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Supporting => Tooling & Machines => Topic started by: sshire on February 19, 2016, 06:49:36 PM

Title: Lathe Tool Height Setter
Post by: sshire on February 19, 2016, 06:49:36 PM
Lathe Tool Setter

There are probably dozens of solutions to setting the height of a lathe tool. From the “pinch the ruler” technique to the Hardinge Height setter as well as the integrated bubble level devices.

A few years ago, I saw a variation of this tool. I honestly don’t remember where so, I can’t properly credit the designer. Although mine is simplified, It’s very accurate.

Drawings are posted in the Plans area.

None of the dimensions are critical. The .5” and .25” rods are Drill Rod (Silver Steel). The fit of the small rod in the larger rod should be a very close slip fit.

When I use mine, I replace the rounded tip of the dial indicator with a flat tip.

(http://i1126.photobucket.com/albums/l604/sshire/Lathe%20Tool%20Height%20Setter/Lathe%20Height%20Setter-1.jpg) (http://s1126.photobucket.com/user/sshire/media/Lathe%20Tool%20Height%20Setter/Lathe%20Height%20Setter-1.jpg.html)

So, here’s how to use it.

Step one

With the height setting tool in a collet or chuck, set the D.I. to 1/2 of the smaller (removable) rod’s diameter. My rod is .25, so the D.I. is set to +.125.

(http://i1126.photobucket.com/albums/l604/sshire/Lathe%20Tool%20Height%20Setter/Lathe%20Height%20Setter-2.jpg) (http://s1126.photobucket.com/user/sshire/media/Lathe%20Tool%20Height%20Setter/Lathe%20Height%20Setter-2.jpg.html)

Step two

Remove the center rod and place the tool under the D.I. tip.

Adjust the lathe tool’s height until the D.I. reads 0.

(http://i1126.photobucket.com/albums/l604/sshire/Lathe%20Tool%20Height%20Setter/Lathe%20Height%20Setter-3.jpg) (http://s1126.photobucket.com/user/sshire/media/Lathe%20Tool%20Height%20Setter/Lathe%20Height%20Setter-3.jpg.html)

That’s it.


Title: Re: Lathe Tool Height Setter
Post by: CHP on February 19, 2016, 06:59:56 PM
Nice small project :ThumbsUp: :ThumbsUp:

are you using a square to make sure your tool
is perfectly 90 degree with your bead :thinking: :thinking:

I'll make one for sure  ;D
Title: Re: Lathe Tool Height Setter
Post by: sshire on February 19, 2016, 07:04:05 PM
What is the issue if the tool isn't at 90°? I'm not understanding that?
Title: Re: Lathe Tool Height Setter
Post by: CHP on February 19, 2016, 07:34:45 PM
It's only to give you a reference.

If it's slightly in an angle you won't have the same reading :thinking:


Title: Re: Lathe Tool Height Setter
Post by: sshire on February 19, 2016, 07:43:17 PM
If the tool is level, relative to the lathe bed, pivoting the tool to any angle shouldn't change the height of the cutting edge.
Being curious, I set a tool to 0, then checked at various angles by rotating the Aloris tool post. Less than .0005 difference.
Title: Re: Lathe Tool Height Setter
Post by: DICKEYBIRD on February 19, 2016, 07:52:00 PM
Here's the original post by this brilliant old man I talk to every day. :old: :ROFL:  Probably not the 1st guy to do it this way or the last. :cheers:

http://bbs.homeshopmachinist.net/threads/60113-Yet-another-lathe-tool-center-setting-gauge?highlight=TOOL+HEIGHT

I do check with a square each time to ensure accuracy & consistency.
Title: Re: Lathe Tool Height Setter
Post by: CHP on February 19, 2016, 07:58:17 PM
If the tool is level, relative to the lathe bed,

yes this is what I ment by using a square to set the indicator 90 with the bead :cheers:
Title: Re: Lathe Tool Height Setter
Post by: sshire on February 19, 2016, 08:19:12 PM
Of course. I thought you meant squaring the cutting tool.
I do use a square against the frame of the setting tool.
Sorry for my confusion.
I believe that is the original post  that I saw. I've searched and couldn't find it.
Thank you
Title: Re: Lathe Tool Height Setter
Post by: philjoe5 on February 19, 2016, 08:28:33 PM
Nice, I'm going to make one. :ThumbsUp:

Cheers,
Phil

Title: Re: Lathe Tool Height Setter
Post by: DICKEYBIRD on February 19, 2016, 09:05:17 PM
Another cool thing I discovered is that after you've set the tool height , you can rotate the gauge 90 deg away from you, re-square it and jog the tool in or out until it's at zero again & set the offset in Mach3's tool table.  (Or whichever CNC lathe controller du joir you're using) .  Come to think of it, if you've got DRO's on a manual lathe it'd be worthwhile setting up a tool table using the same method.

