Tangential tooling/holder

Topics include, Machine Tools & Tooling, Precision Measuring, Materials and their Properties, Electrical discussions related to machine tools, setups, fixtures and jigs and other general discussion related to amateur machining.

Moderators: GlennW, Harold_V

Wayne Shaw
Posts: 41
Joined: Thu Feb 28, 2008 5:55 pm
Location: VA

Tangential tooling/holder

Post by Wayne Shaw »

I've read a bunch on this type of tool and holder through searches. It seems like a reasonable way to go, given the simplicity of sharpening. Before I order one of these things, my thick skull needs some penetrating with a couple answers.

They use square tool bits, they are sharpened on quite an angle, 30 degrees I think. So the question is, with that angle of grind, and the tool mounted with the 12 degree rake, will the cutting surface of the tool actually be less than the square tool? Meaning, will it have clearance/relief on both sides if cutting to a shoulder?

And along the same lines, could a bit be "simply" ground so it could be used in regular 60 degree threading?

Thanks.
User avatar
GlennW
Posts: 7284
Joined: Sun Apr 15, 2007 9:23 am
Location: Florida

Re: Tangential tooling/holder

Post by GlennW »

If you take a square tool bit, stand it up vertically, and cut it on an angle from corner to corner, you end up with a 80° diamond shape if looking down on it, if the angle is then aligned with a horizontal plane.

Is the cutting surface of the one on the left still square when the square tool bit is cut on an angle and tipped so that the top surface is horizontal?

Image

One must have less than 90° in order to use the same tool for both functions unless different corners of the tool are the cutting edges. In this case, the cutting tool is assumed to be a 90° square HSS blank.

If you then properly oriented it in a holder, it WILL turn and face using a square tool bit.

Image
Glenn

Operating machines is perfectly safe......until you forget how dangerous it really is!
User avatar
GlennW
Posts: 7284
Joined: Sun Apr 15, 2007 9:23 am
Location: Florida

Re: Tangential tooling/holder

Post by GlennW »

I made one one afternoon out of curiosity just to play with after following a discussion on them.

Might have taken an hour to make from 4140 Pre-Hard Bar. 5/8 shank.

Image

Image

Image

I was not real impressed with the chip control, or lack of, but it was OK on aluminum for light cuts.

Never really used it again.

I will add that I use a six horsepower lathe and mainly indexable tooling, with the exception of HSS form tools, so removing metal has never been a real problem. Using a smaller bench lathe may be where the advantage is with this type of tooling.

Just my $.02
Glenn

Operating machines is perfectly safe......until you forget how dangerous it really is!
Lew Hartswick
Posts: 775
Joined: Sat Jan 04, 2003 10:45 am
Location: Albuquerque NM

Re: Tangential tooling/holder

Post by Lew Hartswick »

I did a threading one back a few years ago it works BUT you can't get close to a shoulder with
it.
link to a bunch of pix :

http://home.earthlink.net/~lhartswick/Diamond threading tool/

HUMMMM! for some reason the last part of that is not included in the link.
I'll try to fix it.
Even on second try it wont put the - threading tool - in the link Anyone know why it doesn't?
I cut and pasted the link.

http://home.earthlink.net/~lhartswick/Diamond threading tool
I typed this in now to check it
Still won't complete the entire link. :-(
just go to the first part and look for the rest.
...lew...
EdK
Posts: 688
Joined: Tue Apr 13, 2010 6:20 am
Location: Minnesota

Re: Tangential tooling/holder

Post by EdK »

lew,

It looks like it doesn't like the spaces in the URL.

http://home.earthlink.net/~lhartswick/D ... ng%20tool/

Ed
Vectrax 14x40 lathe, Enco RF-45 clone mill, MillerMatic 180 MIG.
Lew Hartswick
Posts: 775
Joined: Sat Jan 04, 2003 10:45 am
Location: Albuquerque NM

Re: Tangential tooling/holder

Post by Lew Hartswick »

EdK wrote:lew,

It looks like it doesn't like the spaces in the URL.

http://home.earthlink.net/~lhartswick/D ... ng%20tool/

Ed
Thanks I wonder why the other ones work with a space. I must have typed that entry
somehow different from the others.
Anyway it works the way you posted it. :-)
...lew...
Russ Hanscom
Posts: 1955
Joined: Wed Mar 15, 2006 11:10 pm
Location: Farmington, NM

