Kmg problem.

Guindesigns

Guindesigns

Well-Known Member
I just got my kmg together about three months ago and I got problems. One is that my motor gets bog down really easy when I'm grinding on my. Another is my tracking arm is off or something cause for my small wheel attachment it is almost off the wheel by the tracking knob. Speaking of my small wheel attachment that's another problem the belt is shaken all over the place when I use my small wheel attachment. Plz help!!!
 
There are lots of possibilities......

my motor gets bog down really easy when I'm grinding
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-Is the motor wired correctly, for the current your using it on? If the motor is a 110/220V, having a single wire in the wrong place means it might still run, but can cause a severe lack of power.
-What HP is the motor? If it's only a 1hp motor......you can't expect too much out of it.
-Is it step pulleys or VFD? If you're using step pulley, remember that the higher the speed, the less power you'll produce. Also, if the motor isn't mounted correctly, and you're getting belt slip (V-belt) that can cause a severe lack of power too. If a VFD is bogging down, then it's likely that one or more of the trim pots located inside the enclose isn't adjusted correctly.

my tracking arm is off or something cause for my small wheel attachment it is almost off the wheel by the tracking knob
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-Not at all uncommon with small wheel attachments..... I've never ran a small wheel, on any machine, that wasn't significantly "off" compared to a flat platen or contact wheel on the same tracking arm. It's very rare to ever be able to change an attachment on the same tooling arm, and not have to significantly adjust tracking.

Speaking of my small wheel attachment that's another problem the belt is shaken all over the place when I use my small wheel attachment.
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-That one's a bit tougher, but my guess is it might be a speed issue. Anything smaller than a 1" wheel should run at no more then approx. 30% of the machines max speed, and then for no longer then about 10 mins..... otherwise the wheels, or the bearings, or both overheat and usually self-destruct. Generally small wheels acting like that are either about to go, or the issue is due to the abrasive belt you're running on it.
-You didn't say what type of belts you're trying to run on the small wheels, but that can also have a dramatic impact on small wheel performance.

Of course those are all just educated guesses, based on the limited information, but hopefully helpful.
 
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EdCaffreyMS said:
There are lots of possibilities......


-Is the motor wired correctly, for the current your using it on? If the motor is a 110/220V, having a single wire in the wrong place means it might still run, but can cause a severe lack of power.
-What HP is the motor? If it's only a 1hp motor......you can't expect too much out of it.
-Is it step pulleys or VFD? If you're using step pulley, remember that the higher the speed, the less power you'll produce. Also, if the motor isn't mounted correctly, and you're getting belt slip (V-belt) that can cause a severe lack of power too. If a VFD is bogging down, then it's likely that one or more of the trim pots located inside the enclose isn't adjusted correctly.


-Not at all uncommon with small wheel attachments..... I've never ran a small wheel, on any machine, that wasn't significantly "off" compared to a flat platen or contact wheel on the same tracking arm. It's very rare to ever be able to change an attachment on the same tooling arm, and not have to significantly adjust tracking.


-That one's a bit tougher, but my guess is it might be a speed issue. Anything smaller than a 1" wheel should run at no more then approx. 30% of the machines max speed, and then for no longer then about 10 mins..... otherwise the wheels, or the bearings, or both overheat and usually self-destruct. Generally small wheels acting like that are either about to go, or the issue is due to the abrasive belt you're running on it.
-You didn't say what type of belts you're trying to run on the small wheels, but that can also have a dramatic impact on small wheel performance.

Of course those are all just educated guesses, based on the limited information, but hopefully helpful.
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My motor is a 1.5hp with a pulley system. And my belts are moving on all my attachments now. I'll post a video
 
Most of these may actually be a pretty easy fix.

