5/8” Mortising Bit for Hollow Chisel Mortising Machines

The HMC625B is a 5/8-inch mortising bit for hollow chisel mortising machines. The 5/8-inch size is used for wider mortises in heavier furniture construction, door frame stile-and-rail joinery, and light timber framing applications where a larger tenon width is needed for structural strength. At 5/8 inch, this is a medium-heavy mortise size — the bit bores the round core while the matching HMC625C hollow chisel squares the corners. The larger diameter requires more chisel plunge force; confirm your mortising machine has sufficient capacity for the 5/8-inch chisel-and-bit combination. Use HMC625B as a replacement bit; order HMC625S for the complete set. Pairs with the HMC625C hollow chisel.