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Re: Upper and lower output drive shafts slightly different sizes

Posted: Sun Jan 26, 2020 2:46 pm
by JPG
almackovjak wrote:Thank you JPG, I am considering how to remove material from shaft or bore of hub. Steel wool, scotchbrite, emery cloth, ream an extra hub to fit, are good ideas but how would it be done with any degree of accuracy? It seems that I would need to take the .632" shaft down to approximately .626" which is not an insignificant amount of steel. Thanks again for your input!
It can be done but requires patience. Emery cloth(strips) would be my choice. Care needs to be exercised so as to make the reduction distributed equally along the shaft axis. Using flat strips can help with that. Measure often and everywhere so as to allow compensating pressure.

I do not think reaming a hub is addressing the actual problem.

I would shoot for 0.624.

Re: Upper and lower output drive shafts slightly different sizes

Posted: Sun Jan 26, 2020 3:48 pm
by P89DC
Is the end of the shaft peened from previous owner abuse? I've had that issue twice on rebuilds. I ran the headstock and used Emery cloth on a flat file to take the burr off and all is well.

Re: Upper and lower output drive shafts slightly different sizes

Posted: Sun Jan 26, 2020 4:45 pm
by almackovjak
Thanks folks. I will speak with Shopsmith tomorrow and try to figure out a solution. I believe I need to verify the sizes of the bore on the upper and lower power coupler hubs (particularly the drive hubs having four splines) and maybe purchase a new set. You have all been very helpful, thank you.

Re: Upper and lower output drive shafts slightly different sizes

Posted: Mon Jan 27, 2020 6:20 pm
by almackovjak
Thanks for this information. The Shopsmith site does not list the bore size on these output hubs. I called them today and they promised to get back to me. I have seen the closed output hubs, I believe designated for the lower shaft, but I have heard of those being one-half inch bore size. If, like you mentioned, the upper and lower hubs have around 5/8" bores, then I guess the next step is to try another 5/8" lower hub. Why would Shopsmith have a hard time with the question "what is the bore size of the upper and lower output hubs?"

Re: Upper and lower output drive shafts slightly different sizes

Posted: Mon Jan 27, 2020 6:37 pm
by rpd
almackovjak wrote:Thanks for this information. The Shopsmith site does not list the bore size on these output hubs. I called them today and they promised to get back to me. I have seen the closed output hubs, I believe designated for the lower shaft, but I have heard of those being one-half inch bore size. If, like you mentioned, the upper and lower hubs have around 5/8" bores, then I guess the next step is to try another 5/8" lower hub. Why would Shopsmith have a hard time with the question "what is the bore size of the upper and lower output hubs?"
I would suspect the actual bore size is a bit larger than 5/8, to allow for a slip fit..

Re: Upper and lower output drive shafts slightly different sizes

Posted: Mon Jan 27, 2020 7:19 pm
by JPG
[quote="almackovjak" . . . Why would Shopsmith have a hard time with the question "what is the bore size of the upper and lower output hubs?"[/quote]

Because CS are not part of the engineering department, are fairly new employees, are likely still wet behind the ears, and may have been instructed to not answer that kind of question(for that kind of information, engineering must get involved - for a price).

Yes it is male bovine merde.

Regardless the hubs fit onto a 5/8" shaft.(at least that is what it is supposed to be).

BTW The hub bore size is not the right question. Rather what is the shaft od?