Bob Smeltzer
Member
That is correct. Once you unchuck the mandrel, it is virtually impossible to retrue it close enough for this type of work, where you are dealing in .0001 dimensions.
I'm not saying you can't, but it's no big deal to just turn a fresh one each time you set the lathe up to do the operation.
In my first post in this thread, that little known is to a YouTube video of me doing necks on our EE.
I make the mandrel out of a grade 8 bolt Then just toss it in the scrap!