I purchased an older Colchester Triumph Round Head Stock Lathe back in January. Finished setting it up in my shop last week. Converted it from 575V to 230V 3 phase using a VFD. See attached picture of my lathe for reference. Used it so far for a small project and seemed to work fine. The gear box seems to run quiet with no unusual noises or vibrations. A
This morning I was shifting the headstock speed range lever from high to low and I noticed when I moved the lever to the right toward the tailstock and the gears started to engage the chuck moved slightly to the right. I checked with a dial indicator from the carriage to the chuck and I am getting close to 0.060" axial movement. I checked the vertical movement of the chuck with the dial indicator on top and prying the bottom of the chuck up. There is less than 0.001" vertical movement.
End play of 60 thou seems real bad - is it possible its just bearing adjustment or is it likely to be something much worse. I was surprised there is so little vertical movement with that much end play in the spindle.
I pulled the left side spindle bearing cover off and I see there is an adjusting nut. See picture of the spindle nut below. The steel nut with the pin holes in the side seems to be tight although I didn't use lot of force yet until I find out what I need to do. There is what looks like an aluminum ring behind the nut with about 20 holes around the outer circumference. I am able to turn that ring independent of the spindle shaft fairly easily by putting a punch in one of the holes and pulling it sideways by hand.
Can the spindle end play be adjusted from outside the the gearbox using that nut or are there adjustments that need to be done from inside the gearbox. I have worked on car and tractor transmissions but never been inside a lathe gear box before. I would appreciate any suggestions on where to start to try and address the axial clearance issue.
This morning I was shifting the headstock speed range lever from high to low and I noticed when I moved the lever to the right toward the tailstock and the gears started to engage the chuck moved slightly to the right. I checked with a dial indicator from the carriage to the chuck and I am getting close to 0.060" axial movement. I checked the vertical movement of the chuck with the dial indicator on top and prying the bottom of the chuck up. There is less than 0.001" vertical movement.
End play of 60 thou seems real bad - is it possible its just bearing adjustment or is it likely to be something much worse. I was surprised there is so little vertical movement with that much end play in the spindle.
I pulled the left side spindle bearing cover off and I see there is an adjusting nut. See picture of the spindle nut below. The steel nut with the pin holes in the side seems to be tight although I didn't use lot of force yet until I find out what I need to do. There is what looks like an aluminum ring behind the nut with about 20 holes around the outer circumference. I am able to turn that ring independent of the spindle shaft fairly easily by putting a punch in one of the holes and pulling it sideways by hand.
Can the spindle end play be adjusted from outside the the gearbox using that nut or are there adjustments that need to be done from inside the gearbox. I have worked on car and tractor transmissions but never been inside a lathe gear box before. I would appreciate any suggestions on where to start to try and address the axial clearance issue.
