Sourcing motor pulley

[Patrick Kane]

I need a motor pulley for my PM72. Unfortunately, this is proving to be slightly more difficult than I anticipated. I need a 4 v belt pulley with 3” outside diameter, 7/8” bore, and 1.75” wide. All I seem to find are pulleys with indeterminate bores. They don’t spec out the total width either.

https://m.grainger.com/mobile/product/TB-WOOD-S-Quick-Detachable-Bushed-Bore-WP9198843/_/N-hxdZ1yzy5f0Z1yzavsq?R=5YKT1&breadcrumbCatId=5260&fromPidp=true&picUrl=%2F%2Fstatic.grainger.com%2Frp%2Fs%2Fis%2Fi mage%2FGrainger%2F10Y267_AS01%3F%24smthumb%24webpa rentimage%24

is this typical? I’m guessing I can get a bushing to get the bore to fit 7/8, but how do I ensure it’s properly sized to fit the shaft key. This also seems a little janky. Anyone have a better source?

[Dan Friedrichs]

Hopefully someone smarter than me will comment, but I've had this problem, too.

If I understand, the combination of pulley diameters and bore diameters makes for such an intractably large number of combinations that they sell "quick connect" bushings to mate a given shaft to a given pulley. For the pulley you linked, you need a compatible quick-disconnect bushing:
https://www.mcmaster.com/pulley-bushings

[Andrew Hughes]

Try this place Patrick https://electricmotorwarehouse.com/pulleys-sheaves/
They have a good selection. I don’t envy you it’s not easy swapping motors and figuring out all the speeds and belts.
For me it wasn’t :(

[Darcy Warner]

Buy one that is not bored. I will have to look up the place I buy from. Able to find just about any obscure/odd sized pulley, have it bored to what i need and a key way broached.

[Ken Fitzgerald]

Patrick,

The one Grainger is displaying is by TB Woods. Here you can download their catalogue and it has the information for which you are asking, IMO. https://www.tbwoods.com/products/belted-drives/Sheaves-and-V-Belts/Narrow-Ultra-V-Sheaves-and-V-Belts Go to "Literature" to download the catalogue.

[Mark Paavola]

How about this one from Graingers.

WOOD'S 7/8" Fixed Bore Variable Pitch V-Belt Pulley, For V-Belt Section: 3L, 4L, 5L, A, AX, B, BX Item # 5UHR2
Mfr. Model # 1VP3478

[lee cox]

I could not find a pulley for my old Atlas drill press spindle shaft. I bought a pulley close and had a machine shop enlarge the pulley on a lathe. That was several years ago. I thought about drilling it but I was afraid it would end up a little off center.

[Wayne Lomman]

Any half reasonable bearing supplier carries pulleys as well. Ask for the diameter you need with a taper lock to suit your shafts size. A taper lock is a centre bush that will clamp to your shaft. Only tools required are Allen wrenches. Taper locks and pulleys sold separately so you can get the combination you need. Just finished doing this on the 10000cfm dust collector that was eating belt sets due to worn pulley grooves. Cheers

[David Kumm]

If the design allows it, taper lock is the way to go. Dave

[John Patric]

Jason Industrial makes an adjustable link v-belt. I think it is available on Amazon.

[Tim Einwalter]

I need a motor pulley for my PM72. Unfortunately, this is proving to be slightly more difficult than I anticipated. I need a 4 v belt pulley with 3” outside diameter, 7/8” bore, and 1.75” wide. All I seem to find are pulleys with indeterminate bores. They don’t spec out the total width either.

https://m.grainger.com/mobile/product/TB-WOOD-S-Quick-Detachable-Bushed-Bore-WP9198843/_/N-hxdZ1yzy5f0Z1yzavsq?R=5YKT1&breadcrumbCatId=5260&fromPidp=true&picUrl=%2F%2Fstatic.grainger.com%2Frp%2Fs%2Fis%2Fi mage%2FGrainger%2F10Y267_AS01%3F%24smthumb%24webpa rentimage%24

is this typical? I’m guessing I can get a bushing to get the bore to fit 7/8, but how do I ensure it’s properly sized to fit the shaft key. This also seems a little janky. Anyone have a better source?

