Page 4 of 5
Re: Idler shaft bearing on the Power Pro???
Posted: Sat Mar 07, 2020 6:05 pm
by reible
I haven't looked at the link reference above but I have done two of these kits and I didn't have any issue understanding the section of the manual dealing with Balancing the Belt Tension.
That is part of the Maintenance and Troubleshooting in the manual they sent me. Pages starting at E1 through E4.
Do those of you having problems have that section to look at?
One of my machines has been very stable since the start, the other has required a couple belt adjustment but now seems to have stabilized. The issue appeared as slipping of the upper belt.
Now I don't often use the higher speeds, saw speed or below are the majority of the time and I have not seen the bearing issues yet, possible because of that.
I have not seen the pulley coming loose either, again that might be more of how I use my machines.
Historically some machines have had some issues while others like mine just keep ticking along. I really do like the powerpro and while I can think of a few things that I wish were differenct, like I wish the speed range was 100 to say 5000 and I wish it had a remote switch.... and well that is about it.
Ed
Re: Idler shaft bearing on the Power Pro???
Posted: Sun Mar 08, 2020 5:05 pm
by rjent
JPG wrote:rjent wrote:godavid2 wrote:Thanks Dick, did you replace the set screw and key too?
Actually, I did not. Didn't know about the other set screw. I will take the cover back off in a few days to check on things (on this maintenance free machine LOL) and will check that out.
Want to share the troubleshooting link?

Sometimes it is best to let sleeping dogs lie.

In other words, don't fix it if it ain't broke

Re: Idler shaft bearing on the Power Pro???
Posted: Sun Mar 08, 2020 5:11 pm
by rjent
reible wrote:
Now I don't often use the higher speeds, saw speed or below are the majority of the time and I have not seen the bearing issues yet, possible because of that.
I have not seen the pulley coming loose either, again that might be more of how I use my machines.
I think that is possibly why you haven't had any problems. As I said, that shaft runs at 16K at 10000 RPM quill speed. My guess is that the bearings are just too light for the loads and speed.
I started having set screw/pulley problems when using the band saw. This problem has been covered in other threads. I didn't catch the loose pulley until damage was done. I don't use the bandsaw on the powerpro anymore. Glad I have other machines to mount it on ....

Re: Idler shaft bearing on the Power Pro???
Posted: Sun Mar 08, 2020 6:58 pm
by BuckeyeDennis
rjent wrote:reible wrote:
Now I don't often use the higher speeds, saw speed or below are the majority of the time and I have not seen the bearing issues yet, possible because of that.
I have not seen the pulley coming loose either, again that might be more of how I use my machines.
I think that is possibly why you haven't had any problems. As I said, that shaft runs at 16K at 10000 RPM quill speed. My guess is that the bearings are just too light for the loads and speed.
I started having set screw/pulley problems when using the band saw. This problem has been covered in other threads. I didn't catch the loose pulley until damage was done. I don't use the bandsaw on the powerpro anymore. Glad I have other machines to mount it on ....

Do you have a speed reducer, Dick? Someone, I think maybe charlese, reported that installing the speed reducer between the PP headstock and the bandsaw eliminated the problem. That makes perfect sense to this old motion-control engineer, but I’ll spare you the eye-glazing reasons why.
Re: Idler shaft bearing on the Power Pro???
Posted: Sun Mar 08, 2020 8:51 pm
by jsburger
BuckeyeDennis wrote:rjent wrote:reible wrote:
Now I don't often use the higher speeds, saw speed or below are the majority of the time and I have not seen the bearing issues yet, possible because of that.
I have not seen the pulley coming loose either, again that might be more of how I use my machines.
I think that is possibly why you haven't had any problems. As I said, that shaft runs at 16K at 10000 RPM quill speed. My guess is that the bearings are just too light for the loads and speed.
I started having set screw/pulley problems when using the band saw. This problem has been covered in other threads. I didn't catch the loose pulley until damage was done. I don't use the bandsaw on the powerpro anymore. Glad I have other machines to mount it on ....

Do you have a speed reducer, Dick? Someone, I think maybe charlese, reported that installing the speed reducer between the PP headstock and the bandsaw eliminated the problem. That makes perfect sense to this old motion-control engineer, but I’ll spare you the eye-glazing reasons why.
Speaking of charlese, does anyone know what has happened to him. He hasn't posted in a long time.
Re: Idler shaft bearing on the Power Pro???
Posted: Sun Mar 08, 2020 10:09 pm
by JPG
I hope my recent thoughts about that are inaccurate!!
Re: Idler shaft bearing on the Power Pro???
Posted: Mon Mar 09, 2020 7:45 am
by rjent
BuckeyeDennis wrote:rjent wrote:reible wrote:
Now I don't often use the higher speeds, saw speed or below are the majority of the time and I have not seen the bearing issues yet, possible because of that.
I have not seen the pulley coming loose either, again that might be more of how I use my machines.
I think that is possibly why you haven't had any problems. As I said, that shaft runs at 16K at 10000 RPM quill speed. My guess is that the bearings are just too light for the loads and speed.
I started having set screw/pulley problems when using the band saw. This problem has been covered in other threads. I didn't catch the loose pulley until damage was done. I don't use the bandsaw on the powerpro anymore. Glad I have other machines to mount it on ....

Do you have a speed reducer, Dick? Someone, I think maybe charlese, reported that installing the speed reducer between the PP headstock and the bandsaw eliminated the problem. That makes perfect sense to this old motion-control engineer, but I’ll spare you the eye-glazing reasons why.
No, I don't have a speed reducer and don't seem to need one, but I have two other 500's that I have my bandsaw(s) mounted to, so it is all good. No problems with running them that way.

Re: Idler shaft bearing on the Power Pro???
Posted: Mon Mar 09, 2020 7:54 am
by dusty
If I have missed something while reading this thread, please excuse me but has anyone talked with Shopsmith about the possibility that the Power Pro Idler Shaft bearings might be under rated for the speed range of the Power Pro?
Has anyone done any research to determine what the recommended max RPM is for the bearings (6903RS) that are being used?
http://www.vxb.com/v/vspfiles/catalog/d ... 044_1.html
NOTE: The spec sheet is for bearings by VXB which might not be the ones used by Shopsmith.
Re: Idler shaft bearing on the Power Pro???
Posted: Mon Mar 09, 2020 9:04 am
by BuckeyeDennis
dusty wrote:If I have missed something while reading this thread, please excuse me but has anyone talked with Shopsmith about the possibility that the Power Pro Idler Shaft bearings might be under rated for the speed range of the Power Pro?
Has anyone done any research to determine what the recommended max RPM is for the bearings (6903RS) that are being used?
http://www.vxb.com/v/vspfiles/catalog/d ... 044_1.html
NOTE: The spec sheet is for bearings by VXB which might not be the ones used by Shopsmith.
Excellent point, Dusty.
The link you provided gives a "Limiting Speed" of 15,000 RPM. If the idler shaft runs at 16,000 RPM, that could certainly be a problem. A Google search turned up the following definition of "Limiting Speed":

- Capture.JPG (31.5 KiB) Viewed 11271 times
But as you point out, we don't know if that VXB bearing is an exact equivalent. I know for a fact that OEM's
can order bearings with special greases and seals that enable operation at somewhat higher speeds.
Re: Idler shaft bearing on the Power Pro???
Posted: Mon Mar 09, 2020 12:34 pm
by godavid2
Update, just got off the phone with SS and was told the idler shaft bearings were rated for high speed. SS is sending me another motor pulley and set screw was told to be sure to use blue locker and keep the pulley next to the retaining ring.