Re: Tangential tooling/holder

Post by Russ Hanscom »

Glenn,

Nice large scale example with the wood.
awake
Posts: 70
Joined: Fri Jan 29, 2010 5:07 pm
Location: Angier, NC

Re: Tangential tooling/holder

Post by awake »

Here is my version of the tangential tool holder:

Image

Image

The pictures are not that great, and as you will see in the second picture, I got the dovetail on the holder a little over-sized -- but nonetheless, the tool works extremely well. This is the one tool I use 90% of the time.
Wayne Shaw
Posts: 41
Joined: Thu Feb 28, 2008 5:55 pm
Location: VA

Re: Tangential tooling/holder

Post by Wayne Shaw »

OK, thanks for the replies. It seems like some people really like the tool held this way and it's performance and some are not crazy about it. I guess that goes for most anything.

The idea of threading with one, and threading to a shoulder seems to be in the position of the tool. Since only the leading edge of the tool cuts while threading, it seems like the tool would have to be reduced in size and the back half ground away. I only need to get as close as about .075' to a shoulder.

I'm still thinking hard about getting one.
User avatar
Harold_V
Posts: 20232
Joined: Fri Dec 20, 2002 11:02 pm
Location: Onalaska, WA USA

Re: Tangential tooling/holder

Post by Harold_V »

Wayne Shaw wrote:I'm still thinking hard about getting one.
If this helps--------I worked in the machining trade for 26 years, non-stop. In all those years, I never once saw a tool like that used. They're not new----they're just not practical. Further, there's nothing particular about them aside from the angle in which the tool is presented to the work. You can duplicate the geometry with a conventional tool easily, plus you have far greater latitude in tailoring the tool to a specific application.

Said another way----take note that Glenn abandoned the use of the one he made. If nothing else, they're too restrictive in their application, and as a bonus, if you can't easily fashion a chip breaker on a cutting tool, it likely is best not used. Once you've received a dozen (or more) stitches because of long stringy chips, that may make more sense.

Harold
Wise people talk because they have something to say. Fools talk because they have to say something.
awake
Posts: 70
Joined: Fri Jan 29, 2010 5:07 pm
Location: Angier, NC

Re: Tangential tooling/holder

Post by awake »

Harold, I hesitate to disagree, but ... I respectfully disagree.

There are many things suitable for home shop use that you will rarely or never find in a commercial shop ... starting with HSS tooling!

Yes, you could grind the shape into a conventional tool, but I guarantee that I can grind a new bit for this tool holder a whole lot faster -- and when it comes time to regrind to touch it up, I'll definitely be way faster! :) And yes, I do grind other tool bits -- many of them, for various specialized needs.

Though the picture above shows a long continuous string, I almost never actually get that kind of chip off this tool. Most of the time I get nice 6's and 9's, or else a tight spiral that breaks off as soon as it gets 1/4 inch long or so.

I certainly respect Glenn's personal experience, but mine differs -- as I said, I use mine 90% of the time. Most of the other 10% is threading -- I don't use this tool for threading, nor do I have any desire to do so. The extra effort to grind it just so would eliminate the whole point of this tool for me.
User avatar
Harold_V
Posts: 20232
Joined: Fri Dec 20, 2002 11:02 pm
Location: Onalaska, WA USA

Re: Tangential tooling/holder

Post by Harold_V »

awake wrote:Harold, I hesitate to disagree, but ... I respectfully disagree.

There are many things suitable for home shop use that you will rarely or never find in a commercial shop ... starting with HSS tooling!
Considering your comments, I agree (although prior to CNC operations, HSS was very much a part of commercial operations, and still is where multi-toothed cutters are concerned (side cutters, for example). I am jaded in that while I operated a humble shop, it still was expected to perform in keeping with industry standards. I tend to avoid tools that can not be applied as one might be expected to. Truth is, every tool has a place, including carbon steel tools.

The one place where I expect a tangential tool would not compete well is in taking heavy (roughing) cuts. Unless some provision was made for the exceedingly high pressure pushing downwards, I expect you might experience movement of the tool (not an acceptable thing to experience). If you can take .250" off per side with a .015" feed, I might view that idea differently. Can you? That would really sort it in my mind. In spite of not working for gain now, when I operate my lathe, if there's material to be removed, it's done as quickly as it can be done on my machine----never would I consider being hampered by tool design.

Harold
Wise people talk because they have something to say. Fools talk because they have to say something.
Post Reply