With the headstock done, the book suggests turning down 3″ of the temporary spindle / boring bar to 1/2″ diameter, such that it could be used as an arbor to machine the leadscrew drive pulleys. A left handed turning tool was needed for the operation, and it would be my first attempt at grinding one down from an HSS tool blank. There is a good amount of information on the internet ( and in a couple books I have ) about grinding tool bits, but it definitely seems like it will take some practice. After grinding the tool down a few times, it finally cut ok.
The turning operation went fairly well, and it seems like the lathe is at least rigid enough to handle light cuts on a piece of 5/8″ cold rolled steel. I’m not really experienced using a lathe at this point, so it could just be my lack of knowledge, however some things definitely seemed like they needed improvement. When advancing the cutter into the stock it would make a crazy squealing sound, though once I was on my way with the cut it sounded normal. Could have to do with the alignment of the tool with respect to the center of the spindle, though it is either on center or slightly above. It could be the cutter as well, since I’m no expert with regard to that. When cutting the area where the square hole is ( for the boring bar cutter ), the spindle would deflect a bit, however the rest of the lathe didn’t really budge at all. I can see how a tailstock with a center would be helpful when turning a long piece.
I don’t have any photos of the operation, however I did take some video, so definitely checkout the video link at the bottom of the post if interested.
In order to test the diameter of the spindle, I used both digital calipers and a 1/2″ end mill holder from my mill. My ability to accurately use the calipers is still a work in progress, however I definitely felt that the end mill holder would be accurate enough.
Photos of me testing the finished spindle:
All in all, at least according to the 1/2″ end mill holder, it turned out to be quite a good fit.
Video of me Turning Down The Temporary Spindle »
Cheers,
Morgan