Extra Wheels for Baldor
© Frank Ford, 2010, Photos by FF For the big view, click the small photo.
This is another of those shop tooling jobs I'd put off for years - adding some extra wheels on my buffer. Here's a blurry "before" picture:
And, here it is with its armature removed, also nicely out of focus:
I took the armature out so I could add some threads to lock the buffs in place rather than simply stacking a bunch of spacres on the shaft. I went to this extra trouble because it would give me more flexibility in mounting buffs, and because I was ready for a slightly challenging project.
It would have been easy enough to suppor the amature by its drilled centers, but my lathe has nowhere near the length capacity needed, so I knew I'd have to support the outboard end with a steady rest. So, I set machined a quick piece to the same diameter as the end of the armature shaft:
And, using that piece as a guide, I set up my steady rest for a smooth running fit:
Then, when I moved the steady down to the right end of the lathe bed, I knew it would be in good alignment with the lathe spindle center.
Just for good measure I protected the armature bearings from swarf with some stretch wrap:
The armature shaft was 30mm in diameter, so to provide a shoulder against which my new buffing collar would stop, I turned the shaft down to 1.125"
I had no problem with concentricity using a collet to hold and drive the end.
Next came the threading. I had to choose NF threads because my lathe won't cut anything coarser than 10 T.P.I. so 1-1/8 - 12 it was:
Right hand threads for the right end, left hand for the left, of course.
I made matching collars for both ends, threading them on the lathe:
To check the fit, I simply took the 5" chuck off and tried the threads on the shaft. At the time it seemed easier than dealing with that long armature on the lathe:
What a good time to use my two-jaw chuck with its big aluminum soft jaws to avoid marring my nicely turned discs I'd made to use for stop collars. I clamped the jaws down onto a simple block and turned them to fit the discs:
Drilling and boring:
Then, over on the mill, I drilled and countersunk for a clamping screw:
I just hand-tapped it all the way through:
Then splitting the rings with a slitting saw, my little collars were complete:
I gave each of the round nuts a hole for a pin spanner:
Just for fun, I made a wrench from some cold rolled steel, first cutting the round sections on my little Rusnok mill, using a "sacrificial" piece of aluminum under the part to avoid damaging my fixture plate:
I usually keep the rotary table set up on the Rusnok for these little occasions.
After drilling for a dowel pin, and some hand finishing, I had a nice little dedicated spanner that will hang on the buffer column:
I had this big slug of 12L14 steel round, so I made up a little temporary sled for my Delta band saw, and cut off a couple of slices to make stabilizers for the buffs:
Some process shots of making the stabilizers:
I set up my slotter to make a keyway the two stabilizers that would be on the inboard side to keep them from rotating:
And I beveled each of them, using the lathe compound at an angle, finally boring a step for them to receive the nuts and stop collars:
As I'm tightening the inner stop collar, note the little hole in the lower portion of the shaft. I drilled it to tap in a roll pin that would engage the keyway in the stabilizer. I didn't provide a slot in the stop collar to slide it over the roll pin because I don't expect that I'd ever want to remove it:
After much ado over a buffer, here's the modified shaft, ready to load on components:
And, here it is with the buffs stacked in place:
I can accommodate a wide variety of widths now!
A final portrait with a green sheet hiding all that junk on the wall behind:
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