Kezurou-Kai #39

Before the industrial revolution, there wasn't a ton of difference. If you look at a plane made in the early 19th century in both Japan and the US or Europe, they'd look pretty similar. A carpenter on one continent would probably be able to orient and use tools on the other easily.

Modern metal-bodied planes do work similarly, in that both let you set a blade slightly beyond a flat sole, allowing you to remove high surfaces on wood. That's about where the similarities end.

Japanese blades are laminated steel, and quality blades are hand-made by smiths. Smiths use proprietary techniques to make blades that can maintain edges for longer than machine-forged steels. Chipbreakers are made of laminated steel as well and can keep the primary blade under tons of tension, allowing it to remain stable even when cutting against the grain. Wooden bodies allow skilled users to adjust the blade depth within microns without sacrificing stability. Wooden bodies are easily adjusted to fit the needs of the user.

To use an analogy: using a western hand plane is a lot like trying to race a Camry rather than a Porsche. It's not that the Camry is wrong - it's just built differently. The Porsche is really easy to drive into a ditch if you're not careful. It'll break down a lot, but it'll also perform much better for a skilled driver. The Camry, conversely, will be easier for anyone to drive and probably go a lot longer without maintenance. It works fine as a daily driver, and you can tune it so that it'll perform like a Porsche would, but a very well-tuned Camry is probably not going to outperform a well-tuned Porsche and a person used to driving a Porsche is probably going to complain about the Camry's handling.

> Wooden bodies allow skilled users to adjust the blade depth within microns without sacrificing stability.

I know nothing much about hand planes except what they are

But why couldn't a metal-bodied plane to do the same? Wouldn't it potentially be stiffer and more stable?

Metal bodied planes are adjusted with thumb screws and levers - they just aren't accurate enough for fine work.

Re: a woooden body, there are a couple reasons it's preferable despite the maintenance - the biggest is that they can be adjusted to fit a specific blade and chip breaker. Since the blade and chip breaker are made by hand, you can't mass produce a body and still have the tool perform. The other big concerns are weight and economy. Metal bodies are way heavier. And if they break or are damaged, can't be easily fixed. A wood body can be made in a few minutes with materials that are usually found on hand.