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[R.U. Sirius]

Hello everyone,

I have been refurbishing this old Beaver-like station. After replacing the bearings and putting the new wheels on, it was running quietly and without noticeable vibrations. Just in case, a took a sharpie to the wheels, and noticed that all wheels got markings consistently on one side. On the opposite end of the arbor, the wheels were marked on the opposite side.

I took the wheels off, and the same happens with the bare shaft.

I do not have a dial indicator, but have rigged something ugly but functional with t-slotted extrusions and a digital caliper. The readings show consistently that there is approximately 0.25-0.35mm (10-14 mils) of wobble in the middle portions of the shaft on each side. When left-hand side is closer to me, the right-hand side is that much farther away. The ends of the shaft probably travel twice as far, but I cannot measure it due to threads.

Is this amount of wobble tolerable, or should I try and fix it? Does this mean the shaft is not true, or is it possible that this happens due to bearings and the overall alignment of the system? The bearings are supposed to be self-aligning, with spherical outer race sitting in the rubber insert that fits snugly into its aluminum "hat" - everything looks and feels solid.

[Slabbercabber]

There should be zero wobble in a shaft.  But cabbing is a pretty loose thing.  You are holding the work in your hands.  Your ability to hold pressure is much greater than a little wobble.  The only real problem is that it will accelerate wear on the bearings.  Again, I wouldn't worry about it.  It runs at low speed and for most people, very low hours.

[lithicbeads]

Keep your hard wheels as close to the center of the machine as possible.Nova style wheels can absorb
 quite a bit of wobble.

[R.U. Sirius]

Keep your hard wheels as close to the center of the machine as possible.Nova style wheels can absorb
 quite a bit of wobble.

My thoughts exactly, that's how I set it up! Now setting up the water nozzles and drain connection, and should finally be able to try it out next week... whenever I manage to squeeze a few hours in between all the family and work activities and emergencies.

Thank you both for the advice!