I need a mortise bit for my slot mortiser, but finding one is not as easy as I'd expected. It needs to be LH and have a shank diameter of
10mm or less; the cutter diameter needs to be 8-10mm. All I've been able to find so far are bi-directional parallel cutters, such as
formatting link
, whereas I'd prefer a LH spiral cutter. I've no experience of the bi-directional parallel type - has anyone here tried them?