Setting the Hoops (Japanese chisels)

[Darren Brown]

Hello, finally took delivery of a set of Koyamaichi chisels. They are worth the wait, thank you Stu. I gave them a bath in lacquer thinner and lightly sanded the handles to get rid of the shiny, plasticky factory finish. Now here's where the trouble sets in. I'm trying to set the striking hoops and I'm using a hammer to compress the wood so the rings will slide on with just 1/8" exposed. I chose the white oak handles as an option. They are strong. Too strong in fact. I put a piece of scrap hard maple on my bench and tapped the circumference with the flat end of a ball peen hammer. Nothing. I wacked harder. Nothing. I transitioned to a piece of hard maple on the concrete floor and smacked away with gusto. I swear I heard the handle laughing at me. Not even a mark left behind form all my labors. Are there any tricks to this? Am I going to have to resort to removing material? How can I do so safely and consistently? I'm loath to ruin these chisels after waiting almost two months for them. Any help would be greatly appreciated.

Darren

[Jim Koepke]

Have you seen this?

http://www.toolsforworkingwood.com/store/more/setting_hoop_guide.html

jtk

[Darren Brown]

Yes Jim, thanks. Looking for any information beyond Joel's tutorial.

[Derek Cohen]

Find a pipe the same inside diameter as the hoop - I use a brass garden hose connection. Lay it over the top of the hoop, and then use the pipe to tap the hoop down into position.

Regards from Perth

Derek

[David Weaver]

On a hoop like that, I will scribe around the chisel handle with a shop knife and pare off a little bit of material (do it however you want, you can wrap tape around the handle to get an even line if you want). I hammer the wood on my handles on an anvil or on the back of a vise (care has to be taken, obviously, to not split the handles by using too heavy of blows). At least with the metal, you know

If you pare, obviously pare off less than it takes to get a tight fit, you don't really want those hoops loose, but sometimes they do not fit the handles as well as they're supposed to and you can't compress enough material.

Also, you're looking for a result, so adjust your technique as necessary to get it.

[David Wong]

Be aware that chisel hoops have "fat" and "thin" ends. Make sure the thin end is inserted first. I do not have any Koyamaichi chisels, but on some hoops the insides need to be lightly filed to smooth any burrs. I use a 350g or 500g hammer (3/4-1lb) with the end of the handle on a small anvil surface. The weight of dropping the hammer on the handle from the height of 12-16 inches is usually enough.

[Stanley Covington]

David has it right.

First, be sure to deburr the katsura' outside, and then round it on the inside, sloping towards the top and another towards the bottom, with the high spot centered on the middle of the katsura. A big contact surface is not necessary. The worse thing that can happen is for the Katsura to dig into the handle.

Kigorishi is nice, but it often won't work with really hard woods. Instead, as David said, carefully and smoothly shave down the handle where the katsura will ride to a smooth transition. A knife is best, but a file and sandpaper will work. If you remove too much material the handle and katsura fit will be ruined so be careful.

Anther method is to shrink the handle in a warm oven, and heat warm and expand the katsura in another (not hot enough to burn wood) and then drive the katsura on.

As Derek said, a piece of pipe is usefull, but I just drive them on with a hammer.

Stan