Hillbilly tapping drive

[algale]

Love it. You've also accidentally invented the world's cheapest speed reducer. Not sure how much torque you'll get if you were turning or drilling, but there you have it!

[masonsailor2]

That is so cool ! A Shopsmith is the very essence of the McGiver concept. One thing though.....I never met a hillbilly with a 3d printer !!!
Paul

[BuckeyeDennis]

Tried 2 drill chucks on one of my machines and they both fit on but they want to go on too far and contact the plate. Didn't try to tighten them but perhaps the design was such that they didn't want people to use that shaft for anything but a power take off??

Ed

I was wondering the same thing. I noticed that the coupling hub on my idler shaft was quite short, and the end was closed, so it can’t go on too far.

My idler shaft is in pristine condition, and the inner race of a bearing appeared to be mounted on that same diameter. Which says to me that the shaft-diameter tolerance should be well under 0.001”.

My Mark V is a 2005 vintage machine, and I seem to recall that yours are somewhat older, so I have a hunch that Shopsmith changed the shaft diameter to 16 mm (.630”) at some point. I’ll measure the OD with a micrometer tomorrow. Does anyone else with a newer machine know if your chucks and arbors will fit onto your idler shaft?

[BuckeyeDennis]

That is so cool ! A Shopsmith is the very essence of the McGiver concept. One thing though.....I never met a hillbilly with a 3d printer !!!
Paul

All the cool hillbillies have them now ... they’re great for making custom banjo picks and moonshine-jug stoppers!

[JPG]

I am guessing the short idler shaft protrusion is the result of using a water pump bearing/shaft.

[BuckeyeDennis]

Love it. You've also accidentally invented the world's cheapest speed reducer. Not sure how much torque you'll get if you were turning or drilling, but there you have it!

It all depends on how big a drill you hook up to it!

C5EE6709-C335-4A0F-BA4C-3C4EB53A1213.jpeg (62.21 KiB) Viewed 18781 times

[jsburger]

Tried 2 drill chucks on one of my machines and they both fit on but they want to go on too far and contact the plate. Didn't try to tighten them but perhaps the design was such that they didn't want people to use that shaft for anything but a power take off??

Ed

I was wondering the same thing. I noticed that the coupling hub on my idler shaft was quite short, and the end was closed, so it can’t go on too far.

My idler shaft is in pristine condition, and the inner race of a bearing appeared to be mounted on that same diameter. Which says to me that the shaft-diameter tolerance should be well under 0.001”.

My Mark V is a 2005 vintage machine, and I seem to recall that yours are somewhat older, so I have a hunch that Shopsmith changed the shaft diameter to 16 mm (.630”) at some point. I’ll measure the OD with a micrometer tomorrow. Does anyone else with a newer machine know if your chucks and arbors will fit onto your idler shaft?

It does not have to be any longer than the recess in the coupler. So it has a shoulder so it remains on the end of the shaft. If you could put it on far enough that the shaft protrudes through the coupler it will not mate up to the coupler.

I seriously doubt all this. SS has not changed the spindle diameters since the first 10E in 1947.

If SS did not want you to mount a certain adapter (chuck?) on the aux spindle they certainly would not have made a longer hole so that it touched the vent plate.

Pristine spindle or not something else is wrong.

[masonsailor2]

Do they make a DVR drill ?
Paul

[BuckeyeDennis]

I was wondering the same thing. I noticed that the coupling hub on my idler shaft was quite short, and the end was closed, so it can’t go on too far.

My idler shaft is in pristine condition, and the inner race of a bearing appeared to be mounted on that same diameter. Which says to me that the shaft-diameter tolerance should be well under 0.001”.

My Mark V is a 2005 vintage machine, and I seem to recall that yours are somewhat older, so I have a hunch that Shopsmith changed the shaft diameter to 16 mm (.630”) at some point. I’ll measure the OD with a micrometer tomorrow. Does anyone else with a newer machine know if your chucks and arbors will fit onto your idler shaft?

It does not have to be any longer than the recess in the coupler. So it has a shoulder so it remains on the end of the shaft. If you could put it on far enough that the shaft protrudes through the coupler it will not mate up to the coupler.

I seriously doubt all this. SS has not changed the spindle diameters since the first 10E in 1947.

If SS did not want you to mount a certain adapter (chuck?) on the aux spindle they certainly would not have made a longer hole so that it touched the vent plate.

Pristine spindle or not something else is wrong.

My wife went to bed early, so I went down to the shop and took more measurements, and then did a little bearing-fit research. Now I don't know what to think.

The shaft miked out at 0.6263". My Mitutoyo dial calipers agreed, to the limit of their resolution. I also used the calipers to feel for any diameter changes along the length of the shaft, but couldn't detect any.

I inspected for any burrs or dings, and found none.

So next, I tried mounting: 3 Shopsmith drill chucks, 5 assorted modern Shopsmith arbors, one Ruth Niles bottle-stopper arbor for Shopsmith, and two Shopsmith faceplates. Of all these, only one would even start on the shaft. The exception was a Jacobs 3326 chuck that came with a 10 ER. It would start on, but not go on fully, so it must be a bit bell-mouthed. My other 3326 chuck wouldn't start on at all.

As you can see in the photo below, there is a bearing on that shaft. According to SKF bearing-fit tolerance tables, 0.6263" is too large for a 5/8" ID bearing. For a shaft of this diameter, the largest allowable positive shaft-diameter deviation for any bearing-fit class is 0.0008".

Idler shaft.JPG (391.13 KiB) Viewed 18736 times

The bearing seal is definitely riding on the 0.6263" shaft diameter. I suppose it's possible that beyond the seal, the shaft steps up to fit a 16 mm bearing, but I've never heard of a bearing being configured that way.

As a practical matter, it really doesn't matter, as long as that idler-shaft bearing doesn't fail prematurely. This is the first time that I've tried to use that shaft for anything other than driving my jointer in the usual manner. But it sure does seem odd.

[dusty]

I can add nothing to this thread other than confusion. I did not measure the shafts but I fit six SS hubs (2 different styles) onto both shafts of two machines (Mark Vs) and on the Power Station. They all "slipped" right on if the set screw was retracted.