Pretty good going for 30-year old bearings. The bearings were in great condition, with barely any sign of wear. They are supported on the inside by a circlip (visible in the pic above) and a 1mm shim washer. The bearing shells are a close sliding fit in the bore. To replace the bearing I used the old bearing shell to tap it back into place. I got it off the shaft by tapping around the edge of the bearing with a suitable punch/drift. The front bearing (in the pic) is pressed onto the shaft. The rear bearing is a sliding fit onto the shaft. Spindle and front bearing as removed with a couple of light taps with a copper-faced hammer. Having said that, the bearings were not worn and looked original (1989 vintage). When re-assembling, I’d suggest to go heavy on the grease to make sure a lip of grease surrounds the bearing, to catch any swarf. I was surprised to see that there is no seal to prevent ingress of swarf. Because I was trying to fix a known problem with my lathe, I took it off (if you just want to check/replace the bearings, then don’t take it off). Hobbymat universal md65 lathe manual manual#It is not necessary to remove the chuck back plate – in fact in the manual they advise against it due to the risk of misalignment on assembly. With the locking collars removed, ready to tap the spindle out. My lathe did not come with the part labelled number 4. I have reproduced the instructions and exploded diagram below. Removing the spindle is straightforward, and is described in the manual. My brazing skills need some work… I didn’t bother to tidy them up too much. I rounded the corners slightly to make them more comfortable to use. The handles are rather heavy for this application, but they were what I had in stock. I glued it into the spanner body using Loctite 603. I turned a 4.5mm diameter section to fit the collars, then a 5mm section to fit the reamed hole in the spanner, and finally I left the last 1mm at 6mm diameter. I then added a flat where the handle would be brazed on, and cut the round into two pieces (to make the two c-spanners). I made up a pair of c-spanners by turning the rounded part (32mm ID x 50mm OD x 10mm deep), then adding a reamed 5mm hole for the pin. The holes in the collars are 4.5mm diameter, about 2 to 3mm deep. The spindle assembly is held in place by two collars: one to apply pre-load to the bearings, and the second one as a locking nut. Hobbymat universal md65 lathe manual how to#When I figure out how to adjust the bearings for pre-load, then I will add details in a separate page… Details of part numbers & sizes for the bearings and shim washers are below. Pulling the spindle is not a difficult or time-consuming job. The front one was clearly dished, and the rear one was a bit wavy, rather than flat. The shim washers however were in less good shape. I could see very little sign of wear in the bearings, so I could have just cleaned / re-greased and re-installed them rather than installing new ones. The existing bearings in the lathe were marked with ‘Poland’ and ‘USSR’, so I think they were the originals (from the lathe’s manufacture in 1989). I was keen to show off the engineering skills I had collected, however the 90mm-long piece came out tapered…īefore messing with the screws clamping the way to the head, I decided to at least have a look at the bearings. Paying some attention to the spindle bearings came about after a very good friend (and also my inspiration for all this machining malarkey) needed a simple alignment tool to aid assembly of a powered bifold door.
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