1988 Fadal 4020 Conversion Thoughts: MESA 6i24 + 7i49 + ?

I have taken apart my Y motor again as I wanted to get to the bottom of the roughness in the shaft. I believe all the bearings are shot in this motor + the tachometer commutator is not concentric with the shaft and I can visibly see it moving the brushes up and down .5mm or so out of round, it also makes a clicking noise at a certain spot on the shaft that varies with rotation.

Also the resolver is a more accurate 3 arc minute variety it turns out. But bad news is the bearings inside resolver are totally gone.. super rough spinning. I have disassembled it and the rest of it looks okay but I would at least have to replace these bearings.

The bearings are 0.5" OD 0.125" ID and 0.109" wide which is a very unusual size. I could make spacers to adapt a standard size 0.25" OD bearing to 0.5" OD..

Again re-evaluating options

They fail quite commonly on these Fadal machines.. It is usually because of improper shaft alignment where the flexible aluminum coupling puts extra stress on the bearings. It is also likely original and 30+ years old and I believe this entire machine has had a rough life with high duty cycle production. According to all the Fadal message boards the resolvers are a common failure item for the Fadal and they recommend you keep a spare handy.

At least the other two axis motors seem to have been replaced recently along with their resolvers / tach.