First, the small wheel may just out of square with your other wheels. There will be just a little bit of play between the attachment and the tool arm before you tighten the bolts down all the way. My suggestion would be to put a new belt on your main contact wheel, and track it as close to center as you can. This will be your "base line" for tracking. Now, loosen the two bolts on your SWA, and if you're looking down at it from the top, turn the whole bracket/attachment clockwise just a little bit, and tighten the bolts. Now try your tracking again. If it wants to track off the wheel worse then before, then loosen the bolts and turn it counter clockwise (anti-clockwise for our European friends), then tighten everything back up. Somewhere between these two extremes, you should find dead center. Make sense? Basically, the axle of your small wheel needs to be parallel to the axle of your drive wheel. It'll take some playing with, but you should see the changes quite easily.

As for your belt "shimmy", are you making your sanding belt as tight as possible? Push your tracking arm down as far as possible, then pull your tool arm out as far as possible (with a belt on, of course) and then tighten your tool arm. This will give max belt tension, and may take care of the shimmy. Try this on a new belt if possible. (FYI, tracking on most belt grinders tends to work better the tighter the belt is. Same with any attachment.)

If that doesn't fix the problem, you likely have a wheel alignment issue, and your crowns on your drive and tracking wheel are fighting each other. You'll have to verify that the center lines of all your wheels are in the same plane, and that the axles of each wheel are parallel, once again. This is an easy fix in theory, but practically, it can be a bit of a pain.

Now, as for the motor, are you wired for 110, or 220? Is the motor actually stalling, or is the drive belt OR abrasive belt simply slipping? Put a piece of tape or some kind of mark on your motor pulley. If it actually stops turning, then you have something wired wrong. Possibly, you're wired for 220, but plugged into 110.
If the sanding belt stops moving, but the tape is still spinning, then you have slip. Tighten the motor belt, or the sanding belt.
 
OK I just looked at the video. So I am going to go thru a few things!!

Guindesigns said:
My motor is a 1.5hp with a pulley system. And my belts are moving on all my attachments now. I'll post a video
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Guindesigns said:
One is that my motor gets bog down really easy when I'm grinding on my.
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First you say you have the 1.5 hp motor! Is it wired for 110-120V or is it wired for 210-220V?? I went with the2hp and it is wired for 210-220V so you may be slightly underpowered. Please let us know how you have the motor wired,120V or 220V??

As for the small wheel attachment I can't help you as I don't have one or have I ever used one!

OK as to the vibration, it is bad! So going to ask a few questions.
Is the whole set-up from KMG??

Have you tried another belt?? I don't really think that is the issue but have seen bad belts that can cause a vibration!!

Do you own a framing square?? When you have the belt on, tensioned and adjusted for tracking, lay the framing square with one leg on the table and use the other leg to square up to pulleys.
Do the pulleys set square at that point?? Also the square will give you a reference point to look at the sanding belt and how it relates to the line-up of the drive pulley, tracking pulley and the 10" grinding wheel! In other words they should all appear square and in-line with one another!! The tracking pulley is the only one that may be cantered slightly!

Is that 10" wheel a KMG wheel??
I have a grizzly that I had pocketed by a machine shop to accept bearings! After it was pocketed I had to re-true. Think a wheel on a vehicle has to be balanced or it will vibrate.

Have you checked each of the wheels without a belt on to see if you can notice any wobble or play??
That vibration could be a bad bearing! I

Guindesigns said:
Speaking of my small wheel attachment that's another problem the belt is shaken all over the place when I use my small wheel attachment.
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Since you are having the same problem with the small wheel attachment. That kind of tells me the vibration may be in the bearings at the drive wheel. Since the vibration is there when using the 10" wheel and their when using the small wheel attachment, it almost has to be something that is common to both set-ups!!

Last thing. Have you contacted KMG??
The short video could tell volumes if they can see it! Call their tech support and see what they have to say!!

Andrew, had posted and he has some good points as well!!
 
I have a KMG. A 1.5hp motor can be stalled using a flat platen. Not so much with a grinding wheel. You just have to grind into that. I have used a couple different small wheel holders on mine. In both cases there was a fair amount of adjustment that needed to be made to center the belt. Often the adjustment left the belt half on, half off the tracking wheel.

My KMG prefers a tight belt to track evenly. I added a leverage bar so I could really crank down on the spring for a tight belt.

