Belt Grinder Wobble

[javajaws]

Didn't want to hijack that other guy's thread, so I opened a new one:

So what amount of belt wobble is typical/acceptable? I'm completing my new grinder and have just the slightest amount of wobble - less than 1mm for sure but not 100% wobble free.

Also, I assume the "bump" in the sound is from the belt joint?

Here's a couple videos, one at 30% and another at 70% RPM (I have the tracking adjusted off-center slightly so you can see the movement better against the platen backing plate):

[video=youtube;5CqYQTJD8Tw]https://www.youtube.com/watch?v=5CqYQTJD8Tw[/video]

[video=youtube;wBOiRyGXC1g]https://www.youtube.com/watch?v=wBOiRyGXC1g[/video]

 

[drysideshooter]

I am guessing the small amount of movement you are getting is from wheels not being quite perfectly aligned. What I did, was once I had my wheels perfectly aligned with great tracking I measured the distance from a set point by each wheel to the outer edge of each wheel. On my grinder, it's only the drive wheel that has ever moved. Even with the set screw set tight it will move a small amount over time. When I notice it I loosen the set screw and move it back per the measurement.

My grinder is set up so that when I put my flat platen in the tool arm it is properly aligned when it's all the way against the tool arm. I have noticed others where there is a gap. If I had one where there was a gap I think I would mark where it's supposed to be for proper alignment with some Dykem, a sharpie, scribe line or something.

 

[mike-E]

that grinder is running awesome. most belts will have side to side movement and some will get straighter with a little run-in time. you should post some pics.