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View Full Version : How to engrave graduations on tailstock spindle?



brian Rupnow
08-16-2009, 03:10 PM
My cheap Chinese lathe has no graduations on the spindle. This is not the biggest problem in my life, but I would like to put some graduations on there (as in 1/16's of an inch, maybe even 1/32s). It is easy to remove from the tailstock, so I am assuming I could remove it, set it up in my milling vice, and cut my own graduations. ---How would I do that??---Slitting saw with a real thin blade?
http://i307.photobucket.com/albums/nn294/BrianRupnow/TAILSTOCKSPINDLE002.jpg

hornluv
08-16-2009, 03:13 PM
Why not just chuck it in the lathe itself and then hand turn it to scribe the graduations? Set up an indicator so you can advance it the correct amount. Scribe the first line, set the indicator at 0 and then off you go.

brian Rupnow
08-16-2009, 03:20 PM
Why not just chuck it in the lathe itself and then hand turn it to scribe the graduations? Set up an indicator so you can advance it the correct amount. Scribe the first line, set the indicator at 0 and then off you go.

That might work--I assume biggest problem would be stopping and starting at the same angle each time.---Nope, won't work. The thru hole in my chuck is too small to let the spindle slide thru, and I can't use a bearing center in my tailstock to support the outboard end because my tailstock has no spindle now.

John Stevenson
08-16-2009, 03:26 PM
Make some stop bars that go on the bed and contact the chuck jaws.
Start from a scribed line and using a vee tool like a screw cutting tool you will be able to feel the start. You then need to get some order as to which stop bar you use.

A bit like playing the piano, you need notes to work from :D
Different colours for each length and a bit of tape or paint on the stop bars.

Plink plonk Brian's coming :D :rolleyes:

[edit] yes you can use the tailstock. Before you strip it down make a double tapered slug like a plumb bob use this between the barrel and the tailstock bore .

.

winchman
08-16-2009, 03:31 PM
Use a vibrating engraving tool placed against the end of the tailstock body. Put an indicator in the chuck to advance the ram for each mark.

I'd try to get the handle on the wheel at the top or bottom for the first mark, so it'll be easy to count turns when you want to go fast. That'll only work if the screw has an 8-pitch thread, though.

Roger

rkepler
08-16-2009, 03:50 PM
I made an MT3 quill for my tailstock, and did the the engraving using a V tool in a boring bar mounted in the spindle of my mill, the quill in the vise sideways. That way you can control the engraving depth with the Y feed and the position with the X. I used the quill stop for the length of the markings. Here's a shot of the end result:

http://www.kepler-eng.com/images/mt3_a.jpg

(And yeah, I know MT3 is a bit much for that quill, but once in a while I like to simply drill out and hole and you can sneak up on it so the quill doesn't see all the torque at one time).

lugnut
08-16-2009, 04:14 PM
Here is my inlay of a piece of machinists rule in my tailstock. It has worked great.
http://img.photobucket.com/albums/v671/lugnut/P4070001b.jpg
Mel

brian Rupnow
08-16-2009, 04:25 PM
Here is my inlay of a piece of machinists rule in my tailstock. It has worked great.
http://img.photobucket.com/albums/v671/lugnut/P4070001b.jpg
Mel

Now that I really like!!!

Peter.
08-16-2009, 05:15 PM
Figure out the pitch of the tailstock screw and advance the tailstock to your desired increments at say half a turn/ 1 turn and scribe a line on the quill against the end of the housing each advancement.

crancshafter
08-16-2009, 05:23 PM
My cheap Chinese lathe has no graduations on the spindle. This is not the biggest problem in my life, but I would like to put some graduations on there (as in 1/16's of an inch, maybe even 1/32s). It is easy to remove from the tailstock, so I am assuming I could remove it, set it up in my milling vice, and cut my own graduations. ---How would I do that??---Slitting saw with a real thin blade?
http://i307.photobucket.com/albums/nn294/BrianRupnow/TAILSTOCKSPINDLE002.jpg

Hi Brian.
Why not do it this way.:)
http://bbs.homeshopmachinist.net/showthread.php?t=28169&highlight=digital+caliper+tailstock

Regards CS

brian Rupnow
08-16-2009, 05:30 PM
Hi Brian.
Why not do it this way.:)
http://bbs.homeshopmachinist.net/showthread.php?t=28169&highlight=digital+caliper+tailstock

Regards CS

Thats a great idea, but my tailstock spindle had VERY minimal travel---like about 1.375"----I can't afford the room it would take to put a clamp around the spindle nose.

John Stevenson
08-16-2009, 05:40 PM
So loose 3/16" off the front of the overhang, just enough for the clamp and you have lost nothing.

Or if you don't want to do that drill and file a slot in the casting enough to take a bolt to hold the caliper on.
.

topct
08-16-2009, 05:54 PM
What is the problem with using the graduations on the feed wheel?

brian Rupnow
08-17-2009, 10:00 AM
I used the method suggested by Lugnut---Milled a slot in the top of the spindle just wide and deep enough to accept a small machinists scale which I glued into place with Loctite. Works great!! Thanks Lugnut.---Brian
http://i307.photobucket.com/albums/nn294/BrianRupnow/grads-1008.jpg

Kd0afk
04-16-2013, 01:14 PM
I have a dremel holder for my qctp and I plan on chucking my tailstock quill in the lathe and cutting different depth grooves for the major and minor markings. Should work. Then stamp the 1" marks. I think for the register mark a piece of steel with a magnet to attach to the tailstock.

Paul Alciatore
04-16-2013, 01:45 PM
I would NOT cut any circumferential markings in the tail stock spindle. Each such cut mark is a stress riser that weakens the spindle. Perhaps I am being excessive, but that is my opinion on it.

Brian's scale in a longitudinal slot is perhaps better as the corners of the slot are parallel to the length of the spindle instead of going crosswise.

Personally, I would use a chemical staining process to do this. You can buy etch pens for this purpose and devise a setup to use it in a manner similar to using a cutting tool.

Or just mount an external scale.

drmico60
04-16-2013, 02:05 PM
I took a different appraoch when I modifed my tailstock in that I added a separate rule at the top of the tailstock housing and this slides in and out with the quill. This has the added advantage in that it is easy to add a movable index allowing the scale to be zeroed. More details are here:
http://mikesworkshop.weebly.com/tailstock-modifications.html
Mike

Kd0afk
04-16-2013, 02:19 PM
Not running the lathe when i make the marks. locking the spindle and cutting the marks with the cross slide. I won't turn the grooves into the thing.

Kd0afk
04-16-2013, 08:46 PM
One of the problems I have is that the space between the end of the barrel and the end of the tailstock is very small when the barrel is fully retracted. I can't fit a bracket on the end. I do like the idea of machining a slot in the barrel for a small rule. I'm guessing the slot won't weaken the thing. I don't own a mill but I think I can rig something. I've found that the repeatability of these digital calipers is iffy at best.

darryl
04-16-2013, 09:18 PM
You could just clamp it into a slot on the mill, then mount a cutter in the mill spindle. The spindle is held in position, not rotating, and the Y axis cranks the tailstock spindle past the cutter. The X axis cranks out the spacings. Because the spindle is round, you'd be scratching across the top of the curve. The deeper you go, the longer the scratched line. Use that as a guide to get your longer and shorter markings scratched in. The starting and ending points will line up pretty well and it should look good.

I'd be highly tempted to go a step further and fill the scratched marks with black paint or a dark epoxy. Once that's cured or dried, the excess is scraped off, leaving a nicely visible result.