| Gallery, Projects and General > How do I?? |
| Half Nut Adjustment? |
| << < (2/3) > >> |
| wongster:
Andy, Thank for taking the time to write. The apron, lead screw, half nut, and the bearing at the tailstock end were all taken off the lathe and off each other :D I don't understand the part on skimming off the top of the apron. As the lead screw now sits lower than the centre of the half nut, wouldn't that lift the lead screw higher when the half nut is engaged? I took a video and posted it on my blog showing the lift. I don't know about Mercedes, but I heard from friends who own BMW that they experienced quite some problems with the electronics. As to Audi, don't know they solved the clutch issue. I'm still trusting the good old Toyota. Most mechanics know how to fix one. Regards, Wong |
| David Jupp:
I know of one case where the swarf in the half nut threads was not obvious - nut just looked grey / worn. It took a good 'dig out' with a scriber or nail to even reveal the extent of the problem (in that case, after a clean up the half nuts were near perfect). I don't know if this is an issue for you or not - but since it doesn't require any significant work to the lathe, it is worth checking very closely before attempting more drastic fixes. |
| wongster:
I'll do so. Sure beat having to do anything else to the lathe, especially when my lathe is only 5 month old. Regards, Wong |
| andyf:
--- Quote ---I don't understand the part on skimming off the top of the apron. As the lead screw now sits lower than the centre of the half nut, wouldn't that lift the lead screw higher when the half nut is engaged? I took a video and posted it on my blog showing the lift. --- End quote --- You are quite right, Wong. You would need to lower the apron if you took that route, but that would take the pinion a little out of mesh with the rack, so for a perfect job you would need to lower the rack as well. But if the existing wriggle room on the bearing fixings isn't enough to stop the leadscrew bending, dropping the apron with shims would avoid the need to enlarge the fixing holes, and a little more backlash on the apron handwheel would probably be acceptable. This, of course, assumes that it isn't just a lump of swarf which is causung the problem, though your video seems to show a lift of a millimetre or two, so the lump would be easy to spot. Andy |
| mzt:
While I was looking at the video here, I had the impression that the upper portion of the half nut stays firm in place when the engaging lever is acted. Should it not go down towards the LS of the same amount the lower HN goes up? Marcello |
| Navigation |
| Message Index |
| Next page |
| Previous page |