Newbie Needs Help

[lkorn]

I've been lurking here for awhile and have enjoyed all the post and learned far more thanI could have taught myself is a year of turning.
I have turned about a dozen pens so far and have enjoyed every one, including the mistakes. My problem; I am turning on an old "Craftsman" lathe that uses a 3" pipe for the bed. I can't seem to get the tailstock in the same place twice in succession. I can force it into alignment before tightening it, but there is no repeatability. Short of buying a new lathe (atleast for awhile) does anyone have any ideas as to how to compensate for this?

Thanks,

Larry

 

[Fred in NC]

Larry, I had the same problem with my first lathe. I used some Disney Solutions* so I could use it for pens. I am not familiar with your lathe.

First of all, what is the ram travel of your tailstock?
What kind of Morse taper does it have?
What is the taper of the headstock?
What kind of mandrel are you using?

Please let me know, and I will try to help.

*Mickey Mouse

 

[Doghouse]

I think I understand what you are saying...

How about mounting a board behind the lathe that you could register the tail stock up to every time. That way you would know your centers matched up.

If I am off base, give me a little more information or a picture and we can come up with something. A lot of creative people here.

 

[lkorn]

Both headstock and tailstock use #1 MT. Ram travel is about 2.5-3 inches. I'm using a mandrel purchased from Woodcraft. I don't really "SEEM" to have a problem with penmaking, but I don't remove the tailstock until I'm done.

To elaborate a little further, the tailstock rides on a 3" round pipe being used as the lathe bed. When not locked in place, it is free to rotate slightly around the pipe (about 1/2" rotational travel. I have to force it into alignment before moving the rream into the mandrel. Therefore, no repeatability.

Thanks for your help,

Originally posted by Fred in NC
<br />Larry, I had the same problem with my first lathe. I used some Disney Solutions* so I could use it for pens. I am not familiar with your lathe.

First of all, what is the ram travel of your tailstock?
What kind of Morse taper does it have?
What is the taper of the headstock?
What kind of mandrel are you using?

Please let me know, and I will try to help.

*Mickey Mouse

 

[lkorn]

What kind of board? I don't understand how this would work....

Originally posted by Doghouse
<br />I think I understand what you are saying...

How about mounting a board behind the lathe that you could register the tail stock up to every time. That way you would know your centers matched up.

If I am off base, give me a little more information or a picture and we can come up with something. A lot of creative people here.

 

[Fred in NC]

OK, Larry, thanks for the info.

What I am thinking of is that you might be able to accurately center your tailstock, and then leave it locked in position, and back up the ram all the way to remove parts or change the mandrel.

This will work a lot better with a machinist live center, which has a 60 deg taper with no ring around it. If you don't have one, maybe it will pay to get one. The are $12 for a good one from several suppliers.

Put the mandrel in the headstock, and seat it all the way in (by hand). Bring your tailstock and align it by hand the way you have been doing. Tighten the ram just a little to completely seat the Morse in. That is so it will be accurately centered.

Now, loosen the tailstock, and move it away about 3". Move the ram out as far as it will go, and back up 1/4". It will be extended out of the tailstock almost all the way out. Bring the tailstock (with extended ram) to meet the end of the mandrel, and center it on the mandrel's end. Now, lock the tailstock as tight as you can (but don't strip the threads, hehe!).

Back up the ram all the way. See if you can remove the mandrel without moving the tailstock.

Let me know how this works.

 

[Paul in OKC]

Is there a key stock that runs the length of the 'pipe'? Maybe you could find someone to drill and tap a set screw into the tailstock housing to hit the side of that, and adjust it to get your alignment. As far as a board, if you cut a 2x4 to fit between the back of your bench or wall to the back side of the tail stock, you could slide the tail stock up and set it against the board and lock down. Just some thoughts.

 

[lkorn]

Thanks Fred,

I have a live center, I will try to see if I can add or remove components by moving the ram only. Removing the mandrel is a PITA, I have to open the drive compartment IOT access the back side of the headstock through hole.

Originally posted by Fred in NC
<br />OK, Larry, thanks for the info.

What I am thinking of is that you might be able to accurately center your tailstock, and then leave it locked in position, and back up the ram all the way to remove parts or change the mandrel.

This will work a lot better with a machinist live center, which has a 60 deg taper with no ring around it. If you don't have one, maybe it will pay to get one. The are $12 for a good one from several suppliers.

Put the mandrel in the headstock, and seat it all the way in (by hand). Bring your tailstock and align it by hand the way you have been doing. Tighten the ram just a little to completely seat the Morse in. That is so it will be accurately centered.

Now, loosen the tailstock, and move it away about 3". Move the ram out as far as it will go, and back up 1/4". It will be extended out of the tailstock almost all the way out. Bring the tailstock (with extended ram) to meet the end of the mandrel, and center it on the mandrel's end. Now, lock the tailstock as tight as you can (but don't strip the threads, hehe!).

Back up the ram all the way. See if you can remove the mandrel without moving the tailstock.

Let me know how this works.

 

[lkorn]

Paul, good ideas! The board won't work as my lathe is resting on saw horses and would have to much "give" in the mountg. (I know that this isn't ideal, but ...) Taping for a setscrew is far more practical for my setup, and may work. I'm only concerned that it will lock the tailstock in place requiring yet another screw to move for adjusting. Time will tell.

Originally posted by Paul in OKC
<br />Is there a key stock that runs the length of the 'pipe'? Maybe you could find someone to drill and tap a set screw into the tailstock housing to hit the side of that, and adjust it to get your alignment. As far as a board, if you cut a 2x4 to fit between the back of your bench or wall to the back side of the tail stock, you could slide the tail stock up and set it against the board and lock down. Just some thoughts.

 

[Fred in NC]

Larry, any chance you can drill a hole in the cover to line up with the spindle? That will make using a knockout bar a lot easier!

 

[Paul in OKC]

Originally posted by lkorn
<br />Paul, good ideas! The board won't work as my lathe is resting on saw horses and would have to much "give" in the mountg. (I know that this isn't ideal, but ...) Taping for a setscrew is far more practical for my setup, and may work. I'm only concerned that it will lock the tailstock in place requiring yet another screw to move for adjusting. Time will tell.

YOu wouldn't have to tighten the set screw, just adjust it until the tail stock lines up. You should have enough play to allow for that.

 

[lkorn]

Actually, I was lying in bed last night thinking about doing just that!

Thanks.

Originally posted by Fred in NC
<br />Larry, any chance you can drill a hole in the cover to line up with the spindle? That will make using a knockout bar a lot easier!