12” x 37” Lathe Tailstock Clamp Improvement

[C-Bag]

Very nice and great info. I've got a similar plate on my 9x20 tail stock and have struggled with it slipping too. It never occurred to me it was the cast iron on cast iron that was part of the problem. I'd gone to a lot of trouble to get rid of the locking bolt and adapting cam lock kit that Little Machine Shop sells for the smaller 7x lathes onto my 9x20. With proper adjustment it works good but I can see now the next step is to get rid of that bottom plate. Pardon the noob question but why do you think the clamping bolt is offset?

[Paul Jones]

C-Bag, thank you for the feedback. I have been thinking about doing this improvement every since the used lathe arrived last January but I was thinking in terms of milling the part. Then I remembered how I built a small metal lathe when I was a teenager using various rectangular shapes of stacked steel bars joined together with machine screws and no milling required.

I too thought the clamping bolt was centered in the tailstock and had already marked the center of the plate for drilling during layout. I decided to double-check the tailstock locking bolt position before drilling. I found the tailstock has a machined ring opening at the top of the locking bolt that slides on an eccentric cam. The ring is used for up-down unlocking-locking but the ring doesn't slide all the way over to the exact side-to-side center due to the way the cam is machined. The locking bolt is slightly closer to one side of the tailstock and the 9/16" hole was positioned to accommodate the offset.

Thanks for asking