This is a detail of the pillow blocks that will hold the spindle bearings. They aren't drilled for the bearings, yet, but I do have the bearing inserts; they're simple sintered bronze, impregnated with oil, similar to the Oilite brand if not actually that brand (they're in the basement, and I'm not). I intend to cut a slot in each insert so that I can shim or sand the blocks to adjust the tightness of the bearings. Each bearing also has a flange, which will act as a thrust bearing. The front end bearing will take up the thrust from the lathe tool against the work, as transmitted by the chuck or center; the rear one will serve to control end play in the spindle and act as a backing plate for the stud gear that drives the change gear train for thread cutting.
The pillow blocks seen here will be marked for center, temporarily bolted to the headstock, and the holes drilled along the join line, substantially undersize, on my drill press. Once that's done, the headstock will be mounted on the base plate, and a boring jig using my 3/8" hand drill for power will be mounted on the ways and translated along them to ensure a round and parallel bore -- an operation called "line boring" which is a corruption of "aligned boring."
Gingery states that it's impossible to move the boring bar and get a true bore without spending lots of money on special tooling and equipment. On this point, he's simply wrong; the exact same geometry that gives a round, parallel bore with his temporary tailstock and traveling headstock setup will also apply when one moves the temporary tailstock -- as long as the movement is parallel to the ways and the boring bar setup is rigid, it doesn't matter which part moves. I've got a good bit more work ahead, though, before I'm ready to prove this.
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