The Cut Knurling Tool

[Bernd]

After getting my Home Shop Machinist magazine a week ago I finally got to reading some of the articles. On the front page is a new, to me anyway, style of kurling tool. It dosen't use compression, or metal deforming to knurl. It actually cuts.

The article is a two part series. Unfortunatley if you don't get the magazine you won't know what I'm talking about. I can't upload a pic because of copy right. So I guess you'll have to steal a friends copy or buy one.

Glad I never got around to building a knurling tool. Now I'll only have to build one.

Bernd

[CrewCab]

The article is a two part series. Unfortunatley if you don't get the magazine you won't know what I'm talking about. I can't upload a pic because of copy right.

How about a C-o-C version 

CC

[ScottM]

Something like this??

http://www.zeus-tooling.com/produkte/raendelfraeswerkzeug_details.php?gruppenid=16

[Bernd]

You got it Scott. Welcome to the collective. 

CrewCab, follow Scott's link. Much better C-o-C than I could draw. Matter of fact it's picture. 

Bernd

[No1_sonuk]

Couldn't you get a similar effect of you cut a left hand thread over a right hand thread?

[ieezitin]

Now that is a neat tool. I would love to see actual results of it. I knurl a lot. And that surly would be a lot lighter on the machine than the other two methods.

Thanks for sharing that.

All the best.               A coveting Anthony.

[Andrew_D]

Couldn't you get a similar effect of you cut a left hand thread over a right hand thread?

Well, in order to get the diamonds running lengthwise like a knurling tool, wouldn't you need a multi-start thread? Both in Left and Right-hand? Sounds like a lot of work to me...but then again, I haven't had to attempt a multi-start thread yet!!

Of course, there's nothing to say that the knurls couldn't run cross-wise, then it shouldn't be too hard to figure out a pitch that looks nice. Say 10-20 TPI, depending on what you want...Hmmm, on second thought, the knurls still wouldn't look right - they'd be veeeeeery long diamonds, since each diamond would basically wrap all the way around the diameter.

You'd probably still need a multi-start thread, just not as many - depends on diameter.

Now you've got me wondering if I can get out of "kids duty" tonight and escape to the shop for an hour to try this out...

Andrew

[andyf]

Sorry if I'm being stupid, but I can't really visualise how it works - which part of it actually does the cutting?

I have to say that my present knurling tool - a straddle type - seems to work very well. Vey occasionally, it "doubles" and produces a pattern finer than intended, but if that starts to happen I just skim the surface down enough to get rid of the evidence and have another go. The exact diameter of knurled knobs etc isn't usually very important. 

Andy

[No1_sonuk]

Couldn't you get a similar effect of you cut a left hand thread over a right hand thread?

Well, in order to get the diamonds running lengthwise like a knurling tool, wouldn't you need a multi-start thread? Both in Left and Right-hand? Sounds like a lot of work to me...but then again, I haven't had to attempt a multi-start thread yet!!

Yup, probably.  I didn't give it much thought.
Multi-start wouldn't be too bad, but for the fact that it'd need A LOT of starts. 

[Bernd]

Couldn't you get a similar effect of you cut a left hand thread over a right hand thread?

If I remember right the author did mention something akin to that. And it does look like you could do that but it would take two setups to accomplish. With this tool you only need to do it once.

Bernd

[Bernd]

Sorry if I'm being stupid, but I can't really visualise how it works - which part of it actually does the cutting?
Andy

Andy,

I have the picture in front of me and am having difficulty figureing out how it works. I wish I could post a couple of pics but no can do.

Anthony said - I would love to see actual results of it.

Anthony,

The diamonds are as crisp as they are on a fine piece of tooling from the Starret company.

Bernd

[ksouers]

Bernd,
I'm going to have to pick up a copy of that.

Over on HMEM a couple years ago one of the members was talking about this type of tool. I couldn't get any details out of him as he was still working on it. He did post a picture of the results. Very clean and crisp edges, every one of them very well defined.

Almost anything would be an improvement over current practice.

Thanks for mentioning it.

[Bernd]

K,

I tracked down the thread it was in. Check under Photo and Video's "The fire eater fuel tank". Could it be that Mcgyver is Mr. Michael Ward?  

