I mentioned in another thread (parts washer solvent) that I had to sort out an urgent job - a mulching/flail mower whose bearings hadn't been greased for many years. The main rotor bearings were pretty straightforward, just requiring the replacement of the wide inner ring bearings and their housing. The trickier part was the rear roller. This is a 1.7m long tube with 25mm shafts at each end. The un-greased bearings had long ago seized, meaning the shaft at each end had eventually broken free and slopped around in the bearing for many years. The 25mm shaft looked like this:
IMG_3599.jpg

Which I think doesn't quite qualify as a "press fit". The worn shaft had a taper to it, meaning I couldn't use a bush. My lathe's spindle bore is 40mm, which isn't quite enough for this tube, and between centres only goes up to 1m, so not an option.

So raiding my (s)crap pile, I came up with this work of art:
IMG_3600.jpg

You might recognise the "bed" as some gal fence posts.

Added some weld while slowly spinning the part using my Ozito precision rotator.
IMG_3601.jpg


And she's all filled up. Turns out that using a dead centre (made from sharpened 12mm threaded rod) is not the best option, as once the heat from the welding has burned off whatever oil was put in there for lubrication, it makes all manner of unhappy noises.
IMG_3602.jpg

Then it's time for my precision toolpost grinder.
IMG_3604.jpg

And a file and emery paper that got it to ~24.95mm
IMG_3603.jpg

Turned out better than I expected, but then again, my expectations were pretty damn low.
Attached Images




Read the full thread at metalworkforums.com...