10" Wheel Belt Wobble

colu41

colu41

Joined
Dec 24, 2014
Messages
1,598
So I got my 10" contact wheel today. Super excited about it btw. Anyways, go it on. Measured out all the spacing, between the grinder, and compared to the tension wheel. Everything LOOKS perfect to me, but it still has quite a bit of belt wobble.

I know from the start that my drive wheel was set a little too far to the left, so the belt rides on the right side of the drive wheel. I ended up adding tape to the right side to even it out, and with my flat platen, the belt rides as true as you can get.

Any suggestions? I tried more spacers, less spacers. Shimming sides I thought may be too low, or too high. I cant figure this out. Any tips would be greatly appreciated.

Heres a quick video.

[video=youtube;10F5-IFKN3A]https://www.youtube.com/watch?v=10F5-IFKN3A[/video]
 
First thing is to remove that tape. That is not how you get a grinder to track right.
 
i think your belt needs more tension. when you have the belt tensioned correctly you should be able to pluck it and hear a twang not a dull thud. also if the ''crown'' of your tape wobbles it could make the belt wobble.
 
Lieblad said:
Tape ? thats new to me.
Is tape supposed to build up crown on a wheel ?
Click to expand...

Its suppose to, supposedly. I was suggested by multiple people here.

Stacy, if I remove the tape from the drive wheel, will the fact that its a good 1/4" to 1/2" too far left be fine? Eventually I want to make it right and fix it, but it seems with the mount thats on that motor, once you drill theres no adjusting other than forwards and backwards. Maybe I should file out the mount so it can move side to side.
 
Soooo. I tightened the belt tension just slightly. Decided to throw on a different belt, and theres little to no wobble now? I thought well maybe the first belt I tried was just cut bad. I put it back on, and that ran true also.

So the belt tension was the trick. I'm guessing also that it may have completely mashed down the tape I put on the drive wheel so now it may be conformed to the belt? Not sure, but anyways I'm happy.

[video=youtube;f96NXtGFGCs]https://www.youtube.com/watch?v=f96NXtGFGCs[/video]
 
colu41 said:
Soooo. I tightened the belt tension just slightly. Decided to throw on a different belt, and theres little to no wobble now? I thought well maybe the first belt I tried was just cut bad. I put it back on, and that ran true also.

So the belt tension was the trick. I'm guessing also that it may have completely mashed down the tape I put on the drive wheel so now it may be conformed to the belt? Not sure, but anyways I'm happy.
Click to expand...

Yes, we mentioned it in this thread
http://www.bladeforums.com/forums/showthread.php/1329858-2-x-72-Belt-movement

If you've never run a 2x72" before it takes WAY more belt tension than you think it should.
 
Crowning with masking tape on the idler wheel and good spring tension can really help if the belt is sliding over a lot when slack grinding. by the way I have found lining uo the front wheel with the drive wheel not the idler is the way to go.
Frank
 
12345678910 said:
Yes, we mentioned it in this thread
http://www.bladeforums.com/forums/showthread.php/1329858-2-x-72-Belt-movement

If you've never run a 2x72" before it takes WAY more belt tension than you think it should.
Click to expand...

Duly noted. I just didn't realize how much more tension it really needed. So I actually mocked up a small bar on my tension arm so I actually have leverage instead of trying to practically stand on the thing while pulling out my tool arm :grumpy:

Either way. Thanks all. Shes working great now. Think I'm going to practice some hollow grinds tonight....:D
 
On my GIB I use a 60lbs spring
 
A drive wheel has only one task on a grinder.....to drive the belt forward. It should be flat and aligned in all axes with the contact wheel. Often it is wider than the contact wheel. 3" wide is a good size. This allows the belt to be moved side to side in tracking alignment but maintain full belt contact and power from the drive wheel.

The tracking wheel is crowned to make the belt track straight. It should be under sufficient pressure to allow proper tracking and belt tension. Tape will help here sometimes, but is a temporary fix. The wheel should be properly crowned to provide the tracking, but also should not need excess crowning to maintain it. Too much crown will shorten the belt life.
 
Everything Stacy said is true, unless it hinges on the original design of the grinder maker. There are some designs that utilize crowned drive wheels.

Before you do anything, you should be squaring up your machine. I know you don't want to hear this, but if your drive wheel is out of alignment with the rest of your setup, it will NEVER work the way you want, and you'll be fighting the machine forever. MAKE IT RIGHT.

After you've got the wheels aligned, FIX YOUR TENSIONER. Without more leverage, you'll never get shit running right. The idea is to be able to compress the spring entirely, put a belt on, pull the tool arm out until the belt is tight, tighten the locking screw, then release the spring tensioner. That gives you the force of the spring. You're just barely getting that spring to compress, and that's not enough. Just like the Count pointed out, your previous thread shows this.

I'm harping on you.

There's a reason.

I dealt with this for way too long. It lengthened the learning curve by a ton, and limited my ability to grind accurately because I was always fighting the machine.

FIX THE PROBLEM!

Hate me now for being a bully about this, but thank me after you spend the time it takes fixing it and realize that everything is easier and works better.:)
 
Thanks Matthew. I originally wrote "most grinders" the first sentence, but made it more stern since I knew he had a three wheel grinder.

I find that 99% of grinder problems can be fixed with the two simple things you suggested - Align all wheels perfectly, and put sufficient tension on the belt. If it is square and tight, even a belt with a bad splice will track pretty good.
 
I knew you knew. ;)

My Wilton's was flat, but the KMG is crowned. I think Bader's are, too, but I can't remember. The rest of the newer crop of grinders... Dunno. doesn't matter. EVERYTHING could be crowned, and it wouldn't make any difference if the wheels are fighting one another because they aren't aligned. That's a HUGE advantage to direct drive. The KMG I have now absolutely sucked to align. Took two days. Nothing indexes properly. No good, legitimate baseline to start from. After modifying the snot out of it, it's much better, but I still think I should have made it direct drive. Guess it's not too late, but I want make knives, not grinders!
 
Matthew Gregory said:
I knew you knew. ;)

My Wilton's was flat, but the KMG is crowned. I think Bader's are, too, but I can't remember. The rest of the newer crop of grinders... Dunno. doesn't matter. EVERYTHING could be crowned, and it wouldn't make any difference if the wheels are fighting one another because they aren't aligned. That's a HUGE advantage to direct drive. The KMG I have now absolutely sucked to align. Took two days. Nothing indexes properly. No good, legitimate baseline to start from. After modifying the snot out of it, it's much better, but I still think I should have made it direct drive. Guess it's not too late, but I want make knives, not grinders!
Click to expand...


Thanks Matthew & Stacy. As of now it is temporarily fixed. I will be remounting the motor and pulling the tape off the drive wheel, just to assure everything is straight. I will also be building an arm for a tension bar so its easier. That will have to hold off a bit though as I'm currently building my shop into its own room in my garage. Currently not insulated, ( I live in Michigan) :eek: So, I got a wall built, and insulated, just need to finish the ceiling and setup my heater. Then back to work
 
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