Anyone use the Nezumi chisels?

[Matt Lau]

I'm building a guitar under the guidance of Randy Angella.
He likes to use carbon fiber, both as veneers and spruce/carbon/spruce sandwiches.

For the past two years, I've been thinking of upgrading from my (cheapest Japan Woodworker house brand) japanese white steel chisels to something nicer.

Any thoughts on the Nezumi chisels that Stu carries vs the PM-11 stuff?
He sent me a nice email this morning, but I'd like some third party opinions (no offense, Stu).

Also, I'm curious about thoughts on sharpening these.

[David Weaver]

I have never tried one, but if stu tells you something, I can vouch that it will be as or (on average) more honest than anywhere else.

Those are HAP chisels. You'd have two options to sharpen them:

1) something extremely hard like diamonds or CBN (stick with diamonds, CBN is a waste of money when there isn't a heat issue)
2) garden variety waterstones but grind the steel to the edge and work very little metallic area with the stone (i.e., microbevels).

I don't know how it would compare to PM11, but if you like japanese style chisels, it would be a pretty easy decision for me.

For cutting artificial materials, I'd bet the HAP would be great. PM11 might be, too, but someone will have to confirm it.

[Jim Matthews]

I'm completely lost, trying to read the response -

What is meant by CBN and HAP?

[Jessica Pierce-LaRose]

I'm completely lost, trying to read the response -

What is meant by CBN and HAP?

I had the same thought. Took me some googling - CBN is (I believe) Cubic Boron Nitride - an abrasive that is better than diamond in some applications when made properly. I dunno - I didn't look too much into it.

HAP I guess is referring to Hitachi's HAP-40 steel (they may have other numbers of "HAP" steel) which from what I quickly read I gather is a powdered metal steel, that may or may not be M4.

[Sam Takeuchi]

I had the same thought. Took me some googling - CBN is (I believe) Cubic Boron Nitride - an abrasive that is better than diamond in some applications when made properly. I dunno - I didn't look too much into it.

HAP I guess is referring to Hitachi's HAP-40 steel (they may have other numbers of "HAP" steel) which from what I quickly read I gather is a powdered metal steel, that may or may not be M4.

According to Hitachi, HAP-40 is a powdered metal HSS steel, with no AISI equivalent, and is not M4 equivalent. M4 equivalent would be Hitach XVC11, or specification name under Japanese Industrial Standards is SKH54.

[Ryan Baker]

The Hitachi powdered-metal high speed steel is supposed to have very long edge retention, particularly with abrasive and hard materials such as the carbon fiber mentioned in the original post. The Lee Valley PMV11 powdered steel has similarities (and differences). David was pointing out that because of the toughness of this steel, you don't want to have to sharpen much of it on normal water stones. He is suggesting something like diamond. The CBN (cubic boron nitride) grinding wheels are very popular among turners for sharpening high speed steel and powdered metal alloy turning tools.

[Stuart Tierney]

The Hitachi powdered-metal high speed steel is supposed to have very long edge retention, particularly with abrasive and hard materials such as the carbon fiber mentioned in the original post. The Lee Valley PMV11 powdered steel has similarities (and differences). David was pointing out that because of the toughness of this steel, you don't want to have to sharpen much of it on normal water stones. He is suggesting something like diamond. The CBN (cubic boron nitride) grinding wheels are very popular among turners for sharpening high speed steel and powdered metal alloy turning tools.

I'd like to make it clear here that Fujikawa specifically recommend that these chisels are not used with a high speed grinder, regardless of what the abrasive in the grinding wheel may be.

I don't completely understand it either, and should ask "why?" which I will as soon as I get a spare moment to do so. It may have something to do with these chisels being aimed at the 'woodworker' rather than 'construction site', and if so, it'd be nice to remove that limitation just in case something happens like dropping one on a concrete floor.

(Although if that happens, I don't like the chances of the floor making it out intact...)

The fact is, I don't know for certain which PM-HSS they're actually using, only that's it's frighteningly hard, stupefyingly tough, it takes a very, very good edge and that most ceramic type waterstones will work, although some need some assistance to work well with the steel and some will not work at all.

About the only similarities with the PMV-11 and the Fujikawa Funmatsu Nezumi is that they're both Powder Metal steels, they're both in the form of chisels and both, as far as I'm aware, are the only PM chisels that are available on the open market.

Stu.

[Mel Fulks]

I think the grinder prohibition is one of those "no white shoes after Labor Day things".

[David Weaver]

I'd like to make it clear here that Fujikawa specifically recommend that these chisels are not used with a high speed grinder

Oops!! (I'd probably still grind them, but treat them like I would old carbon steel chisels).

[Stanley Covington]

About the only similarities with the PMV-11 and the Fujikawa Funmatsu Nezumi is that they're both Powder Metal steels, they're both in the form of chisels and both, as far as I'm aware, are the only PM chisels that are available on the open market. Stu.

Tsunesaburo makes a powered metal steel chisel. I have handled but not used one. A friend tested them and told me he was not overly impressed, but his application was not the same, so they may be perfect for what Mat is looking for, as far as I know.

Stan

[Stuart Tierney]

Tsunesaburo makes a powered metal steel chisel. I have handled but not used one. A friend tested them and told me he was not overly impressed, but his application was not the same, so they may be perfect for what Mat is looking for, as far as I know.

Stan

Really?

I did not know that. Next time I talk to dad Tsunesaburo, I'll ask him.

(If I fail to recognize him one more time, he'll probably make a chisel to stab me in the eye with...)

I don't disagree with not being impressed, not at all. While these things by far the meanest chisels I've ever used, and haven't heard of much that's even on the same planet edge retention wise, I still very much prefer a decent, plain white steel chisel for everyday stuff. Nothing to do with sharp or durability though, I don't know why, but it somehow feels wrong to not stop once in a while and touch up the edge on a chisel you're working with.

But not everyone thinks the same. If we agreed, we'd all be happily using rocks as we'd never have moved out of the caves...

And Dave, you'll find out soon enough.

Stu.

[David Weaver]

White steel, I like that a lot, too. It's almost universally a better version of our vintage chisels, and it still sharpens on anything.

And Dave, you'll find out soon enough.

uh oh!

I have a norton IM 313 tri hone on the way. I'm guessing those stones probably aren't going to do it. Well, the carborundum of the bunch might, but the fine stones will be a little lacking. I'll grind it, along with the koyama sort of HSS chisels I ordered. I'm pretty sure I could grind just about anything that had to be tempered without adversely affecting the hardness.

[Chris Vandiver]

Tsunesaburo makes a powered metal steel chisel. I have handled but not used one. A friend tested them and told me he was not overly impressed, but his application was not the same, so they may be perfect for what Mat is looking for, as far as I know.

Stan

That's very surprising to hear that Tsunesaburo makes chisels.

[Charlie Stanford]

That's very surprising to hear that Tsunesaburo makes chisels.

Only his hairdresser knows for sure.

[Stanley Covington]

I spoke too soon. Sorry. Tsunesaburo makes a powdered metal plane they call the Saketsubo or "Sake Pot." I have held this plane but not used it.

The manufacturer I was thinking of was actually Ioroi. They call it the 集成材用鑿　　ハップ４０SYUSEIZAIYOUNOMI HAPPU40. From the name, it sounds like it is Hitachi's HAP40. I have also played with this chisel but not cut anything with it. Here is a link to the webpage. http://www.ioroi.co.jp/menu1.html

Here is a pic.

set_2.jpg

There is no reason I know of that would prevent powered metal from making a great chisel blade for some applications. Note that I am not recommending Ioroi products. I would be embarrassed to own most of their stuff.

Stan