Balancing a large cast iron flat pulley

[Martin W]

Looking for suggestions on balancing a 20” diameter cast iron pulley. I trued up these two pulleys and when they are mounted to. The shaft and bearing, it will always turn to the same position.
What is the Mandrel on the fence method?
Short of drilling holes, can I epoxy some lead to the opposite side?
Also is there a way to tell how much to heavy it is on the unbalanced side?
Thanks
Martin

 

[Uglydog]

Any straight rod will work.
Try spanning the Vs on a lathe for a stand.
Consider using small washers and two sided transparent tape.

Daryl
MN

 

[Cadillac]

Look at how surface grinding wheels are balanced. Mount the pulley to a shaft then roll that shaft on either two parallels that are dead level or a bearing fixture like this
The fixture above works good and takes the leveling out it.

The heavy side will always go to the bottom. So spin and mark. then you could take magnets put opposite of your mark spin again. Where does the original mark go? Mark your low/ heavy side and add more weight opposite you mark. Keep doing so until you are able to spin your wheel at least 3-4 times without it landing at the same point on the wheel. Once you e done that you can either permanently attach the weights where their at or you drill/mill out that weight where you marked the wheel throughout this process. Tedious but works well

 

[Uglydog]

Cadillac,
Wish I had a fixture like you mention. Would be really sweet!!
Especially if it had enough swing to do large balance projects.
Maybe someday when there are deeper pockets.

Regardless, great guidance for Martin W.

Daryl
MN

 

[Cadillac]

I was lucky enough to find one at an auction for super cheap. I believe it’s an Anderson. The nice thing is it’s adjustable. I used to balance a four jaw chuck I have that was way outta balance.

 

[projectnut]

It might be a stretch to find one at a reasonable price, but there are lawnmower blade balancers that would also do the job. I have a Magna -Matic 1000 that works well for just about anything that is magnetic and has a round hole in the center. I use it to balance mower blades, surface grinding wheels, sheaves, and a host of other things. It's good for balancing down to 2 grams. The bore of the object slides over the cone. Then the magnetic base slides on the shaft until it contacts the object being balanced.

Mag1000 Magnetic Lawnmower Blade Balancer Wall Mount 750-087 | eBay

Replaces Part Numbers: 750-087, MAG-1000, Mag1000. Wall mountable. Cast Aluminum Wall Mounting Base - High Gloss Finish. Steel En Fits Cased & Polarized Permanent Magnet. Ability to be used with the MAG-10200 Service Center Stand.

www.ebay.com

New they're expensive at between $179.00 and $285 depending on the model. However, they do occasionally show up on eBay for considerably less. There are a number of used ones and Chinese knockoffs currently on eBay.

 

[Uglydog]

It might be a stretch to find one at a reasonable price, but there are lawnmower blade balancers that would also do the job. I have a Magna -Matic 1000....

Projectnut,
Wow. Certainly a move up from the stepped cones. How does it balance? Rides on a ball, a point or other?

Daryl
MN

 

[Cadillac]

The magna matic has a centering point which centers your blade. The center has a bearing with a magnet on its face that mounts the blade to the balancer. They work great for the purpose. The problem I’d see using would be if the magnet ban suspend the 20” cast pulley. Idk

 

[RJSakowski]

I use the shaft riding on leveled rails for balancing outboard props. Sensitivity can be down to a fraction of an gram so it should be a piece of cake for a 20" diameter pulley. My mill bed is set up to be level with a machinists level and I use 1-2-3 blocks for the bearing surface.

Bear in mind when adding balancing weights or drilling holes for balancing that the effect varies with distance from the center so if you are using trial weights to balance, they should be at approximately the same distance from the center as the final adjustment. If not you will have to compensate for the difference in distance. The safest approach is to put your trial weights as far to the outside as possible. For actual or trial balancing, tire shops use adhesive backed lead weights which make for easy adjustments. In my mind, drilling j holes is superior to attaching extra weight as it is permanent.

 

[toprecyler]

Here is what the instructions said to balance tires on an old Snap-on manual balancer.

Place weights 120 degrees apart opposite heavy end. If possible split those weights between both sides of the rim.

Using this info, may give you other thoughts on how to best balance your pulley.




Sent from my iPhone using Tapatalk