I left a little note asking him that in HMEM. Lets see what happens.  

Bernd

P.S. Just checked. He hasn't been on in over 4 months. So I don't know if I'll get a response.

[ksouers]

Great detective work there, Bernd.

Yes, it was McGyver I was talking to about it. Reading a couple threads of his on (I think) HSM some people referred to him as Michael. Sorry, didn't catch a last name. He's somewhere in Canada. Ontario maybe? I would suspect it's the same guy that wrote the article.

[ieezitin]

Sorry if I'm being stupid, but I can't really visualise how it works - which part of it actually does the cutting?
Andy

Andy.
It looks like to me the knurling wheels are set on an angle of around 30*-40*. With there meeting point set at 90* & 270* on the work piece, the action is ran parallel to the axial center of the lathe.
 
They expand and contract to accommodate the different diameters of the intended job. The formed knurling rollers have the cutting edge printed on the outside of the rollers, the angles correspond to the attack angle and the axial dimension, I am assuming then when pressure is applied x and the saddle driven towards the headstock the tool digs in and the rollers revolve round, again I am assuming the cutting edge at the front of the roller is shallow and gets deeper towards the end of the roller allowing just one pass to complete the knurling process.

It cuts its pattern instead of deformation like the old process. This is a marvelous idea!

Hope this helps Andy.                 All the best. Anthony.

[Jasonb]

They work in much teh same way as woodturning texturing tools, the cutters are free to rotate and are driven round by the workpiece, watch this video and imagine two cutters rather than one to give the left and right spirals, they show a knurl right at the end

Jason

[Bernd]

Jason,

Great find on the vid. That just about explains the way the metal tool works, except for two cutters. The metal knurling tool has the wheels set at 30 degree to the work being knurled. The author also explained that the wheels can be sharpened on the side. Something you can't do with using pressure rollering.

Anthony, Nice job explaining how it works. You very close to how the author explained it.

Bernd

[andyf]

Thanks, Jason. That makes everything clear.

The Zeus commercial version Scott gave a link to looks a pretty expensive piece of kit. And it's Swiss, which always seems to double the number I first thought of.

Bernd, in your first post you said you were going to make one. No doubt you'll show it to us all, and lesser mortals like me will then be able to follow in your footsteps!

Andy

[Jasonb]

Found another company doing them as well

http://www.quick-tools.at/knurling-tools/

J

[No1_sonuk]

I've not actually been able to find prices yet.

[Darren]

I've not actually been able to find prices yet.

Think dark clouds .............

[Bernd]

Bernd, in your first post you said you were going to make one. No doubt you'll show it to us all, and lesser mortals like me will then be able to follow in your footsteps!

Andy

Boy Andy, no pressure here, eh?.    I don't know if you'd want to follow in my footsteps. You might wind up being someplace you don't want to be.

Ya, I'll let you know and post pics, but I think hatis will freeze over first at the speed I go at on project's. 

Bernd

[AdeV]

I don't know if you'd want to follow in my footsteps. You might wind up being someplace you don't want to be.

That reminds me of this old saying:

Before you criticise a man, you should walk a mile in his shoes. That way when you criticise him, you're a mile away - and you have his shoes.

 

[Xldevil]

The Zeus commercial version Scott gave a link to looks a pretty expensive piece of kit. And it's Swiss, which always seems to double the number I first thought of.

Moin.

Actually the brand Zeus is German.
The company is:
Hommel + Keller
Präzisionswerkzeuge GmbH
Brunnenstraße 36
D-78550 Aldingen/Germany

At the bottom of this Austrian company´s page is a short animation how "Rändelfräsen"(knurl-milling,or cutting?) works.

http://www.quick-tools.at/raendelfraeswerkzeuge/technik/vorteile_raendelfraesen.php

Cheers,Ralph

[Bernd]

Thanks for finding that link Ralph.

Ok then gentalmen that concludes "Kurling Class 101". Now you all have your assignment. I want to see these in production by next week. 

Kidding aside. I really want to build one of these. My problem at the moment is which tooling needs to be done first. Every time I start on a piece of tooling another comes along that I need to build and I never complete the one I started.

I need to set some priorities, ya like that's going to happen.  Like I said I think there'll be a freeze over first. 

Bernd