Drive hub for Speed Reducer

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scollins
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Location: Chapel Hill, TN

Drive hub for Speed Reducer

Post by scollins »

Apparently, I have lost the drive hub for my Speed Reducer. Does anyone have a part number for it? It needs to fit the 5/8" shaft on the quill. I have several drive hubs for this shaft, but the notches do not line up with the coupler in the reducer. The drive hub for the jointer has the correct spacing on the notches but is a 1/2" shaft.
edma194
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Re: Drive hub for Speed Reducer

Post by edma194 »

I believe this is the part you are talking about: https://www.shopsmith.com/ownersite/cat ... r_hubs.htm
503570 Upper Headstock Drive Hub ... $6.99

The other hubs you have must be accessory hubs that would fit on SPTs like the bandsaw, belt sander, etc. The speed reducer has a built in accessory hub unlike those tools.
Ed from Rhode Island

510 PowerPro Double Tilt:Greenie PowerPro Drill Press:500 Sanding Shorty w/Belt&Strip Sanders
Super Sawsmith 2000:Scroll Saw w/Stand:Joint-Matic:Power Station:Power Stand:Bandsaw:Joiner:Jigsaw
1961 Goldie:1960 Sawsmith RAS:10ER
scollins
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Location: Chapel Hill, TN

Re: Drive hub for Speed Reducer

Post by scollins »

Thanks, but can't tell if that is the right part. The drive hub that goes in the SR coupler is a midge smaller and the notches are spaced differently.
br549
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Re: Drive hub for Speed Reducer

Post by br549 »

I purchased part no. 503740 in 2011 for mine.
edma194
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Re: Drive hub for Speed Reducer

Post by edma194 »

br549 wrote: Tue Aug 02, 2022 1:03 pm I purchased part no. 503740 in 2011 for mine.
That's listed as an accessory hub for an SPT, but I'm never sure what they mean with those names. I'm sure chapmanrusswill come along and set me straight. In the mean time I'll go look at mine.
Ed from Rhode Island

510 PowerPro Double Tilt:Greenie PowerPro Drill Press:500 Sanding Shorty w/Belt&Strip Sanders
Super Sawsmith 2000:Scroll Saw w/Stand:Joint-Matic:Power Station:Power Stand:Bandsaw:Joiner:Jigsaw
1961 Goldie:1960 Sawsmith RAS:10ER
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chapmanruss
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Re: Drive hub for Speed Reducer

Post by chapmanruss »

Thanks for the vote of confidence Ed.

I hope this can help. I have never owner a Speed Reducer but do have the Speed Increaser. According to the PDF copy of the Speed Reducer manual I have (dated 11-89) it uses the same coupling P/N 515798 (ref. #6) that the Speed Increaser uses. That takes a P/N 503740 5/8" SPT Accessory Hub (ref. #36 in the Speed Reducer Manual) mounted on the spindle. Remember the SPT Hubs have five splines whereas the Headstock Hubs have four splines.
Russ

Mark V completely upgraded to Mark 7
Mark V 520
All SPT's & 2 Power Stations
Model 10ER S/N R64000 first one I restored on bench w/ metal ends & retractable casters.
Has Speed Changer, 4E Jointer, Jig Saw with lamp, a complete set of original accessories & much more.
Model 10E's S/N's 1076 & 1077 oldest ones I have restored. Mark 2 S/N 85959 restored. Others to be restored.
edma194
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Re: Drive hub for Speed Reducer

Post by edma194 »

Thanks Russ. I just looked at my speed reducer and it does have an accessory coupler end. I never noticed, as usual I just find a hub that matches the number of splines. Since it has an integral coupler I thought that would be the equivalent of the headstock end of a coupler.
Ed from Rhode Island

510 PowerPro Double Tilt:Greenie PowerPro Drill Press:500 Sanding Shorty w/Belt&Strip Sanders
Super Sawsmith 2000:Scroll Saw w/Stand:Joint-Matic:Power Station:Power Stand:Bandsaw:Joiner:Jigsaw
1961 Goldie:1960 Sawsmith RAS:10ER
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chapmanruss
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Re: Drive hub for Speed Reducer

Post by chapmanruss »

This had me thinking about the coupler P/N 515798 that both the Speed Reducer and Speed Increaser use. The later Air Compressor made for Shopsmith by Campbell Hausfeld also came with that coupler. When new it included a 5/8" bore SPT Hub for attaching it to the upper drive on the Headstock. Since the shaft of the Campbell Hausfeld Air Compressor is 5/8" diameter you can use the 5/8" SPT Hub on it and a standard power coupler to drive it leaving the normal Drive Hub on the Headstock.

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Coupler on Air Compressor.jpg
Coupler on Air Compressor.jpg (234.16 KiB) Viewed 928 times
Russ

Mark V completely upgraded to Mark 7
Mark V 520
All SPT's & 2 Power Stations
Model 10ER S/N R64000 first one I restored on bench w/ metal ends & retractable casters.
Has Speed Changer, 4E Jointer, Jig Saw with lamp, a complete set of original accessories & much more.
Model 10E's S/N's 1076 & 1077 oldest ones I have restored. Mark 2 S/N 85959 restored. Others to be restored.
edma194
Platinum Member
Posts: 1875
Joined: Fri Jun 19, 2020 4:08 pm

Re: Drive hub for Speed Reducer

Post by edma194 »

The speed reducer doesn't seem like an accessory end to me, it extends the drive shaft to attach other accessories to. But I don't know the reasoning behind the differences in the two types of hubs. Why would 4 splines on the headstock side be preferrable to 5 on the accessory side? They could be keyed in other ways to differentiate the ends. Couplers have to absorb the sudden torque at start up at the headstock end, but jamming is going to hit the accessory end hard, that could be worse than the startup.
Ed from Rhode Island

510 PowerPro Double Tilt:Greenie PowerPro Drill Press:500 Sanding Shorty w/Belt&Strip Sanders
Super Sawsmith 2000:Scroll Saw w/Stand:Joint-Matic:Power Station:Power Stand:Bandsaw:Joiner:Jigsaw
1961 Goldie:1960 Sawsmith RAS:10ER
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chapmanruss
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Joined: Tue Aug 26, 2014 8:16 pm
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Re: Drive hub for Speed Reducer

Post by chapmanruss »

I cannot answer why the Hubs were designed the way they are. That would be a question for the engineers at Magne Engineering Corporation from 1954 when the second version and the predecessor of the current Power Coupler was introduced. Having them different on each end did make a Headstock and Accessory side to them and keeps the safety feature of the spring on the Headstock side.
Russ

Mark V completely upgraded to Mark 7
Mark V 520
All SPT's & 2 Power Stations
Model 10ER S/N R64000 first one I restored on bench w/ metal ends & retractable casters.
Has Speed Changer, 4E Jointer, Jig Saw with lamp, a complete set of original accessories & much more.
Model 10E's S/N's 1076 & 1077 oldest ones I have restored. Mark 2 S/N 85959 restored. Others to be restored.
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