Of course, that's just a repeatable starting point for all your different tools.  The type of tool, material, speed/feed etc. makes a difference in the final position of the tool tip needed to end up with a precise part diameter.  I now have 16 different QC tool holders dialed-in including a couple drill holders & a QC X-axis live drill for drilling holes from the side.  (I'm working on a QC mounted TPG right now that will need to be dialed-in too.)

That gauge tool sure makes the the setup a lot easier!
Title: Re: Lathe Tool Height Setter
Post by: Hugh Currin on February 20, 2016, 12:13:22 AM
Nice tool for setting tool height. Much more accurate than the eye I've always used. After reading this I think I'll make one up pretty soon.

Another cool thing I discovered is that after you've set the tool height , you can rotate the gauge 90 deg away from you, re-square it and jog the tool in or out until it's at zero again & set the offset in Mach3's tool table.  (Or whichever CNC lathe controller du joir you're using).
Briliant. Now I'll have to make one up real soon.

Stan & Dickeybird, thanks.

Hugh
Title: Re: Lathe Tool Height Setter
Post by: phrodo on February 20, 2016, 10:53:27 AM
Hi,

Forgive me if I'm missing something here, but don't the two pictures show a delta of 0.1125 not 0.125?

John
Title: Re: Lathe Tool Height Setter
Post by: pgp001 on February 20, 2016, 11:41:49 AM
Well spotted, you are right. One turn plus 0.0125 is not 1/8", it should be reading 0.025
The principle works though, he probably just had a "Blonde" moment setting it up for the photo.

Phil
Title: Re: Lathe Tool Height Setter
Post by: sshire on February 20, 2016, 01:18:54 PM
Correct. It was a quick setup for the photo shoot.
Good catch, though.
Title: Re: Lathe Tool Height Setter
Post by: DICKEYBIRD on February 20, 2016, 03:14:44 PM
Now that the pics are being talked about; is it just the wonky vision caused by my progressive lenses or does the test rod lean upwards?  I hope it's just me. :insane:
Title: Re: Lathe Tool Height Setter
Post by: pgp001 on February 20, 2016, 03:45:37 PM
Its just barrel distortion on the camera lens. It can often happen on close up shots.
Look at how the straight lines in the background curve the opposite way in the top of the photo.

Phil
Title: Re: Lathe Tool Height Setter
Post by: sshire on February 20, 2016, 04:38:50 PM
It's you.  :lolb: The rod is dead nuts parallel to the bed. If not, my super precise, genuine Bison, made by Polish craftsmen, Set-Tru 5C collet chuck is at an angle. Highly unlikely.
It's actually a lens aberration which, if it was necessary, I could correct in Lightroom as I've created aberration formulae for all of my lenses.
Title: Re: Lathe Tool Height Setter
Post by: DICKEYBIRD on February 20, 2016, 06:20:20 PM
It's you.
Whew!  Thanks.
Title: Re: Lathe Tool Height Setter
Post by: Mosey on February 20, 2016, 08:49:23 PM
That is a great tool and I will likely make one too.

I presently use a simpler one that I made. It is a block with a vee in one side and a corresponding ledge on the other, both exactly aligned to a center. The exactness is a result of your work to aligned them. There is a small bubble level in the top. When the bubble is leveled, the vee is held against the cylindrical work piece in the lathe, and the ledge is sitting on the tool tip, then the tool tip is exactly on the lathe center. Easy to make, accurate, no adjustments required. To correct any discrepancies, simply screw the tool holder up or down and watch the bubble center itself.
(The rag is to hold it in place while I photo)

Mosey
Title: Re: Lathe Tool Height Setter
Post by: sshire on February 21, 2016, 12:34:12 AM
That's very nice. How about replacing the level with one of those digital levels?
Title: Re: Lathe Tool Height Setter
Post by: mklotz on February 21, 2016, 12:49:50 AM
Stan's device allows one to set the tool precisely above or below center height, the former to account for tool deformation under load.  Doing that precisely with a level would be a lot more difficult.