As for belt wobble, sometimes flipping it to run the other direction helps. Usually just switching belts clears it up.
 
I took a look at the video, and it appears to be a belt issue. The belt is wobbling, but the contact wheel is running true..... that tells me that the belts were likely not cut square/true. (When belts are produced, their made is a huge section, then cut down to 2" or whatever width, and if the cutter is dull or mis-aligned, the edges of the belts are either cut "ragged", or out of square) I've had a number of belt orders that came in the same way over the years...... although a pain in the rear, all I've had to do is call or email Tru-Grit, tell them about the problem, return the belts, and they send me new ones. That's one of the reasons I stick with Tru-Grit, and with brand name belts......... they have a history of making things "right" for me.

There are other instances/circumstances that can come into play with any belt...... if belts hang for a long time, or are stored in a warehouse for extended periods in humid conditions, they will "curl" or otherwise get out of shape in some way or another (after you the packaging is removed).....this is another reason I don't buy from "cheaper" belt sources...... many of those, particularly the import/made in China varieties spend months on a ship getting to the U.S., then sit in a warehouse, then to whomever sells them......and by the time they get to you, they've gone through so many environmental changes, they are all "out of whack". At one time or another, I've been talked into trying most of the "low end" belts (names intentionally omitted), and have always been disappointed.

Often times it's just a matter of the user not being knowledgeable/aware of such things, and they blame it on the machine, when in truth, it rarely is.
 
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BossDog said:
I have a KMG. A 1.5hp motor can be stalled using a flat platen. Not so much with a grinding wheel. You just have to grind into that. I have used a couple different small wheel holders on mine. In both cases there was a fair amount of adjustment that needed to be made to center the belt. Often the adjustment left the belt half on, half off the tracking wheel.

My KMG prefers a tight belt to track evenly. I added a leverage bar so I could really crank down on the spring for a tight belt.

As for belt wobble, sometimes flipping it to run the other direction helps. Usually just switching belts clears it up.
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How do I check the wiring? I barely found the video to watch for the wiring I have.
 
Is your KMG a 120 vac wired motor? Double check per the above link for 120 vac 1 ph wiring. No VFD involved? As other's have said, tighten the belt up as much as possible by moving the tooling arm out as far as you can.

When you're posting another video, try moving back a bit so there is more of the grinder in the video. That one is so closeup it's really hard to tell much other than the belt is wobbling.
 
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Your drive and tracking pulleys are not lined up. The two crowns are fighting eachother. You need to slide the drive wheel either left or right on the shaft.
 
mike-E said:
Your drive and tracking pulleys are not lined up. The two crowns are fighting eachother. You need to slide the drive wheel either left or right on the shaft.
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That is what I was referring to in this post!

C Craft said:
Do you own a framing square?? When you have the belt on, tensioned and adjusted for tracking, lay the framing square with one leg on the table and use the other leg to square up to pulleys.
Do the pulleys set square at that point?? Also the square will give you a reference point to look at the sanding belt and how it relates to the line-up of the drive pulley, tracking pulley and the 10" grinding wheel! In other words they should all appear square and in-line with one another!! The tracking pulley is the only one that may be cantered slightly!
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KMG squared up.png


Don't laugh at my drawing cause this is the first time I tried Paint 3D. But imagine the blue line is a straight line. Line that straight line up square (the red square) from the line to the side of the drive pulley. Now extend that line out to the tracking pulley and out to the 10" wheel.

At each of the points with orange X you should be able to square down from the edge of the pulley and the square should land on that straight line. If they don't square down the pulley is either cantered (for some un-Godly reason) or the pulley need to be move left or right to line up with the other pulleys. All three should line up and be square from the straight line up!!!

Hope that helps to explain what I was referring to!
 
ARCustomKnives said:
Ok, then it should be wired as shown on the pdf linked above. Make sure your P and T wires aren’t interchanged.

Also, are you plugged directly into a wall outlet? If you’re running off of a long extension cord, that could cause some easier bogging as well.
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ok ill check it tonight and see if that fixes it. and yes its plugged directly into a wall oulet.
 
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