karoliina.t.salminen
Well-Known Member
I have been experimenting with mold fabrication with CNC. The most inexpensive material for the block to be carved happens to be the blue styrofoam. However its melting properties causes a surface finishing problem.
I have figured out that I can directly paint over the foam using solvent free epoxy primer. However, the problem with that is that the epoxy primer without solvent is very thick. All small details get rounded, and even if I sand and polish this paint, the result is not exactly the shape I was intending.
What would be the best way to cover the foam (plug) to get mirror finish without compromising the shape?
I saw pictures of molding epoxy spread at something like 1 inch thick layer and then machined again directly to mirror finish. Would that be the optimal wy or is there some less material requiring method? I would need quick automated mold fbricatin technique for rapid prototyping of wings in RC scale and later full scale. Typically mold making instructions on web have antiquated hand labor techniques which by definition does not lead to rapid prototyping.
Or should I use urethane instead and finish it with paint that has solvent resulting thinner layer?
I have figured out that I can directly paint over the foam using solvent free epoxy primer. However, the problem with that is that the epoxy primer without solvent is very thick. All small details get rounded, and even if I sand and polish this paint, the result is not exactly the shape I was intending.
What would be the best way to cover the foam (plug) to get mirror finish without compromising the shape?
I saw pictures of molding epoxy spread at something like 1 inch thick layer and then machined again directly to mirror finish. Would that be the optimal wy or is there some less material requiring method? I would need quick automated mold fbricatin technique for rapid prototyping of wings in RC scale and later full scale. Typically mold making instructions on web have antiquated hand labor techniques which by definition does not lead to rapid prototyping.
Or should I use urethane instead and finish it with paint that has solvent resulting thinner layer?