Hi Nedim,

I believe I did mention scuffing is necessary for adhesion. And of course I took it for granted that most know about the mold release, so a light liquid soap/water wash prior to scuffing would be ideal for most mold releases, which are PVA over wax....I lay up my glass fuses with just wax and no PVA, so one should know what kind of mold release is used to use the appropriate solvent to remove the mold release....Assuming a substrate is clean of mold release, no primer is needed, just a little scuffing...Primer is to high light flaws in the case of our models.....I use a scotch brite pad for scuffing.

Take care,
Amir