paint
Any suggestions?