# How big are Japanese water wheels?



## Chef Niloc (Aug 23, 2013)

I got asked a question the other day that I could not answer, and I can't find the answer anywhere? What size are the wheels used to grind out the hollow back of traditional kitchen knives?


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## DSChief (Aug 23, 2013)

Using this as a typical wheel, my guess would be in the area of about 3 foot Dia. 
[video=youtube;aU6u80Hyw5Y]http://www.youtube.com/watch?feature=player_detailpage&amp;v=aU6u80Hyw5Y[/video]


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## Mucho Bocho (Aug 23, 2013)

Here's a good one too

http://www.youtube.com/watch?v=KQI3jXk7sY8


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## Crothcipt (Aug 23, 2013)

A couple of knives I have bought seem to have 2 different sizes of shallowness. Meaning 2 different sizes of wheels.


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## kartman35 (Sep 11, 2013)

I thought the hollow back was created during the forging process...like with a hammer.

6:55

[video=youtube;UqwxkyaSws8]http://www.youtube.com/watch?v=UqwxkyaSws8[/video]


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## Lefty (Sep 12, 2013)

I do not regret watching the second video one bit. That was actually pretty freakin' amazing to watch. I like the serious face turned big goofy grin, at the end.


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## Lefty (Sep 12, 2013)

Ok, I just watched the Carter one and it was awesome too.


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## Korin_Mari (Sep 12, 2013)

We're getting a new wheel from Japan soon and I was told that it was over 500 kgs.


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