23-06-2019, 04:23 AM
When I last worked on a diff the pattern was consistent and I had not heard of the tendency for carrier to be bent so did not check. From tales of engine lockups etc I can see how it occurs...
Sorting this sort of problem can require machining in toolroom territory and somewhat beyond the realm of many “mechanics”. Desired run out is better than that of many lathe chuck jaws.
How do rebuilders check runout prior complete assembly? Just sitting the side bearings on V blocks or equivalent hardly seems adequate. Turning without bearings on V blocks would not adequately involve the bearing shoulders. I suppose the ideal would be to hold side bearings stationary between chucks or equivalent in a medium lathe and rotate the carrier. For most probably simpler to assemble.
If bent, machining of halves independently using the bearing mount set to run absolutely true seems promising but cannot touch diameters so unlikely to totally avoid problems when bolted together.
Much depends on how the carrier was mounted for skimming. Whoever did the work, what were their instructions? Simply packing in chuck to remove the “error” probably the simplest.
A lot can be achieved with a scraper, engineers blue, fine emery paper, straight edge, a piece of cadged plate glass etc....
Re the roller bearing question a few days ago I looked up the 1928 Austin reprint diag on p204 of Wyatt 3rd Ed. Checking again I note that .003 is given as runout limit and scraping is suggested. This reprint must be available on the many websites.
Sorting this sort of problem can require machining in toolroom territory and somewhat beyond the realm of many “mechanics”. Desired run out is better than that of many lathe chuck jaws.
How do rebuilders check runout prior complete assembly? Just sitting the side bearings on V blocks or equivalent hardly seems adequate. Turning without bearings on V blocks would not adequately involve the bearing shoulders. I suppose the ideal would be to hold side bearings stationary between chucks or equivalent in a medium lathe and rotate the carrier. For most probably simpler to assemble.
If bent, machining of halves independently using the bearing mount set to run absolutely true seems promising but cannot touch diameters so unlikely to totally avoid problems when bolted together.
Much depends on how the carrier was mounted for skimming. Whoever did the work, what were their instructions? Simply packing in chuck to remove the “error” probably the simplest.
A lot can be achieved with a scraper, engineers blue, fine emery paper, straight edge, a piece of cadged plate glass etc....
Re the roller bearing question a few days ago I looked up the 1928 Austin reprint diag on p204 of Wyatt 3rd Ed. Checking again I note that .003 is given as runout limit and scraping is suggested. This reprint must be available on the many websites.