Centering tool

I saw this on the MIT videos posted earlier by eil and decided to make one:



Basically it is a bar turned to 1/2" then turned to a point. It is center-drilled then the end is cut off. A spring is inserted to hold the tip on.

You insert the tool in a chuck or collet adapter. The tip goes in a center-drilled hole or a punch mark. You use your fingers to feel if the tip is still aligned to the shaft. You can easliy feel an 0.002" offset.

Saw it first used on a drill press to make sure chuck is centered over punch marks. Then again on a mill.

Tried it on my lathe. worked well. I knew the tailstock was about 0.001" off. It showed up and I was able to adjust it out. The surprise was it showed my tail stock is about 0.002" low. Not sure how to adjust that out

Hi,

that's neat. How have you attached the spring to the point, spot weld?

Regards
Peter

There was a small "nub" left when I cut the tip off. That made it easier to solder the spring to it.

Hello Shenion,

if your tailstock has a base and the main part (so as to adjust in a horizontal plane) I suggest dismantling it and use a 2 thou shim to lift it up?

Alec

Yes, that is the plan. I need to find if it is just low or angled. I bet the base has worn down on one end as the hold-down bolt is toward the ram end. I will need to shim up only one end then. Will try mounting a center in the spindle and tailstock and see if it is different with a shorter extension.

I will be ordering some shim tape and look at it in more detail later.

I also need to take it apart to fix the set screws. They act like the ends are angled. You turn them and the tailstock will move one direction then the other.

DTI?

I have a magnetic dial gauge, but it is not movable.

Dial Test Indicator (i.e. your dial gauge)