I have a commercial version of Mosey's device.  Used it once; now it's a toolbox decoration.
Title: Re: Lathe Tool Height Setter
Post by: sshire on February 21, 2016, 01:29:51 AM
Marv
I bought one also. In a drawer. Used a few times.
Title: Re: Lathe Tool Height Setter
Post by: kvom on February 21, 2016, 02:01:28 AM
My own technique is to face some stock and adjust until there's no center nib left.
Title: Re: Lathe Tool Height Setter
Post by: V 45 on February 21, 2016, 02:19:16 AM
I had made this simple tool for setting height with lathe tools. Works very well but probably not as accurate as some with indicators. I use it all the time...
(http://i851.photobucket.com/albums/ab77/rmist04/th_Height20setter_zpsu9aztgfg.jpg) (http://s851.photobucket.com/user/rmist04/media/Height20setter_zpsu9aztgfg.jpg.html)
Title: Re: Lathe Tool Height Setter
Post by: Pete49 on February 21, 2016, 02:30:11 AM
As my main lathe is 8x22 I used a simple method from the workshop practise series by Harold Hall. Basically a cylinder is turned with a flat base and top that sits on the cross slide and the tool tip sits under the top. Looks like 'I' with the centre of the lathe height  being the bottom of the top. Its made for the specific lathe and is simple and fast. I made mine from a scrap piece of 1.5" round rod I had and reduced the centre thickness to 1". I'll get a pic next time I go to the shed.
Pete
Title: Re: Lathe Tool Height Setter
Post by: Doc on February 21, 2016, 05:37:05 AM
I've used this technique for many years and if careful will get you right on every time.
https://www.youtube.com/watch?v=vpCu56O8AJ0
Title: Re: Lathe Tool Height Setter
Post by: sshire on February 21, 2016, 12:52:07 PM
And...these techniques all work and are "close 'enuf"

The ruler method, as Tom Lipton says, is "eyeball-centric"


Pete
Yours sounds like a variant of the Hardinge L2-A.

http://aafradio.org/garajmahal/Hardinge_L-2A_Tool_Setting_Gauge.html

Marv
Note "garajmahal"


Title: Re: Lathe Tool Height Setter
Post by: pgp001 on February 21, 2016, 02:40:19 PM
I have used a home made version of the Hardinge tool for many years, in fact until today I did not even know it was a Hardinge tool. I think my dad showed me how to make one when I was a teenager.

The good thing about it is that you can use it for tools in the front toolpost as normal, but it also works just as effectively for upside down tools in the rear toolpost, ie parting tools.

Phil
Title: Re: Lathe Tool Height Setter
Post by: mklotz on February 21, 2016, 03:22:06 PM
The (minor) problem with the ruler method is that it doesn't work very well on polygonal, or even heavily knurled, workpieces.

I use a method that is a variant of Pete's method.  I relieved the bottom of a small block of steel so it sits flat on the top of the compound.  Then I machined this block to a height such that its top surface is exactly at center height.  Push it up against the lathe tool and drag your thumbnail from tool to block or vv.  Your fingers are incredibly sensitive; you'll feel the slightest difference in height.
Title: Re: Lathe Tool Height Setter
Post by: Mosey on February 21, 2016, 05:40:53 PM
There are many good ideas here for me to learn from. I suspect that in a production shop you face off an end and then raise the tool until the tit goes away.
Mosey   :facepalm:
Title: Re: Lathe Tool Height Setter
Post by: mklotz on February 21, 2016, 05:47:11 PM
There are many good ideas here for me to learn from. I suspect that in a production shop you face off an end and then raise the tool until the tit goes away.

An iterative procedure like that probably takes too much time to be used in a production shop.  Also, it doesn't work well on tubing or parts with a center hole.
Title: Re: Lathe Tool Height Setter
Post by: Jo on February 21, 2016, 05:49:17 PM
In a production shop each tool has its own tool holder, once set you don't have to do it again  :ShakeHead:

Jo
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