Posted March 11, 2014 - 09:50 PM
depending on the gauge or thickness of the material, all of the above will work. However, thin light gauge material will warp if you get it hot. 1/4" wall frame sections and heavy wall stuff can be mechanically cleaned with no worries about warpage. Mechanical cleaning includes flapper wheels, 3m wheels, wire brushes sandblasting etc.
On thin sheet metal mechanical cleaning can cause parts to get too hot, and warp. the wire brush is about the safest way to do it. I've used stainless and brass cupped wheels for paint stripping, both have worked ok, except for the thousands of metal wires in my clothes.
The 3m wheel on a drill will work ok too, if you move quickly to avoid heat build up.
sand blasting will warp thin pieces, it build up heat quite quickly.
The 4-1/2" flapper wheel will warp thin pieces too if the paint is thick, or you stay too long in one place.
I've used industrial grade aircraft stripper on cast and sheet aluminum, steel, and plastic, with no problems except the cleanup. Standard off the shelf Polystrippa will work fine on thinner paint coatings, and probably heavy PC with multiple apps. It worked OK on 35 year old sun baked tractor paint.
Low pressure organic blasting (soda, walnut shell, etc.) is pretty safe. I've used walnut shell to blast engines with no problems.
Cvans and boyscout862 have said thanks