does anyone know a way of removing black cascophen from the top of deck beams without planing it off. Tried Sanding but it seems to hardly touch it .Thanks
It depends whether you are merely trying to remove a bead of glue that is attached to the surface, or the brown discoloration that has stained the grain itself.
For the former I'd suggest careful chiseling with a very sharp chisel, used like a hand plane. Sanding just seems to melt the glue, clog up the paper, and spread the stain through the wood.
If the stain has got into the wood you really just have to decide how much it matters or whether you really want to sand the wood down to beyond the limit of the stain.
It would be handy if there were some kind of solvent that would dissolve hardened cascophen.