On Jun 22, 11:27*am, "N_Cook" wrote:
Needless to say no original packing. Sub-mm bits with 1/8 inch shanks. Other
than by breaking easily, using hand drill rather than pedestal. Would
carbide just make a small grinding disc skitter trying against the shank-end
of a flute, or different spark colour perhaps ?

My 1st suggestion would be to check them with a magnet. I don't think
carbide is magnetic

CarlBoyd