I have a hunch that I just went through this for a 12/14 saw. My specs were 8" diameter, 4 groove, A belt with a bushing for 1.125" shaft. Super easy. Wrong! Totally unobtainable. It turns out that everybody uses an A-B belt design nowadays which pushes the belts further apart. Basically the width of an A-B pulley is greater than an A only pulley. I ended up getting a custom pulley quote and to buy a new motor would be cheaper. I'm not sure where you are located, but I have a nice bearing supply store close to me. I take my specs in to them and, if it's available, they can get it for me.

[Tom M King]

There is a seller on ebay that sells all sorts of pulleys, even in different quality grades.

[David Kumm]

Tim, can both pulleys be replaced? With today's belts you don't need four, two would likely be fine. Dave

[Bill Dufour]

If the design allows it, taper lock is the way to go. Dave
Absolutely. Buy the sheave to match then the taper hub to match the shaft. Note that there are several standard taper hub sizes so the pulley and hub have to match. there is some overlap but you have to know they will match.
Bil lD

Tractor supply has weldable hubs and sprockets I do not think they have weldable pulleys.

[Bill Dufour]

How many HP? how small is smallest pulley? seems like two belts should be enough. My 3HP Unisaw I am only using two belts it is designed for three.
Bill D

[Don Jarvie]

3 belts is plenty. Swap out both the motor and arbor pulley. It will be easier to find a 3 belts for swapping out both.

[Patrick Kane]

Didnt even think to go to the bearing shop. I have a handful locally, and ill go that route.

Going for 5hp motor. Yes, i did consider swapping out the arbor pulley to match the new motor pulley, but thought it might be simpler to just find the right motor pulley. Most modern drives use one wide belt instead of numerous v belts anyways, right?

Glad im not the only one that has struggled with this. Already ive been proven wrong on sourcing a lot of parts for this powermatic.

[Don Jarvie]

I get my pulleys and belts at Surplus Center. It’s easier to swap out both pulleys since you can get the same pulley with the different bores. 3 belts is much harder than 2 so I would recommend 2 belts. 2 belts is plenty for a 5 hp motor. I would need to look at what I did for my 66 but a 3 1/2 wide pulley would fit.

[Malcolm McLeod]

I get my pulleys and belts at Surplus Center. It’s easier to swap out both pulleys since you can get the same pulley with the different bores. 3 belts is much harder than 2 so I would recommend 2 belts. 2 belts is plenty for a 5 hp motor. I would need to look at what I did for my 66 but a 3 1/2 wide pulley would fit.

Careful with broad sweeping statements.;) Horsepower transmission for a given sheave (pulley)>v-belt>sheave combination is dependent on several factors: smallest diameter, rpm, v-belt profile, allowable tension, and # of belts primarily, but there are others. Most catalogs for any specific manufacturer will have a design guide included. I highly recommend them!!

There are numerous versions of the 'Taper Lock' concept, including a trademarked one. Also search for 'QD bushing'. If memory serves, Martin, Dayton, Gates, and TB Woods are the big names. If you ever want to change a drive ratio, they are the way to go: keep the hub, and just buy a new sheave diameter. The hubs are designed/sized to fit standard frame motors and common shafting sizes.

If you never expect a speed change, then a pre-bored sheave may be cheaper - - if you find the right size. I'd suspect a machine shop's time to custom bore it will double or triple your costs?

[Darcy Warner]

As an example, I needed a motor pulley that was roughly 5 1/4" OD, 4 groove, A series belts with a 32mm bore.
After two failed tries by motor shop, I found a supplier on line that had 4 groove A series pulleys in the exact size I needed. 145.00 for the pulley and 70 bucks to bore and broach and I had the exact pulley I needed. My only other option was having one made, last odd ball 2 step pulley i had made was 400 bucks.