Japanese plane - can it have a flat sole?

[Mark Gibney]

I picked up a cheap and cheerful Japanese plane, a small 30mm production made plane.

I've tried it out and it works well as a sort of block plane, and this is how I think it'll spend it's life.

Can I use this plane successfully as it is, with a flat sole? - the way a western style wooden bodied plane would be used?

I've read up on how to condition the plane, and I may do so. But I'm curious to learn what the downside to keeping the sole flat is.

Thanks!

[Brian Holcombe]

Not really, because when the blade is bedded it will make the area behind the blade slightly proud causing it not to cut properly.

[Mark Gibney]

Yes I've read about the blade causing a bulge in the sole when it's seated, and it makes sense to relieve the area just below the blade to deal with this issue.

I have no experience of using Japanese planes, but I use Western wooden bodied planes that have simply flat soles. I googled to find if anyone uses Japanese planes with the soles simply flattened, but it seems just about everyone that'll admit to it conditions the sole in front of and behind the blade.

[Jonathan Elliott]

I don't want to highjack the thread but I'm curious about the other way around too. I can see the benefits of having the two or three contact points on japanese plane soles, couldn't western type wooden planes potentially benefit from this treatment as well? Any drawbacks?

[Jim Matthews]

Brian is too modest to recommend his own blog.
https://brianholcombewoodworker.com/2016/08/11/kanna-dai-prep/

FYI - I've set up planes at home, Japanese and Western, in the manner JE suggests. The higher "stance" of Western wood body planes takes some of the sensitivity out of smaller contact patches.

A properly waxed, uniformly flat Western plane works fine without additional tuning.

It's also a simpler thing to check.

Ultimately, no single aspect of the Japanese plane yields superior results - it's the synergy of really fine steel and wood.

[Brian Holcombe]

Thank you, Jim!

[Jonathan Elliott]

Interesting Jim, thanks!

[Mark Gibney]

Jim, the lower height and so different handling of a Japanese plane compared to a Western plane makes sense to me. Thanks for your explanation.

I think I remember reading Brian's blog on setting up a plane when he posted it some time back too.