How to Tune a Chipbreaker

The chipbreaker (cap iron) must fit perfectly flat against the iron's back with zero gaps. Any gap causes shaving jams.

Checking Fit

Clamp chipbreaker to iron and hold up to light. You should see no light gaps at the leading edge. Even 0.001" allows shavings to jam.

Tuning Process

  1. Remove chipbreaker from iron
  2. Flatten leading edge on 220-grit sandpaper (just the front 1/8")
  3. Polish on finer grits
  4. Reassemble and check—repeat if needed

Setting Distance

For figured wood: 0.5mm from edge. For general work: 1-2mm. For thick shavings: 3-5mm.

Chipbreaker distance from the edge matters more than mouth width for preventing tearout. Set it close—really close—for difficult grain.