Delta Unisaw #6: Video of it running with/without pulley on

Why are there no belts installed ? Did you have the pulley ballanced ? I think you had mentioned earlier that you were going to. You did replace the bearings right ?

-- If you can't find the time to do it properly, how will you find the time to fix it ?

Belts are not on yet because the saw still vibrates with just the motor and pulley in it. I can’t really check the arbor for vibration until I solve the motor/pulley vibration.

Pulley was balanced and I did have the motor bearings replaced. After all of that, there is no change in the amount of vibration.

The electric motor repair shop and the machinist that balanced the pulley have both suggested that I pull the rotor out of the motor and bring it along with the pulley and key to the machinist to see if he can get them balanced together. Maybe the shaft he balanced the pulley on and my rotor are not balanced the same.

Anyone else have a better idea than that? Or can think of something other than the pulley/rotot being out of balance that would cause the vibration?

Or, am I just being too picky and I need to just use the darn thing?

-- Kevin, Wichita, Kansas

Not that I have any experience with a Unisaw but, shouldn’t the electrical motor shop have made sure the motor was balanced before sending it out the door ? If the pulley is balanced I would doubt that it’s the pulley. I’d try it with the belts on it, maybe that will take care of it. What do you have to lose ? When I asked about if you had the bearings replaced, I meant the arbor bearings. I would still try the belts first before throwing more money at it. Hopefully the belts you have look good and are a matched set.

-- If you can't find the time to do it properly, how will you find the time to fix it ?

Is it possible that the machine shop balanced the pully but not have checked it for roundness? A pully could be balanced for weight- like balancing a lawn mower blade- but if the pully is not a true circle it would create a vibration when running.

Just a thought.

Lew

Does the motor run smoothly by itself sitting on a table or bench or floor without the pulley? If it does, add the pulley and try it. If it still runs smooth, the perhaps your motor mounts, either on the saw or on the motor itself are bent, and when the bolts are tighten the motor is “tweaked”. You may have a bent or cracked motor mount. If it runs smooth without the pulley, is there a square key or bolt that is throwing it out of whack? Can you borrow a motor to test it out and to isolate the problem further?

-- NorthWoodsMan

Lew, I never thought of the pulley being out of round. That is a good point.

NorthWoodsMan, The motor runs smooth while mounted to the saw until the pulley is mounted. I would think that would mean it wasn’t the motor mounts. What do you think?

I haven’t been able to find another motor with a 3/4” shaft to try the pulley on.

-- Kevin, Wichita, Kansas

It sounds like I may be better off buying a new pulley and trying that route after all.

What kind of pulley do you guys suggest/use on your Unisaw? Cast Iron or Steel.

-- Kevin, Wichita, Kansas

Kevin, the only other thing that I can think of- is the pulley actually tight on the shaft when you tighten the set screw? I checked at the site where I buy my Delta parts and the pulley is not available on line from them. I know I’ve seen places that sell after market pulleys, I’ll have to research it tomorrow. good luck.

-- Tim -- http://tmuli.com

The pulley is tight. Atleast I cannot move it back and forth any.

-- Kevin, Wichita, Kansas

I believe you making the right choice with a new pulley Kevin. Always go with steel over cast iron.
If one is available I suggest using a Browning pulley. They are top notch, factory balanced and true.

As an after thought, if your rotor and pulley are balanced together then you will have to replace both if either dies on you. Of course that may never happen but electrical equipment has a thing for burning out.
I never liked cast iron pulleys simply because they are cast. There will always be an “air” pocket somewhere in it.

-- .

BroDave,

You hit the nail on the head with that one. My fear in balancing them both together was that if something happened to either I’d have to replace both.

Can anyone tell me where to order a steel pulley?

The local motor shop doesn’t seem to be able to or doesn’t want to. He tels me that the cast iron is the way to go. Also the local Delta shop says the same thing.

-- Kevin, Wichita, Kansas

Kevin,

Here are a couple of web sites that may help you locate a pulley-

http://www.thomasnet.com/products/vbelt-pulleys-63910806-1.html

http://www.sdp-si.com/eStore/CoverPg/Pulleys.htm?wcw=google&gclid=CPDS3rSzhZICFQWnlgodcQcw_A

The first one has a list of companies that supply pulleys and the second is a specific manufacturer.

Hope this helps,

Lew

If you have a W.W. Grainger local you may find exactly what you need.
I wouldn’t go without pulley and tape measure in hand though, just saying…

-- .

I have looked though Grainger’s online catalog with now luck. Same thing for Thomas net and a few of the others Lew mentioned.

I can find cast iron pulleys, but am still having a hard time finding a steel pulley.

Has anyone ever actually bought one for their saw? Where? How much?

-- Kevin, Wichita, Kansas

I couldn’t find a steel pully but the OEM ones have been used for over 50 years.

The OEM part number for the pully is 41-644.

Ordering directly from Delta will save you a big $2.00

Here is the complete parts list for your saw:

http://www.ereplacementparts.com/delta-36812-type-table-saw-parts-c-3275_3334_3440.html?osCsid=cab09f434de3209956caa4158b468ee5

-- Gary, East TX -- The longest journey begins with a single step.

1939 Units had pot metal triple belts pulleys. Units with 1750 RPM motors had 5.25” diameter drive pulleys which were also pot metal.

19XX units changed to steel machined arbor pulleys. 3450 Motors had smaller 3.25” diameter pulleys that were machined from solid steel. You still haven’t tried it with the belts on it yet ? They tell you to try it with the belts on and no blade.

-- If you can't find the time to do it properly, how will you find the time to fix it ?

Mine is a 3.25” cast iron pulley on a 3450 motor.

-- Kevin, Wichita, Kansas

Gary,

Thanks for the website. If I cannot find a steel one, I’ll order a new OEM one.

That is going to be a helpful website for a few other tools I have.

-- Kevin, Wichita, Kansas

Well Woodchuck, I finally got home from work. Man, working all day sure does take a lot of valuable time away from the shop. I told my wife I’m about ready to retire and spend the rest of my days “playing” in the shop. She informed me that I am only 27 and probably should work a few more years. Dang her and her good sense.

Anyways I got home and put the entire saw back together, along with the new belts I had picked up last week. The saw definitely does not vibrate as much as when I started this whole mess.

I think I am going to call it good for now and if I get bored later on I’ll spend the extra cash on new pulleys and arbor.

I want to thank everyone for their help and suggestions on this. I will be continuing this blog with my side and outfeed tables as soon as I get a chance to start them.

-- Kevin, Wichita, Kansas

Thank you all again it is really wonderful having a group of knowledgeable guys I can bounce ideas off of. I’ve never met most of you but consider all whom I’ve dealt with a friend.

-- Kevin, Wichita, Kansas

Kevin thats really great to hear. I hated to see you throw more money at it if you didn’t have too.

-- If you can't find the time to do it properly, how will you find the time to fix it ?