Help lining up headstock with tailstock

[paynerd]

I understand the concept of how to do it but my question is this.

EVERYTHING I have to do this with is MT3 tapered. I don’t want to put something tapered in my chuck. Is there a part I need to get so I can put something tapered in my chuck? Or is there a live center that’s straight and not tapered for the chuck? What am I missing here?

 

[RJSakowski]

Put a piece of round stock in the chuck and turn it to a point. It will be true to the spindle axis.

 

[ChazzC]

I understand the concept of how to do it but my question is this.

EVERYTHING I have to do this with is MT3 tapered. I don’t want to put something tapered in my chuck. Is there a part I need to get so I can put something tapered in my chuck? Or is there a live center that’s straight and not tapered for the chuck? What am I missing here?

What is the taper of the sprindle? If MT3 you’re ready to go, if larger you can buy a larger center (you’ll need it eventually to turn between centers) or an MT sleeve.

 

[Tournele]

Put a piece of round stock in the chuck and turn it to a point. It will be true to the spindle axis.

here's an easy-to-use, effective solution

 

[MrWhoopee]

Put a piece of round stock in the chuck and turn it to a point. It will be true to the spindle axis.

This is how most of us do it these days. No need to remove the chuck and guaranteed to run true.

 

[Nutfarmer]

Most lathes if you remove the chuck have a tapered spindle that will take a Morse taper dead center directly or with an adapter. The easiest way is as all ready described.

 

[paynerd]

Put a piece of round stock in the chuck and turn it to a point. It will be true to the spindle axis.

If I do it this way, which sounds like is the easiest way to do this, do I have to make sure my headstock is in alignment with my bed/rails/carriage or will this take all of that out of the equation?

 

[RJSakowski]

If I do it this way, which sounds like is the easiest way to do this, do I have to make sure my headstock is in alignment with my bed/rails/carriage or will this take all of that out of the equation?

The purpose of aligning the tailstock with the spindle axis is to prevent turning a taper when turning between centers. If the spindle axis is not parallel to the bed ways, you will cut a taper. Twisting the bed can correct this but doing two wrongs to make a right isn't the proper way to do this.

If the spindle axis isn't parallel to the ways, the further out from the headstock you go, the grater the offset will be. If you are aligning the tailstock center with a headstock mounted center, it will be correct at that point but as you move to the right, which is was you would be doing when turning between centers, you will no longer be aligned.

For this reason, I would first align the headstock to the bed. then I would twist the bed, if necessary so that I wouldn't be cutting a taper, as determined by the two collar test or the RDM test. When is was satisfied with that alignment, then I would turn my attention to the tailstock.alignment. Personally, I would align the tailstock center to center only as a rough alignment. I would do a final alignment by mounting a bar between centers and either do a modified two collar test or a modified RDM test. Actually, If I were turning a shaft, it is p4robably quickest and arguably most accurate to make an oversized trial cut and measure with a micrometer at either end and adjust the tailstock accordingly. Doing so will ensure that the tailstock is properly adjusted at the distance you are working with.

 

[paynerd]

Alright this is going to take some time to digest. First thing I need to do is the RDM test. Looks easy enough. I’ll probably have more question. Thanks for your help!

 

[Jimsehr]

Think I would take the spindle out of the tailstock. Then turn a piece of stock in headstock. Then slide tailstock forward till it slides over that true turned diameter.