south bend headstock alignment?

The shaft was probably flexing since you were not supporting it with the tailstock.

No I checked that pretty well. I blued the part after the cut and ran the cutter down the length. It scribed a light line down the length and never put any pressure on the tool. I took very light cuts and had a great finish with no chatter. I took maybe a couple of thousandths off the last pass. I'm pretty sure it's misaligned.

Correct. The tailstock end was being pushed away from the cutter and it was allowed to move

The rule of them is 3 diameters at most before you should use something to hold the shaft. You are about 6 diameters

Gunner

I'm not sure but doesn't the South Bend headstock align on one of the bed Vee ways?

I'd still say the workpiece may be flexing. Try the same test with a piece of 3/4"-1" rod. that shouldn't flex.

JB

RKL means unhardened, right? My 10L is an RKX with hard ways. Could they be worn at the head end enough to shift the carriage? jsw

The shaft could still be moving a little or misaligned in the chuck. If you want to check the alignment you can use a test bar or make one but the readings would be meaningless unless it is supported and centered on the tailstock, AFAIK.

 I kept checking the diameter

I am confused. If the tailstock end is being pushed away from the cutter, wouldn't the tailstock end be bigger?

Dan

The tailstock end is the smaller diameter. As the piece approaches the headstock it gets larger.

It started as 1.25 and I took it down to .75. The tailstock end was the smaller end.

Yes and that is not the problem. I am pretty sure it is an alignment issue.

If the spindle isn't parallel to the ways I think you would see a difference in how a pointed rod that spins true aligns with the tailstock when chucked close, and when extended. This assumes the inner ways that align the head and tail aren't worn or damaged.

The rod could be a sharp pencil in a 4-jaw, adjusted to not wobble at the point.

There might be a chip under the headstock if a previous owner had removed it. Can you detect a gap at either end with a magnifier and bright light? jsw

Google "rollies dads method" to first check alignment , then if you do indeed find it's off check for chips or swarf between the head and the vee way that's supposed to align it . Any chance the head bolts got loose and were re-tightened without checking for debris under it ?

Then perhaps the bed is twisted? phil k.

If the RKL is on a sheet-metal cabinet like mine that is very possible. There is a bed twist adjuster in the base on the tailstock end, the two screws in the round tags. jsw

Eeep!!....absolutely correct. I once again, read it wrong while I was doing something else. I need to pay far more attention or keep my mouth shut.

Indeed...his head stock is out of alignment...or...more likely the ways are worn close to the headstock.

Gunner, who just woke up and will let others tell him how to determine if this is whats happening

This is a very good way to check alignment or wear..or both

Gunner

1) Hang a piece of 1" material about 6 inches out of the chuck and then carefully turn the last 1/2 inch or so that is closest to the tailstock down to exactly .950 diameter. 2) Cut away all of the rest of the bar except for the last 1/2 or so that is nearest to the chuck down to about .900 or so, for clearance..... 3) Carefully cut the last 1/2 in or so that is nearest to the chuck down to exactly .950 diameter. 4) Finally, loosen and re-align your headstock by bumping /shimming/ scraping or otherwise adjusting until an indicator placed on the carriage produces the same reading at both of the .900 diameters.

See correction below...