Posted by BillS on February 29, 2012 at 06:47:13:
In Reply to: holding a hob on Barber Colman posted by BobM on February 28, 2012 at 15:12:49:
As I recall, the outboard end was supported in a steel sleeve with thrust collar that ran in a bronze bearing in the outboard housing. The outboard shaft of the hob had an integral collar to radially snug against the outboard sleeve. There was a threaded end in the drive end only of hob for a draw bolt. after assembling, and before tightening the outboard bearing housing to the table, you exert pressure against the hob to take out any radial play in the assembly.
A variation on that were hobs with integral shafts where the outboard end was tapered and fit in a tapered bearing (or was it a tapered sleeve?) Anyway, it had a drawbolt for the drive side which secured it along with a drive key, and the outboard housing was snugged radially against the hob to remove endplay.
Of course, larger hobs with bores and keyways were mounted on a drive shaft with spacers and a steel sleeve with thrust shoulder. The arbor was threaded so that the hob, spacers, and sleeve were tightened together as an assembly. This sleeve ran in a bronze bearing with mating thrust collar pressed into outboard housing. Again, the endplay was removed by snugging up the outboard housing against the hob/arbor assembly.
Post a Followup