Cast Iron Pulleys - Quality Differences?

[Allan Speers]

I've used Masko (Baldor) brand CI pulleys for multiple projects. They are heavier castings and have better machining than the Grizzly ones (DAMHIKT). My machinist buddy was very impressed with their quality! I buy them from Electric Motor Site at very reasonable rates. They are also very helpful and quick to ship from Wisconsin. They have split taper pulleys starting at about $20 for 3" pulley and taper bushing. They also have step pulleys up to 5 steps. I've ordered from them several times and would suggest them to friends here.
http://www.electricmotorsite.com/

This sounds good, Dick, thanks. I think I'll give these guys a call & run all this by them, then see what they suggest.

- Pretty interesting responses, I must say! What a bloody complicated subject, and we aren't even discussing pulleys!

[Dick Strauss]

Allan,
One thing to note is that the Maska/Baldor pulleys are painted blue and they run true to size for the inner metal diameter. However, that nice blue paint tends to get in the inner diameter and needs to be cleaned out before the pulleys will install properly. You can use sandpaper threaded through a slot cut in a dowel mounted in a drill to quickly clean it out.

God luck,
Dick

[Allan Speers]

I'm still a bit flummoxed.

I see Browning "H" type sheaves, and the description says "uses H style split bushings." They look just like the "P1" bushings, except 4 holes instead of 5 holes. Correct?

Are the P1 bushing superior? - Maybe easier to remove, or something?

[Allan Speers]

There is a sleeve with a very slight taper that slips onto the shaft. It is slit so that when the sheave with matching taper slips over it and gets tightened to the sheave with bolts, the inner taper grips the shaft tightly and the sheave is centered very accurately so that it runs with zero wobble. There are options to fit different motor shafts, including standard sizes and keyways.

Clarification needed:

I understand how a "Taper Lock" bushing works, and this sounds like what JR is describing.
The cap screw tightens the whole bushing, around the shaft, instead of actually contacting the shaft itself, and because it's tapered, this maintains a concentric, even mount as it's tightened. However, Browning doesn't use this type of bushing, at least not with the 2AK41.

The Browning "P1" and "H" split-taper bushings (with the external flange) don't appear to be tapered. - but are they?

There's also a "QD" bushing, which also appears to be different from Browning's split taper design.



note: My head has long since exploded, so now we are just cleaning up the mess.

[Allan Speers]

Sorry for the "BUMP" guys, but I really need to get answers to those last questions of mine. (Both here and on the "V-belts" thread.)


1: Basically, is there any advantage to using an "A" sheave with a "P1" bushing (5 holes) vs an "AK" sheave and the smaller, 4-holed "H" bushing?

I will likely be using AX belts. (I guess.)

-----------

2: I'm also considering changing my planer's arbor pulley instead of the motor pulley: The motor pulley I have now is a little large, but instead of replacing it with the correct 3.95 O.D. sheave, I could replace the 2.7" arbor pulley with one at about 3.4" and get the same ratio. This would give better grip and less bend to the belts. There does seem to be room on the PM 100 arbor for the larger pulley.

Does this make sense, or is it better to stay stock, and assume that "a little slippage under overload conditions" is actually a good original design point?

------------

3: In keeping with #2, could it actually be a BAD idea to use cogged belts, (not ENOUGH slippage) and maybe better to use regular A belts but with the wider arbor pulley?

[John Lanciani]

Have you thought that there is a reason that you're not getting much help with this? It's a wood planer (and a relatively small, crude, and simple one at that), not the space shuttle. Put Browning or Martin sheaves on it with Gates A or AX belts and run it. Really, just do it and be done and move on.

[Allan Speers]

Have you thought that there is a reason that you're not getting much help with this? It's a wood planer (and a relatively small, crude, and simple one at that), not the space shuttle. Put Browning or Martin sheaves on it with Gates A or AX belts and run it. Really, just do it and be done and move on.

That's an odd response, John.

Knowledge is a beautiful thing, and these answers would apply to all machines, so anyone doing future research has this as a resource. Geeez...

And say, you're not seriously calling a PM100 a "crude" planer, are you? It's the 2nd best small planer ever made.

[Dennis Aspö]

I just turned a plywood pulley today for my combo jointer / planer when installing a new motor (made around ww2, so quite modern). Works real well, and I didn't have to spend a dime, just made it from leftover pieces.

[David Kumm]

Allen, I think the point is that these hobby machines don't really stress pulleys to the point where the type of lock system makes much mechanical difference. The ease of assembling and removing them is what I prefer the taper lock for. The bore and set screw is just a huge PITA to deal with so any alternative is way better. Dave

[John Lanciani]

...It's the 2nd best small planer ever made.

If it's that awesome just put back on it whatever the factory did and use it. No sense in reengineering the second best planer ever made is there?

[John McBride]

That's an odd response, John.

Knowledge is a beautiful thing, and these answers would apply to all machines, so anyone doing future research has this as a resource. Geeez...

