Lock quill when scraping / measuring tailstock alignment?

[jim rozen]

"On a Hardinge TS that doesn't split you have to lower the headstock to compensate for the worn TS bottom. "

On a lathe without a hardened quill one can cheat - make a new one with the bore offset. Cf my 7" pratt whitney bench lathe. A new hardinge tailstock has such a good fit one can barely see the play with a tenths-reading indicator. It's amazingly nice to use a machine like that. It's as good as the boley lathe at work.

 

[Richard King]

Thanks Jim... I did mention this in my post. " On a Hardinge TS that doesn't split you have to lower the headstock to compensate for the worn TS bottom. I didn't put Turcite under the TS of both types as it was to slippery and would move when boring."

 

[jim rozen]

Agree - was saying you can cheat in some cases. I did and worked nicely. Also, how the HELL does hardinge make those tailstocks so nice?

 

[jwearing]

I believe the OP (1 class) all are students

Richard, I've never taken your class, I'd love to but my free time comes in small increments, and only early in the morning.

The answer to the question is Yes tighter the lock like you do when running the lather. Common sense tells you If it the quill moved more then .001" its time to repair the bore / quill before scraping it.

Thanks!

 

[eKretz]

One could also slightly offset bore and hone the tailstock housing a little higher to provide stock to remove on the bottom. You'd of course need to chrome and grind the existing quill to re-fit it or make a new one also. Jim's idea of putting a new larger female taper in a little higher (or was that just re-make with original taper, but offset higher?) should work also as long as there's room. None of those options require altering the headstock.

 

[jim rozen]

For the small pratt whitney, it was a new quill, with the bore offset to center once I had re-scraped the badly worn TS underside. For the potter lathe that was easy, it came without a tailstock. I cut down a SB one and modified the underside to fit that bed.