Here is the ring with the leather piece sitting in it. It looks black because it is soaked with oil.
I thought about making a new mounting pin but then decided to just lengthen the original. I drilled out the oiler thing that was in the end and then 45 degree chamfered the end as can be seen.
The welded in piece has a spigot that was a press fit in the end of the pin, it is also oversize on the OD. Here the pin has been re-set up true and the welded in piece centre drilled.
Here is the pin with the end machined to be a close slide fit in the ball race bearing. I have not drilled up the pin for a grease nipple because with the grease sealed in there it will last a long time and the grease only lubes the bronze bush which only gets any work when the safety clutch comes into operation. To work out the position of the circlip groove I simply did a dry assembly of part A and part S without springs and balls and measured the distance from outside to outside of the bearings then added .010 inch so there will be clearance between Part A and S.
The leather seal retaining ring has been pressed in, the bush and balls are greased and it's ready for assembly. I held the pin upright in a vise, slipped part A on then slipped part S on, compressed it by hand, clamped lightly with a clamp so I could use both hands to fit the circlip.
Ah! Thank goodness that's finished. It spins very nicely on the bearings. They are normal ball race bearings, I had thought of using sealed angular contact ball races because of the thrust exerted by the springs but when I found out the price of sealed angular contact ball races I changed my mind. The 6001's shielded or sealed are so cheap, it doesn't matter if they have a shorter life. Despite the axial thrust on these bearings I think they will still have a very reasonable life expectancy. Also, while I had it dismantled I filed all the sharp corners off the edges of the tooth crests so the toothed belt will have an easier life.
Mounted up and looking good, it spins easily, quiet and true without any slop whatsoever. I have since loaded the springs with 2mm thick spacers but I can still stop the chuck by holding my hands around it. It's pretty strong with the 2mm spacers but I have already made 3.5mm spacers and will change to them as soon as I get a chance. I don't want to disable the safety clutch unless I have to but I do want it to be able to deliver a strong drive.
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