Spooky McGhee breaks lathe part 2
2The spindle bearings gave up the ghost, so now it's time to tear down the headstock and attempt a repair. While we have the machine torn down for the repair work we will also be attempting a repair on the hydraulic vari-speed control. The spindle speed selector slips and will not stay in position (and as a result will not maintain the desired rotational speed) unless a wedge is jammed under the plunger, essentially forcing it to hold position. We will be replacing the hydraulic hose and tearing down the variable speed clutch above the motor in order to service/clean/repair/restore the speed control assembly to proper working order. Since we removed the headstock from the machine we will need to realign it during reassembly. That will be one of the most critical steps in the process, the other being the perfect alignment of the new spindle bearings and gear train. You see, if the headstock is out of alignment by even a couple ten-thousandths of an inch the machine will no longer be as accurate as it could be and will cut a (slight but undesirable) taper. That being said, we will be aligning the headstock to within half a ten-thousandth of an inch and we will do the same with the tailstock after the headstock is perfectly aligned. We will also be replacing a few worn bronze bushings in the saddle of the machine, mainly for the Z axis handwheel. It is so worn out that the wheel feels as though it is about to fall off. The bushing is bogus and will need to be replaced. The same goes for a bushing on one of the headstock feed gears, where the inner diameter of the bushing is worn by almost 20 thousandths. It will also be replaced. Our hope is that after the repair work is completed the machine will be in tip top shape and will run better than ever.