Mk VII inventory, investigation, and tests

[cham-ed]

I know the 33B jacobs is a standard and in past years you could get a rebuild kit which also fit the 3326

[docmirror]

Whew, Nailed this subject.

[chapmanruss]

docmirror,

You said

Whew, Nailed this subject.

You would think so, right? Well, I still am not sure when the Drill Chuck supplied with a new Shopsmith changed from the Jacobs 3326 to the Jacobs Multi-Craft Chuck. When that occurred makes a difference in which chuck has both the 27100 and 505633 part numbers. Last night I was thinking about this while trying to fall asleep. Then it came to me, JPG may have the answer if he remembers which Drill Chuck came with his Mark 5 Goldie when new. If it was the Jacobs Multi-Craft Chuck that would have them being shipped with new Mark 5's as early as the beginning of 1963. The part numbers changed at the beginning of 1964.

[JPG]

Yep I got a Multicraft chuck. The MVII also came with a multicraft chuck. I have both versions(with/without the model#???). Not sure which is which?? Will take a gander at them and see if I can tell.

Well "maybe". I have three MC8K26 chucks. One from M5, one from MVII and one from ???(bought off e-bay). All three have part# engraved, but the one I believe was sourced on E-bay has the part # engraved on the nose instead of the sleeve.

[chapmanruss]

Thanks, JPG. That, I believe answers the question as to when the Drill Chuck changed from the Jacobs 3326 Chuck to the Jacobs Multi-Craft Chuck. Now I need to correct my information on Drill Chucks including a new picture. I believe the Multi-Craft Chuck with engraving on the nose is the second one.

[CJWigster]

Good day everybody, I have an Old Mk VII and I am rebuilding the headstock. I have all the bearings replaced and it is nice and smooth. But the Drive Coupler seems to be out of tolerance a little bit causing end play on the quill splndle. Is there any way to order this part? Shopsmith of course does not have parts that are compatible they say. And will the shopsmith double bearing quill fit? Or is the shaft different? The drive itself is the newer spline type. Forgive me I don't know what it is called? Thanks!

[JPG]

The quill shaft splines are the same as M5/M7, but is shorter. IIRC the quill body is the same.

Not sure I would cut a new two bearing quill to fit.

"End Play" in/out or side to side wiggle? End play can be adjusted out.

By drive coupler you referring to the quill splined shaft to drive sleeve coupler?? I believe the same as M5/m7.

[Gigs]

"End Play" in/out or side to side wiggle? End play can be adjusted out.

Is there a post on this? If so I'd appriciate being informed about it, Thanks

[DLB]

Good day everybody, I have an Old Mk VII and I am rebuilding the headstock. I have all the bearings replaced and it is nice and smooth. But the Drive Coupler seems to be out of tolerance a little bit causing end play on the quill splndle. Is there any way to order this part? Shopsmith of course does not have parts that are compatible they say. And will the shopsmith double bearing quill fit? Or is the shaft different? The drive itself is the newer spline type. Forgive me I don't know what it is called? Thanks!

The inner bearing in a two bearing quill (current version) doesn't do much for axial spindle end play or axial thrust. IMO. The outer race does not have a seat in the barrel of the quill and is not a very snug fit. So the bearing will just slide in and out along with the spindle unless the outer bearing is preventing it. That is not a criticism of the design, it would take extremely tight tolerances or a different design to provide seats for two bearings in both directions. I think the inner bearing has more to do with runout and extending the life of the Mark 5/V/7 Drive and Ring. Plus marketing. I rebuilt two of these recently with excessive axial end play, both had a bad outer bearing and neither had a bad inner bearing. On one of them I drilled and tapped three holes in the barrel for setscrews to lock that inner bearing outer race in position so that it could share in the axial load (thrust) workload and maybe improve end play.

- David

[JPG]

"End Play" in/out or side to side wiggle? End play can be adjusted out.

Is there a post on this? If so I'd appriciate being informed about it, Thanks

That knurled collar presses against the inner race of the quill bearing. By pulling out on the quill shaft while also pushing in the collar will remove any play between the bearing and the collar. You may be stuck with any play in the bearing itself.