6x48 belt sander - tracking.

[Cliff Rohrabacher]

I'm having issues getting a belt to track straight.

It goes off in different directions at the same adjustment position.



I am thinking that some belt sander drums are conducive to true tracking on a belt sander and other are awful. Or maybe it’s the belts that go bad. Maybe after being used a certain way some belts just won’t track any more.

My 26+ year old Makita track sander tracks like champ and I’ve beat the daylights out of it.

I have a 6x48” belt sander I picked up cheap. I had a terrible belt tracking adjustment system so I replaced it with 5/16-18 threads that lock and can drive either end of the driven roller. This allows me to apply a very fine smooth adjustment. I had to machine up some aluminum components to get this accomplished and it’s done and it works and I can lock everything in place too. It’s got new bearings on the rollers so it’s not the bearings.

However I have tracking issues. It’s a beast to get it to track straight and sometimes after I’ve had it running OK for a week or three it just picks a moment to send the belt off track. And off the sanding belt goes. Usually it’s into the cast iron housing.

So I adjust it. I get it running just so and off the belt goes again. Then I re position the belt without altering the adjustment and start it up and dam if the belt doesn’t go off – but in the other direction.

I worked for decades as a machinist using belt sanders in all the shops where I’ve worked and never saw the likes of this fickle conduct.

What do you think? Is it the belt or the rollers? Or are there dwarves.

[Matt Meiser]

I've had problems with mine tracking right with cheap belts. Better ones seem fine. I'm not clear if you've tried a new belt?

[Cliff Rohrabacher]

I've had problems with mine tracking right with cheap belts. Better ones seem fine. I'm not clear if you've tried a new belt?

While I hate to toss a belt that's still got lots of life in it I may have to swap it out.

[Steve Clardy]

My old sears that I used to have had the same problem.
Wore out and replaced the roller bearings several times.
The last time the roller I.D. wouldn't hold new bearings anymore.
I replaced the roller and never had another tracking problem.

[Cliff Rohrabacher]

My old sears that I used to have had the same problem.
Wore out and replaced the roller bearings several times.
The last time the roller I.D. wouldn't hold new bearings anymore.
I replaced the roller and never had another tracking problem.

Hmmm, so the bearings were too loose in their bores.
And your issues were similar the couldn't make up it's mind which direction it wanted to shrug the sand belt off from - and that's without you having made any adjustment~!?

Thanks I'll look into this.

Let me guess. Getting the belt to stay on usually meant that you had to have some percentage of the belt tracking permanently off the cast iron surface.
Izzatso?

[Steve Clardy]

Yep. Belt had a mind of it own.

I think between the bearing holes being too loose, and the roller not having any arch? to center the belt, that there was no way to keep it aligned.

[Ed Gerken]

I have a worn-out 6x48 HF import cheapie, given to me by the place where I worked when they upgraded. It was mostly used to sand the edges of soft rock plates with fossils in them.

It took a lot of tweaking at first, I suppose the work broke the belts in quickly. Spring tension was abysmal even with the retracting bolts fully loosened, so I added several thick washers, this helped a lot.

Before they got rid of it, er, I mean, gifted it to me, they bought a whole bunch of Klingspor belts for it. With these, it's worked great for everything I throw at it. I'm just about on my last belt after 7 years and I bet my local hardware has about zero of 'em in stock!

-Ed

[Cliff Rohrabacher]

Yep. Belt had a mind of it own.

I think between the bearing holes being too loose, and the roller not having any arch? to center the belt, that there was no way to keep it aligned.

I have an arched (Barrel shaped) top Idler belt pulley.

Did you have to replace the shafts also?
Which pulley was your bad one the drive or the idler? Both?
They are about $35.00 each and the shafts are around $20.00 each.

I suppose for the $40.00 I paid for the thing (the bearings are new) that a hunnert buks to get 'er dun shouldn't be too much to pay.

The motor I got with the thing was a laugh. I can't for the life of me imagine how an 3/4-HP motor was expected to drive that thing. I tossed that mouse of a motor in the junk pile and put a recycled 5-HP electric lawn-mower motor on it. It's noisy but it can almost keep up with what I demand of it.

[Steve Clardy]

It was the driven roller I replaced.
Used the same shaft.
Yea I put a 2hp motor on mine.
That wimpy 1/2hp didn't cut it.
I could stall the motor by pressing down on the belt gently

[Cliff Rohrabacher]

It was the driven roller I replaced.

Thanks I'll pull that one off first.

Used the same shaft.

That's encouraging.

Yea I put a 2hp motor on mine.
That wimpy 1/2hp didn't cut it.
I could stall the motor by pressing down on the belt gently

There are things that some manufacturers do that absolutely mystify me. Building a piece of equipment and selling it with a motor that can barely make the machine go round under no load is among them

I have a pool pump that burnt out solely because the drooling morons at Hayward failed to spec a continuous duty pump guaranteeing that when a $2.00 seal fails and the pump can't self prime that the motor will cook off 'cause the only way their crappy motor can work is if the pool water is cooling it constantly.

It's not the engineers it's marketing. There was a time when Engineers built things. That time is gone. Now Marketing hands the engineers a list of horribly wrong and stupid things to do and they have to do it.
What a world what a world.
Please Dorthy, just throw that bucket of water on me.

[Cliff Rohrabacher]

Spring tension was abysmal even with the retracting bolts fully loosened, so I added several thick washers, this helped a lot.

Spring tension? Springs?
Where were these springs?

[Ed Gerken]

Hi Cliff,

Said sander is at least 20 years old and cost about a hundred when new. It has short, beefy springs which push from a piece of angle against the idler drum's shaft. Swivel bolts pin to the shaft and go through the springs and angles where they're fastened and adjusted for length by large, thick nuts. Tightening the nuts on the other side of the angle compresses the springs and withdraws the drum, which slackens the belt for changing it.

It seemed like it was designed more for a shorter belt. It was so loose at "full" tension the belt wouldn't even lay flat! My quick answer was to insert several washers that gave the springs more reach, base tension or however you put it, which allowed the drum to extend far enough to work properly. Longer springs would be better, but this has worked since.

While thinking about why this tensioning method seems unusual to you, I realized it's probably because this machine is actually a 3" by 36" (or whatever) sander! Whoops! I've never bought a belt for it, still, I don't know why I was drawing from memory that it's a 6x48!

Hmm, 3x36=6x48. No wonder all those boards I just cut don't fit.

But the Klingspor belts are still great, LOL!

-Ed