And say, you're not seriously calling a PM100 a "crude" planer, are you? It's the 2nd best small planer ever made.

Agreed. As someone who buys nearly all their tools second hand, I depend on this forum, and others like it, to provide me with the info I need to seek out, procure,modify and maintain my shop. Regardless of a machine's "simplicity" I always want to be using the very best bits and get them at the very best prices. No other place(s) I can think of allow me to research minute like this one. OP, ask away, I'm taking notes on answers you are getting because a table saw overhaul and up grade are in my near future.

[ian maybury]

Allan - you're not going to get exact answers to your questions unless somebody happens along that has hands on in depth familiarity with the machine and parts in question. It's not all that likely. I'm in Ireland, so not at all familiar with Browning stuff...

This is why as on the belt thread some time ago this stuff almost inevitably comes down to either making a direct size for size replacement in acceptable quality product or using maker's parts, or working through the belt and pulley maker's catalogue (most of which are on the web these days) to verify the slection based on RPM, HP torque numbers, fit etc. My advice is to steady up, sit down and do the spade work. Getting this stuff right is often down to familiarity with the detail of the specific situation anyway - it's hard to for generalised recommendations to be optimum.

If you choose to buy cheap Eastern product, then it's likely a roulette job as to whether you get good quality items. Pays your money/takes your pick - because even if you find somebody who had good luck with a given item the next may or may not be the same. You seem settled on Browning or similar, so hopefully that's not an issue.

By and large if a given size of pulley is available from a good maker in two variants (part numbers) to take different types of bushing, then there's probably some detail difference in the bushings (keyway size, set up to mount inboard or outboard on the motor shaft, available shaft diameter range etc) - which may matter in your situation, or not at all. Back to the catalogue to distinguish between them, or ask your supplier, or phone the makers tech support. If however more than one bushing type is made for the same pulley then it's safe to expect that all will handle anything the pulley is capable of in terms of torque, RPM etc.

Taper lock bushings are just a way of avoiding the need for the supplier to bore and cut a keyway in every pulley sold to suit the shaft it's intended for (getting a good fit entails a clearance of likely less than 0.001in in our sizes) - not a simple job since the shaft has to be measured and there's a risk of error in the boring job, and you're left with a bore matched to a specific shaft. Taper locks as they tighten can handle some variation in shaft size (nominal to a few thou under - as in stock shafting), and they lock the pulley tight on to the shaft too maximising the effectiveness of the key and reducing the risk of fretting. (it turns the whole deal into an over the counter stock parts transaction)

Unless you can get to a person or group with proven expertise/ a proven upgrade on the specific machine it's probably best to directly replace the stuff on the machine if it's working well - whether with OEM spares, or equivalents. If the belt is inclined to slip and that's not caused by wear or another problem (and makers may be tempted to sail close to the wind/use marginally sized cheaper pulleys with DIY level machinery) then your larger same ratio pairing may be an option - but it's your call and needs thinking through to ensure no unexpected side effects. e.g. it'll possibly slow the stopping a bit which may or may not matter. For all that they can act as a useful clutch in a crisis, belt drives realistically can't afford to run close to slipping as with even a little wear that risks quickly becoming inability to transmit the required torque...

You mentioned a stuck handwheel on presumably the same machine in another thread. If it's a headless (damaged) socket head set screw deep in a threaded hole in a cast iron hand wheel that's part buried in a hole in the shaft (could it in fact be a roll pin in a cross hole that could be tapped out with a drift?) then there's probably not much choice but to drill it out, and then either helicoil to repair or re-tap the wheel to take a suitably oversized screw. Use a good quality (tough) sharp HSS or better still cobalt drill from a tooling supplier and lowish RPM if it's a set screw, as they are quite tough and can harden dramatically if overheated. Start with a smaller size to get a hole started that's centred in the screw socket. Use a pullers (bearing on the hub of the wheel) to get it off if with the screw removed it's still very tight on the shaft. If the parts get destroyed then it's buy new stuff as needed - there's no guarantees...

[Ronald Blue]

Here is a link to Grainger for a taper lock pulley and bushing set up. They really are a quality setup and will run for many years without any issue.
grainger.com/content/general-catalog?pagelabel=150&search=1NHX2 You don't have to get it here but it's good reference material. Just add the www to the front to make the link work.

[Michael W. Clark]

Another reason bushings are used is to eliminate press fits. A sliding fit will not handle the amount of torque that a press fit does. However, if you press fit, field removal requires heating with a torch for removal and is not always doable depending on the location. It's rare that the sheaves need to be replaced unless the speed needs to be changed. Bushings on the motor shaft are nice because they make replacing the motor in the field much easier in regards to swapping the sheave to the new motor.

Allan, I would take detailed measurements of everything and go talk to an industrial power train distributor. I think you will end up with better quality set screw sheaves. This is a fairly light application for the components you are considering.