Speed changer handle came off...now what?

[jalex7672]

Hey guys! I got the problem fixed!
Several things helped out, the help from all of you first and foremost!
Remembered that where I work, we had recently purchased a laser optical tachometer. Brought it home this evening, set it up, and was reading 6500 RPM's!!! Like I said, it was screaming. Dialed it down, removed the set screw stop for the Fast speed adjustment. Something JPG said made my mental gears start turning... the length of the set screw being 1 1/8". Mine measured 1". Went to local Ace Hardware, knowing I wouldnt find a set screw that long, but came up with something just as good. Found a button-head screw that is 1/4-20 thread same as the set screw, 1" long. It also takes a 5/32" allen wrench. Brought it home, screwed it in and was reading about 1450 RPM's, so carefully ground down the tip of the screw and re-installed, ran up to Fast, and re-tached the arbor. Re-ground length as needed until I got down to 5205 RPM's with it screwed all the way in and torqued. This fix eliminated the set screw as well as the jam nut, as the button head seats on the bushing under the gear, and also prevents the gear from coming off. And you can use the standard 5/32" allen wrench to install and remove it. My belt is riding 3/32 below the rim of the drive variator pulley.
I will take some pics and try to post on here.
The belt "fuzzing" on the motor side still has me concerned a bit, and I do feel I should order a new belt. The fuzzing isnt terribly bad, but I do feel I need to get one coming.
I hear the belts from Shopsmith are taking forever to ship. Does anyone know a source? I see ads on Ebay for Shopsmith belts... can they be trusted?
By the way, Thank for the offer of driving down here from Columbus, Ron! Its sure nice to know there are such good people on here who are so willing to help!
Oh, and to answer a previous question, I had thoroughly cleaned and lubed the entire machine approximately 1 hour running time prior to all this.
Thanks again for all your help guys!:)

[Ron309753]

Jalex,

See Bill Mayo's post in this thread:
http://www.shopsmith.net/forums/showthread.htm?t=3841&highlight=Powertwist

I think you can get Powertwist belt sections at the WoodCraft store in Columbus. You can also order them online from numerous sources.

Sincerely,

Ron309753

[JPG40504]

Hey guys! I got the problem fixed!
Several things helped out, the help from all of you first and foremost!
Remembered that where I work, we had recently purchased a laser optical tachometer. Brought it home this evening, set it up, and was reading 6500 RPM's!!! Like I said, it was screaming. Dialed it down, removed the set screw stop for the Fast speed adjustment. Something JPG said made my mental gears start turning... the length of the set screw being 1 1/8". Mine measured 1". Went to local Ace Hardware, knowing I wouldnt find a set screw that long, but came up with something just as good. Found a button-head screw that is 1/4-20 thread same as the set screw, 1" long. It also takes a 5/32" allen wrench. Brought it home, screwed it in and was reading about 1450 RPM's, so carefully ground down the tip of the screw and re-installed, ran up to Fast, and re-tached the arbor. Re-ground length as needed until I got down to 5205 RPM's with it screwed all the way in and torqued. This fix eliminated the set screw as well as the jam nut, as the button head seats on the bushing under the gear, and also prevents the gear from coming off. And you can use the standard 5/32" allen wrench to install and remove it. My belt is riding 3/32 below the rim of the drive variator pulley.
I will take some pics and try to post on here.
The belt "fuzzing" on the motor side still has me concerned a bit, and I do feel I should order a new belt. The fuzzing isnt terribly bad, but I do feel I need to get one coming.
I hear the belts from Shopsmith are taking forever to ship. Does anyone know a source? I see ads on Ebay for Shopsmith belts... can they be trusted?
By the way, Thank for the offer of driving down here from Columbus, Ron! Its sure nice to know there are such good people on here who are so willing to help!
Oh, and to answer a previous question, I had thoroughly cleaned and lubed the entire machine approximately 1 hour running time prior to all this.
Thanks again for all your help guys!:)
Wonder who installed a 'shorter screw'?

Glad the 'mystery' is solved!!!!! It had me scratching my head!!

BTW the part number is 51398905. You oughta get one the next time you order from ss. ($0.80)

[dusty]

OR, As I believe is correct for this scenario, What makes it a 'jam' nut is how it is used, not due to any of its physical properties. In this case, the nut is tightened against an opposing set of threads(the casting) so as to lock the screw in position.??An opposing set of threads?? Are the threads in the casting different than the threads in the nut?

Does "opposing" mean left hand versus right hand threads?

[JPG40504]

??An opposing set of threads?? Are the threads in the casting different than the threads in the nut?

Does "opposing" mean left hand versus right hand threads?
Opposing as in resisting advance of the nut farther towards the surface of the solid object which contains the opposing thread. Tightening the jam nut against that surface causes the screw thread to be pulled against the thread surface closest to the surface thus removing any play(clearance) between the mating threads. The same is occurring between the screw thread and the nut.

In the case of the speed control, a spacer is between the nut and the the casting surface. This spacer leaves enough clearance between the jam nut and the gear which rotates on the spacer. The nut prevents the gear from slipping off the spacer.