Eagle Surface Grinder Model 3 Rebuild - Spindle Refurbish

My MK3 is almost as described by Tony on lathes.co.uk/eagle
with one difference, at the back there are two deep grove ball bearings.


He writes:
Sized imperially, the ball races consisted of two opposed angular contact ball bearings behind the wheel with a single deep groove ball bearing at the drive pulley (rear) end. Interestingly, if the angular contact bearings are dismantled (they push apart) an owner reports that they can be revived by polishing the races lightly with diamond paste, fitting new balls and lubricating with ordinary lithium grease.

The spindle of my variant runs in two angular contact bearings, each pair in back to back (DB) arrangement. The preload adjustment is not clear, need to do more research here. The bearings are of imperial dimensions ID 25.4 OD 63.5 ( 1" x 2.5" ). 

The spindle assembly is pulled out to the front, there is a hole in the middle to restrain the shaft from rotating.

Once out, the bearings pull apart and the balls measure in at 10.30 mm since this is an imperial sized bearing my thinking is this was probably a 13/32" ball. (10,31875mm ). Initial measurements of the races ID and OD confirm this.

I could not find a suitable new replacement for the Bearings.
The replacement is still manufactured under the following names from R&M, SKF and some other brands.

RMS8    MJ1 - Deep Grove
AMS8    MJT1 - Angular Contact




Since the bearings show significant wear, there are two options under consideration.

1) Use 7006 bearings 30x55mm and machine new sleeves to fit the 1" shaft and 2.5" outer seat.

2) Do what  Tony describes. Order new balls, polish the races and see what I get.

Colchester Chipmaster Bed Grind

After devising a design on how a portable bed grinder should work, and coming up with the theoretical tolerances a home build solution would yield, it became apparent, this is a perhaps a bit ambitious. And if I want to restore the lathe to better than "factory" specification, this might be the risky route.

The Machine tool re-seller, from whom I bought my Eagle Surface grinder, named a very reputable company they use for rebuilding. I contacted the owner and after some negotiating, he agreed to regrind the bed only, although they specialize in complete rebuilds. Henning a very knowledgeable gentleman with a wealth of experience in machine tool rebuilding from Atlantic Enterprises situated in Johannesburg, assisted me in regrinding the bed on their Churchill lathe bed grinders.

When inspecting, it immersed that the two v-ways where aligned, but the flat ways were not in alignment, most likely a factory defect, which probably is not a big issue if the tail stock and head stock are custom fit to the machine. 

This misalignment gives me indication, the head stock is custom fit. So now my next problem how to measure the error of the head stock on the surface plate. Here I will have to come up with an accurate technique to establish the spindle center height front and back. the problem is the spindle surface is not freshly ground.