A method of tail stock alignment that works pretty well for me.
#1
When I got my new 11x26 lathe in a couple of weeks ago I knew the tail stock was probably going to be out of alignment horizontally. I'm not too concerned about the vertical, yet.
I remembered this video,
http://www.youtube.com/watch?v=6Tkbt6VJpIM
and decided I could do something similar that should get me pretty close.

This method does require that you can securely mount a dial indicator on your tool holder at centerline.

From a previous project I had made a small HSS boring bar. It's tiny and only really good for boring a taper a small distance, but since it mounts as a boring bar and not in the tail stock it will always cuts true to the lathe centerline. Anyway, I had a chunk of .750" drill rod about 14" long. I first mounted in the 4 jaw and got it running true to within .001". I then center drilled it. Then set my compound to 30 degrees and mounted my little boring bar in it's holder. I then took a black marker and colored the center drilled hole. Using the compound I then shaved out just the minimum. Sure enough the centered drill hole was just barely out of center. Another small pass and the tapered bore was complete. I then removed the bar and flipped it end for end.
On the other end I did the same thing but I also turned the outside diameter down just a bit, just enough to make sure I'd cut all the way around + a bit. The exact amount you take off isn't important just as long as it's easy to identify which end has been turned down. I would not recommend turning down both ends.

Now to use the alignment bar.

Set dead centers in the head and tail stocks. Mount the bar between the centers with the turned outside diameter end at the head stock end. Mount the dial indicator on your tool holder and indicate on the turned portion of the bar with a moderate amount of pressure. I like to just set the dial indicator face to a comfortable position for Zero,then wind it in to Zero. Now unmount the bar and flip it end for end and tighten back in between centers. Move the carriage to the tail stock end and indicate on the turned part again. The difference between Zero and what it now reads is how much the tail stock is out of alignment. Adjust accordingly. I had to flip ends a couple of times while adjusting the tail stock before I got both ends to read Zero consistently. I should mention in case it's not obvious, Don't move the indicators position with the cross slide or the compound once you've set Zero.

Out of the box my tail stock was about .030" out. I adjusted the tail stock end so both ends read zero. So far bars turned between centers are .0007" tapered in diameter from tail stock end to just shy of the lathe dog on the head stock end. This seems to be pretty consistent.
If it's crazy but it works, it's not crazy.
Reply
Thanks given by:
#2
Sounds like a 6799 but alas, my tailstock isn't adjustable.

Tom
[Image: TomsTechLogo-Profile.png]
Reply
Thanks given by:
#3
My tailstock is adjustable but I don't have a tapered spindle bore. Well I do - it starts off a little more than 3" and tapers down to al little less than 3" at the outer end. I suppose I could mount a chunk of steel in the chuck and turn it to a 60* point.
Hunting American dentists since 2015.
Reply
Thanks given by:
#4
(07-29-2013, 07:16 AM)Mayhem Wrote: My tailstock is adjustable but I don't have a tapered spindle bore. Well I do - it starts off a little more than 3" and tapers down to al little less than 3" at the outer end. I suppose I could mount a chunk of steel in the chuck and turn it to a 60* point.

That's what Keith Fenner does on his big lathe when he's turning between centers. I'd do the same if I had to use a chain hoist to mount and unmount my 4 jaw chuck. Sweat

Actually I do that anyways most of the time because most of my between centers turning is less than 1.25" diameter. And it's just easier to chuck a piece of bar and turn it to a 60* point than to unmount the chuck, mount the dead center and mount the face plate. Works great. I've go one piece of bar I use just for this. Chuck it up, turn it to true it up at 60* and off I go.
If it's crazy but it works, it's not crazy.
Reply
Thanks given by:
#5
(07-29-2013, 11:53 AM)marfaguy Wrote:
(07-29-2013, 07:16 AM)Mayhem Wrote: My tailstock is adjustable but I don't have a tapered spindle bore. Well I do - it starts off a little more than 3" and tapers down to al little less than 3" at the outer end. I suppose I could mount a chunk of steel in the chuck and turn it to a 60* point.

That's what Keith Fenner does on his big lathe when he's turning between centers. I'd do the same if I had to use a chain hoist to mount and unmount my 4 jaw chuck. Sweat

Actually I do that anyways most of the time because most of my between centers turning is less than 1.25" diameter. And it's just easier to chuck a piece of bar and turn it to a 60* point than to unmount the chuck, mount the dead center and mount the face plate. Works great. I've go one piece of bar I use just for this. Chuck it up, turn it to true it up at 60* and off I go.

+1

I also do that whenever I need to turn between centers.

Ed
Reply
Thanks given by:
#6
I suppose I'd better make a dog now as well.
Hunting American dentists since 2015.
Reply
Thanks given by:
#7
(07-30-2013, 05:52 AM)Mayhem Wrote: I suppose I'd better make a dog now as well.

A good tip I read on another board was to use an electrical grounding clamp, like this.
   

Work great for diameters up to 1.5" (38mm or so). A .25" (about 6mm) diameter piece works for the drive pin.
Most home improvement places have them. Well at least in the US anyway, I don't know if such things exist in the wilds of Australia though.
Rotfl
If it's crazy but it works, it's not crazy.
Reply
Thanks given by:




Users browsing this thread: 1 Guest(s)