Wiley Horne
Hi David,

To add to your point,

“ and the abutments have to be precise enough since there's no wedge - precise enough to keep the iron tight but not prevent it from getting it to the end of the plane.”

Western and Japanese woodies share this problem of precise fitting of the iron within the abutments. The Japanese plane has evolved to solve this problem by having the iron slightly sprung in the abutments. That’s how some practitioners are able to use the plane with no chipbreaker. The iron comes from the smith with a slight curvature (1-3 thousandths), based on measurements I made of a half dozen kanna some years ago.

Sometimes you see the western woodie with the wedge slightly sprung—scraped just a tiny bit hollow, so as to ensure a tight fit top and bottom of the iron. To be sure, we have also seen western woodies where the wedge was not sprung, just perfectly fitted its whole length. But overall I find it an interesting comparison of two ways to solve the same problem.

Not suggesting the Japanese iron is smithed with this curvature to aid fitting—no, surely it is a natural product of the welding and heat-treating process. But over time, the dai makers (who were often the users) figured out how to use this blade curvature to advantage.

Wiley