Shopsmith Forums

I found excessive end play on three of the current version quills, out of three I had available to check. My PowerPro has a relatively new quill, about 18 months old. The other two were a spare removed when I installed the PowerPro and my shorty (Mark 4) both 15 to 18 years old. All these quills have the one-piece spindle. End play measured about .006", enough that they made noise when you rattle the spindle in and out.

I repaired the PowerPro and the spare by replacing the outer bearing. The bearings are 6203-2RS (sealed bearings). The bad ones are labeled FLT4 manufactured in Poland. I chose Timken as replacements. These completely resolved the problem. What I found strange is that neither of the 'bad' bearings show any other sign of a problem, they are smooth, quiet, and have not lost grease. I removed one seal and did not see any sawdust etc. on the inside.

In working on this I noted that the inner bearing does not contribute to controlling end play. While the inner race is seated solidly on the spindle, the outer race is not seated and fits relatively loosely inside the quill barrel. It is free to slide in and out.

- David

Metric size difference?

edma194 wrote: ↑Thu Oct 21, 2021 9:57 am Metric size difference?

More likely intentional to allow some lack of straightness in the shaft.(kinda defeats the purpose!)

OR makes assembly easier.(ditto)

If the bearing is 'metric' then the bore should be also.

JPG wrote: ↑Thu Oct 21, 2021 10:02 am If the bearing is 'metric' then the bore should be also.

The bore could be a better match to the actual size. I've seen all sorts of parts that were made to metric sizes then listed with a standard size that is not an exact match. I'm only making a guess here, it's one of many possible causes.

Just going by feel, the FLT4/Timken bearings seem to have the same bore and outer diameter. Press fit on the bore, snug outer. There might be a slight difference in width, as I had some difficulty installing the snap ring on both Timkens where I had the originals apart and together a few times before deciding a course of action and the snap ring went on easily each time. Sitting here at my desk though, the FLT 4 measures 11.95mm wide (12 nominal) which would not be enough error to explain .006" end play even if the outer race was moving. Sorry for the mixed measurements, but .05mm is about .002". I'll try to check more carefully, but I believe the movement to be internal to the bearing. Which I can't explain on a reasonably new and otherwise good bearing.(?)

Note - The 6203 bearing is slightly larger and not used in the earlier two-bearing quills that had two piece spindles.

- David