buzzfirst wrote:Hello, If you have centers for the headstock and tailstock it should be doable to turn a shaft that length on your 4x machine. Center drill each end of a piece of stock, mount the stock between centers, and turn the 12mm part then turn the 6mm part. When turning between centers you can remove and remount the part without losing your center. You could get the 6mm part close (but big) and test fit it, put it back on the lathe and take another small amount either with a tool bit, file, or emery paper, repeat until done. Do you have an outside micrometer or at least a caliper for outside measurement? Option 2... If you only have a 3 jaw chuck mount a piece of oversize stock, turn the entire needed length to 12mm then turn the 6mm end on the tailstock end of the part. That way you can test fit the 6mm end in your motor without removing the part and everything will stay centered and circular. Start with a good piece of known steel or you may just waste your time. 1/2 inch drill rod would be perfect as you would have just enough to true the rod up in the chuck before you got to 12 mm and it is easily hardened after you get the dimensions correct.
Well, it's a 3 jaw self-centering chuck...and from your description, it sounds like drill rod would work fine. I suspected drill rod would be alright, so thank you for taking the time to explain.
Further, I've got a caliper (micrometer is on the xmas wishlist
)...but didn't really count on using it for close measurements; just eyeballing things, and then test fitting as I neared completion...sounds like I'm on the right track.