Wobbling belt..?

[StevePryor]

On my older B-II the belt wobbles wildly from side to side no matter what wheel or platen I run on it. I've tried building more of a crown on the drive, and on the idler/tension wheel seperately but it seems to make no difference. The wheels all seem solid and have no noticable play in the bushing/bearings, whick leaves me at a loss as to what could be causing this. Anyone...? TIA.

[Bob Warner]

Are you sure that nothing is loose? I mean it could appear to be tight but not quite. If the shapt wobbles, the wheel will wobble. If your wheel is allowed to move from one side to the other (Slide across the shaft a little) it will wobble.

Have you used all of these componenets before or have you added an unbalanced item into the mix?

[george tichbour]

I have had a similar problem in the past. The solution was simple, the peak of the crown on the idler wheel was not in line with the center line of the contact wheel. (I run a two wheel setup, a driven contact wheel and an unpowered idler wheel) .

[Geno]

This may or may not apply here, but old belts run wobbly.
When I store them for any amount of time, they don't seem to run true anymore. New belts generally don't do this. The older the belt is, the more wobbly it becomes.

Are you using those discount belts from Industial abrasives by any chance? Every one of those was bad, I quit buying from them for that very reason.

Tru Grit makes all mine and puts them on a heavy "X" weight paper for me. I have not had a problem since.

[John Frankl]

I am not disagreeing with anyone here, but I tend to think it might be the Bader machine itself. They are good machines overall, but tracking and wabbling do seem to be recurring problems. I have had the same problems on all BM-2's I have used, and some others report similar bad luck with BM-3's (after a bit of use).

John

[Rob Frink]

Steve,

To help determine if it is the belt or the machine....take note at the frequency of the wobble.....the number of times the belt moves everytime it goes around.

If it wobbles side to side...say 4X for every belt rev...then you can look at the wheels/roller since they turn about 4x per belt rotation.


However, if it just moves once per rev....and it is the same part of the belt that moves..(mark it with a marker) then you have determined that it is a wobbly belt. Some belts just wobble...even premium and new. Higher quality belts are better though. Also, older belts that have been sitting around picking up moisture (curl) may wobble...or belts left on the machine with tension. For me , wobbly belts tend to straighten themselves out after running them for a while.....I think they warm up and stabilize...


Other than that...it sounds like you've given the machine a look over for obvious stuff...like loose wheels, bolts, ..knobs.etc.

Good luck with it...and please post us if you nail the problem.

Sincerely,
Rob

[StevePryor]

After extensive belt testing today the problem has been solved. I did extensive testing with the 20 belts in use in the shop at this time, of varying age, weights, and brands. Five out of the 20 had some side to side while running, with no regard to age weight or brand. It just so happened that these 5 were the most frequently used ones when this problem was noticed...go figure! In summary;the fault does not seem to be the grinder being a Bader, or any particular age, weight/brand of belt. I guess for whatever reason...some belts wobble, but not sure in like the ratio...
Problem has been diagnosed...i think.

Thanks for the replies guys.


Steve (Back to grinding.)