Mill/Drill Spindle Bearing

[trainman2]

Great thread on the subject, still reading through it. I did get the bearing out before seeing it.
I got really frustrated trying to remove the lower bearing because the slot in the spindle casting was not deep enough. The race was not proud of the slot. To make things worse there was not much to get a grip on. I pressed a piece of wax into the area above the race to see what I was working with and found I only had ~.030 to grip on.
To get the race out I took a piece of 1/4X1in steel bar drilled a 1/2" in the center for a bolt. I then turned in to about 1/8th over the ID of the race. I cut a chamfer on the face to provide a knife edge on the perimeter that would fit into the limited space above the race. I then bent the bar slightly so that I could press it through the race It snaped into place and I was able to press it from the top of the spindle forcing it further into the grove and the race down. This was not sufficient to get the race out but did move it far enough that I was able to get a drift on it. I fabricated the drift welding the bar previously described to round bar cutting one side of the flat portion off. I was able to tap around and get it out.
This took two days. The lower bearing was really a tight fit the upper was much easier to get out. I am considering trying using dry ice to shrink the bearings for installation. I put the bearing in my home fridge freezer ~0 degrease Fahrenheit, and it shrank about >.002".
Do you think this will work?

 

[mikey]

Shrinking the bearing might work but what will you do if it only goes partially in? A better option is to use an arbor press or hydraulic press to install your bearings, using pressing adapters to put pressure where it is needed. If you don't have a press then make the adapters and go to most any machine or auto shop and they will have a press. Right tool for the job and all of that.

 

[trainman2]

I have a press but am reluctant to remove the quill. How difficult is it to get the return spring in and out?

 

[mikey]

The spring is a non-issue. Just grab the housing containing the spring and loosen the screw in the center of the housing. Once the screw is out, slowly unwind the housing to take tension off the spring. The end of the spring is held by a screw; you'll figure out how to get it loose. I listed the order in which you need to remove parts to get the quill out in that thread I linked you to. You need to remove the quill in order to get the spindle out so you can change bearings and races.

 

[trainman2]

Does the pinion come out without having to remove the fine adjustment assembly? The spring seems to be held by a roll pin. I have not removed the cover yet but there is not really much tension on it.

 

[mikey]

Have a look at this and see if it helps.

 

[trainman2]

That is fantastic. Where did you find it?

 

[mikey]

I wrote it awhile ago but forgot about it until today.

 

[trainman2]

Finally got the quill out. The plastic knob camp off the screw I will replace it with a cap screw, not sure what the purpose of the knob was. I did have a problem getting the end of the spring to unhook from the pinion screw should go back on easier. I am still trying to source the bearings for a reasonable price and all from the same supplier.

 

[trainman2]

I am waiting on the replacement bearings and planning the reassembly. Both inner races of the spindle seem th
o be a press fit. There are a pair of jam nuts on top which implies one bearing is a slip fit and the nuts would be used to preload both bearings as you might do on a car. But if both are pressed on, I don't know how this would work. I tried fitting the old bearings neither seems to be a slip fit.
Any suggestions on how the reassembly should be done?