The Japanese Gennou (Hammer)

[Brian Holcombe]

They may need to contact a vendor. So's dad does the shipping and he is always on the ball, so as soon as it arrives from the vendor it will ship....in my experience.

Since it is a small operation typically they will only communicate when something ships and when the order is placed. They will also hold the order until everything is in stock.

I think a 675g might be required with a kilt, hehe.

[Stanley Covington]

I would like to enlist your help in finding some jikatabi if you wouldn't mind lending your assistance in terms of comparing sizing.

Harris tweed is a good start

Safety toe or plain? Velcro or traditional metal tab fasteners?

What is your centimeter shoe size? There are tables on the web that compare sizes between the EU, UK, US, and Japan which uses the centimeter size. As I understand it, the Japanese centimeter size is a line drawn diagonally across the loaded (standing) footprint from the tip of the big toe to the farthest edge of the heel. But if you get those size wrong in jikatabi, the result will be unpleasant.

The store nearby has them in two styles, all safety toe. The link is to an online retailer that has more styles. https://www.monotaro.com/s/?c=&q=%92...AB%91%DC&swc=0

This retailer says he will ship internationally. http://www.uni-work.co.jp/web/jikatabi.html

I have not seen them in Harris Tweed....

Stan

[Brian Holcombe]

Thank you Stan! I'll do some research in my size, that is good information to have, as I likely would have measured incorrectly with the first go-round.

[Matt Lau]

THIS is the post that you were talking about Stan!

For those of you guys on the thread, I've been pestering Stan about gennou incessantly for the past few weeks.
I have to thank him for both his generosity of information, and his long-suffering patience.

I've been playing around with some chisels that Stan got for me, as well as a Hiroki gennou that he recommended.
The more that I use these things, the more I feel that he's probably very right on all counts.

[Stanley Covington]

I finished making a new handle for one of my favorite gennou just last night, and thought I would add some pictures of it to this post. Notice that this post is two months after the original one, so you don't need to reread the entire thread.

The head is another antique style forged by Hasegawa Kosaburo perhaps 40 or 50 years ago. It has the swell where the eye penetrates the body. This style went out of fashion after WW2, but it is a bit more functional than the style commonly seen nowadays. It weighs 60 monme, or about 224 grams (7.9 ounces). This is the perfect weight for cutting mortises and other joints using chisels with a blade width less than 19mm (.75"). Your mileage will vary, but when you have a handle fitted to your body, the hammer head often works much more efficiently letting you cut more wood, quicker and with greater precision.

The wood is Osage Orange and was a gift from Matt Lau. Matt procured the wood originally for his guitar-making endeavors. Reading online, it is used for bows (as in archery) and musical instruments. It is a very dense, tough, and especially fibrous wood, unlike anything I have used before. But it can be worked without difficulty with regular tools. The dust is not irritating, but pleasant smelling, sort of like oranges.

The color is glaring. Apparently it mellows to nut brown over time and with exposure to sunlight, or so the bowyers say. I will need to leave it in the sun for a few weeks and see.

I have no doubt this wood will be tough enough, and because the head is rather light, vibration should not be a problem. It is certainly more interesting in appearance than hickory or even ash.

Stan

[Brian Holcombe]

Beautiful!

The wood appears to have a nice shimmer to it.

My experience matches yours with regard to mortising and gennou weights. After you showed me how to make a handle I realized how much more force was being applied directly to the chisel and I no longer needed to use a 650g gennou for mortising, I use the 450g now.

If anyone is reading this and wondering what difference a handle can make, you will be shocked at how much of a difference it makes.

[Phil Mueller]

Very nice, Stan! Given this whole thread, and now that I have a spokeshave somewhat figured out, I may just take a run at a handle for a couple of old heads I have laying around.
Appreciate the posting.
Phil

[Frank Drew]

The wood is Osage Orange and was a gift from Matt Lau. Reading online, it is used for bows (as in archery).

Another name for the tree, and wood, is bois d'arc, from the French for bow wood (wood of bow). I've never seen it cultivated but you'll see a tree here and there around where I live, often along hedge rows. I turned some pieces, and it works easily on the lathe, but I'll confess that I've mostly used it for firewood (it's very good for that).

[Pat Barry]

Looks sweet Stan. Could you show us a picture of how the head is secured and also, if you tell us the length you chose for this one? Thanks

[Stanley Covington]

Looks sweet Stan. Could you show us a picture of how the head is secured and also, if you tell us the length you chose for this one? Thanks

Pat:

I will take some pics and post them tonight.

Stan

[Stanley Covington]

Pat:

I wrote a long explanation, but it evaporated, so I am just posting some pics and a drawing. If you have questions, I can try to respond.

Stan
Kosaburo60Arm.jpgGennouHandleDwg85Kosaburo20160415.pdfKosaburo60&120LengthComp.jpgKosaburo60HitsuCU.jpgKosaburo120HitsuCU.jpg

[Pat Barry]

Pat:

I wrote a long explanation, but it evaporated, so I am just posting some pics and a drawing. If you have questions, I can try to respond.

Stan
Kosaburo60Arm.jpgGennouHandleDwg85Kosaburo20160415.pdfKosaburo60&120LengthComp.jpgKosaburo60HitsuCU.jpgKosaburo120HitsuCU.jpg

Thanks Stan. I don't see any signs of wedges with your new handle so for the head attach its just a very precise fit and then snugged up by compression (tapping it home)? Is the hole roughened up a bit inside to help with retention of the head during use or is just common to make periodic adjustments to keep it in place?

[Mike Holbrook]

Thanks for the diagram Stan. I hope to finally finish my shave horse rebuild today so I can make gennou handles. I have a piece of wood from So to make the handle for the 300g Hiroki.

I don't know if mine will look as nice as Stan or Derek's though. I tend to finish my handles using a microplane that leaves a rougher pattern in the handle surface. Does this type handle benefit from a smoother surface?

[Stanley Covington]

Pat:

No wedges, no roughening, just a very tight compressed fit driven with many hard hammer blows. This is why the butt needs to be domed, or the handle may split from the butt.

Don't have anything to do with the silly practice of kigoroshi on gennou handles.

Stan

[Stanley Covington]

Thanks for the diagram Stan. I hope to finally finish my shave horse rebuild today so I can make gennou handles. I have a piece of wood from So to make the handle for the 300g Hiroki.

I don't know if mine will look as nice as Stan or Derek's though. I tend to finish my handles using a microplane that leaves a rougher pattern in the handle surface. Does this type handle benefit from a smoother surface?

I doubt you could make the curves with a plane unless it really is tiny. Spokeshaves work well for me. Sandpaper works well for finishing, too ......

Stan