What causes idler pulley wear?

[Nathan the Machinist]

I've seen that before and it wasn't bearings or tension, I think something is out of square. When the aluminum wheels are wearing funny it's because the belt is shifting as it goes around them.

In an ideal world the tracking wheel doesn't do anything. The more out of whack things get the more work it does.

Try running your grinder forward and reverse with and without the tracking wheel, should all be about the same. If it's not you might need to adjust something. I've had to turn the tracking wheel block some to get it running straight in a level neutral position. The drive wheel axle can be out of wacky, the platen or idler wheels can be wonky, or things can simply not be aligned so it requires an adjustment to get the belt centered. If that's the case don't track the belt over, move the platen.

This is my grinder

When you get everything straight, aligned and square it will track like that. That's the original tracking wheel, it's ten years old, it has thousands of hours on it and no real wear.

 

[skillgannon]

I've seen that before and it wasn't bearings or tension, I think something is out of square. When the aluminum wheels are wearing funny it's because the belt is shifting as it goes around them.

In an ideal world the tracking wheel doesn't do anything. The more out of whack things get the more work it does.

Try running your grinder forward and reverse with and without the tracking wheel, should all be about the same. If it's not you might need to adjust something. I've had to turn the tracking wheel block some to get it running straight in a level neutral position. The drive wheel axle can be out of wacky, the platen or idler wheels can be wonky, or things can simply not be aligned so it requires an adjustment to get the belt centered. If that's the case don't track the belt over, move the platen.

This is my grinder

When you get everything straight, aligned and square it will track like that. That's the original tracking wheel, it's ten years old, it has thousands of hours on it and no real wear.

I'm not sure if I have my terminology wrong. I am talking about the wheel that I adjust my tracking with. Is a idler pulley different?
Your explanation sounds right. My platen and 8" wheel track differently. Would this indacate that is the problem? How would I adjust this?

 

[Drew Riley]

I'm not sure if I have my terminology wrong. I am talking about the wheel that I adjust my tracking with. Is a idler pulley different?
Your explanation sounds right. My platen and 8" wheel track differently. Would this indacate that is the problem? How would I adjust this?

Wait... is this your tracking wheel? Technically, yes, it is an idler, though typically the platen wheels are more commonly referred to as idlers, and the tracking wheel as... well, a tracking wheel.

As for how to check if there's a spacer in between the bearings, Brett from Esteem should be able to tell you. If not, you can just just take your wheel off and look through the inner bearing race. You should be able to see if there's a spacer or not. It'll be roughly the same ID as the bearings. If you can see a larger cavity bored in between the bearings, then you probably don't have a spacer. I know that's not a great explanation, but at any rate, your tracking will should keep spinning if you roll it by hand, like a skate board wheel, as Stacy said. If it immediately stops, then something is binding.

I recommend this wheel for a replacement:
https://www.ebay.com/itm/Belt-Grind...024213?hash=item35e2202555:g:LV4AAOxyVLNS1y0P

It comes with a spacer, and the bearings have a larger than average inner race, so you can use machine bushings OR a regular flat washer when you mount them to your machine.

 

[skillgannon]

The bearings are fine both times. Its gotta be something like Nathan said but I can't figure it out

 

[Stacy E. Apelt - Bladesmith]

I did not realize you were talking about the tracking wheel.
Stand a couple feet away from the grinder with the belt off and look at the tracking wheel so it is just above the platen wheel ( or contact wheel) in you line of sight. Does it look angled any at all????? If so, that is the issue.

 

[WhitleyStu]

I did not realize you were talking about the tracking wheel.
Stand a couple feet away from the grinder with the belt off and look at the tracking wheel so it is just above the platen wheel (or contact wheel) in you line of sight. Does it look angled any at all????? If so, that is the issue.

With tracking being adjusted with this wheel how can it be in line with platen or contact wheel. My 3M Cubitron and Trizact track slightly different so adjusting the camber of the tracking wheel is needed to keep each belt centered on platen.

Edit: I just looked at Esteem grinders and see they use a toe in/toe out tracking adjustment as opposed to my camber tracking adjustment. It very well could be the belt not moving at 90° to the tracking wheel's axis as stated in post #8.