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I stuffed up the conveyor belt on my drum sander recently, and have a new replacement belt. Problem is that following the instructions in the manual has not produced any positive results.

The instructions are rather vague on how much tension that you need on the belt, but state that it needs to be right, or you'll never get the belt to track correctly. Then they say that once it's tensioned correctly, you increase tension on the side that the belt need to move from, and decrease tension on the side you want it to move towards.

I've been working on this for 3 afternoons now, and can not get the belt to track. I've reversed the belt as well, but in all cases the belt moves to the outboard side. It seems that no amount of adjustment to the two adjusters will get the belt to want to track to the inboard side of the sander.

Any tips or suggestions on how to go about this before I spit the dummy and drive over the sander with the ute?

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Allen R. McFarlen
Barron River Guitars & Ukuleles
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Cairns, Australia

Are you using the plastic guides/magnets that go under the conveyor belt? They really help keeping the belt on track.
Tension the conveyor belt enough so there is no kink or crease in the belt. When it goes one way (on the left, say) crank the left tensioner bolt 1/4 turn (counterclockwise). And so on. It can take over a week for the whole mechanism to reach "equilibrium", meanwhile keep an eye on the belt and the allen key close by.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

Allen my friend here is a very good thread from about a week or so ago where this is discussed. Check out Colin's comments - I plan on trying his method since I never got my 10-20 to track correctly.

http://luthiersforum.com/forum/viewtopic.php?f=10101&t=19537&p=274259#p274259

Hesh, thanks for that link to Colin's info, I found that plastic block up under the motor just sitting there, had no idea what
it was for. WIll now use it as a rest for the open end when not in use.
The best help I found for tensioning the conveyer belt was to measure the length on both sides of the table first and get it exact with the adjustements for that purpose then slide the belt on and adjust it. I also switched the belt around so it moved in the opposite way and that seemed to help as well. I just let my hands rest on the belt with no force and if it keeps going, I'm usually ok.

Best
Bruce

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Bruce Herrmann
"What lies behind us and what lies before us are tiny matters compared to what lies within us."

Hesh, I had read that thread and tried to get this to work. I'm using the ceramic guides and it ends up buckling the belt on the left side due to the belt wanting to track to that side. I suspect that this is what stuffed up the original belt, and I hadn't noticed it doing this in the first place.

I've use my verier calipers to make the adjusting roller the same distance on both sides. and still this hasn't seemed to work. Back to square one it seems.

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Allen R. McFarlen
Barron River Guitars & Ukuleles
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Cairns, Australia

Darn it, I just posted a little while ago on some other thread to make sure you write down what works (for any operation) because you never know what you'll forget....I had the same problem, fixed it and now have forgotten.

If I recall though I was using way too much tension. I cranked it way down and then got it even. I loosened instead of tightened to get it to track right.

The only thing is that if you're set on really thin the drum will hit the conveyer. Using a backer board eliminates this.

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

Still not been able to get it even. I have the tension way down. In fact when I thought that I might be able to live with it where it was, I tried to send a board through it and the belt just slipped and stalled, so I had to start increasing tension by 1/8 turn each side until the belt wouldn't stall.

Belt is back on the edge of the outboard side of the rollers, because that is where the tracker stops it. On the under side of the machine the belt has a pronounce buckle at the tracker, I'm at a loss as to what to try next, or just to have to live with it as is.

Has anyone tried to wrap tape on the adjusting roller to give a bit of crown in the center, to aid in tracking?

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Allen R. McFarlen
Barron River Guitars & Ukuleles
Facebook
Cairns, Australia

Allen my friend after reading this thread last night I started messing with my 10-20. You should have seen the look on my face when I found out that the white guides are magnetic..... I thought that I broke my machine when one came off in my hand.

I tried everything mentioned and a few other things too and mine still always tracks to the inboard side, opposite of yours.

If it helps any I have been running mine for a couple of years with the belt tracking all the way to the inboard side and it does not seem to cause any problems. In fact the slight ridge that these machines can produce with double pass sanding does not happen on my machine and I think it is because the belt, not being under the outboard edge of the drum, does not cut the ridge. I keep a spare belt here at Heshtone Global Headquarters for when this one wears out but so far I see no indications of wear.

The net, net for me is that in my case, inboard tracking, it is more an annoyance than anything else.

When you like things to be either straight, or curved to your specifications, having a belt not sit where you want it is one of God's tests for me I think.

I haven't had the opportunity to try wrapping the masking tape on the idler roller to make the tapered cylinder. But as it stands right now, If the belt is going to work in this fashion, then I might just have to give in and live with it. But you know I'm going to loose sleep over this.

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Allen R. McFarlen
Barron River Guitars & Ukuleles
Facebook
Cairns, Australia

If ran over tight for an extended time you will warp the carrier belt ( one end slightly longer than the other. once this happens it is tuff to get the belt to run straight. The proper adjustment is to bring the rollers into contact to a new track belt and tension up a tad. run at slow speed to see which way it is running out and tension towards the run out and slack off away from it a bit at a time. Small adjustments mean a lot here. The idea is to get the rollers dead parallel to each other and the belt. if the belt is stretched on one side more than the other this is tuff.

I got mine adjusted when I first got it and have not had to change it in 2 years now

I've been trying to adjust this thing all day, and at 36 C it's getting a bit hot under my collar.

Here's what I've tried now. The belt tracks to the left (outboard side) in all cases. It has not been possible to get the belt to want to move to the right (inboard side).

-Flipped belt both ways, and no effect whatsoever.
-Wrapped 2 turns of masking tape on adjustable roller in several spaces to simulate multi-tapered roller.
-Wrapped tape in middle of adjustable roller to make tapered roller
-Run belt with low tension. Hand can stall belt. Gradually tighten 1/8 turn each side until belt will not stall.
-Tried without trackers. The belt will spit right off the rollers.
-Measured and adjusted adjustable roller so that it's within .01 mm of each other from platen on each side.
-Adjusted motor end of feed roller so that it is the same distance below platen on each end. This had a slight effect, so I tried it in the extremes of each way to see if I could get a movement to the inboard side. No luck
-Adjusted end bracket to get platen level.

I've done all this several times over. Searched the internet for solutions, and it seems that to get these things to track correctly is either the best kept secret, or the luck of the draw. It does seem that there are an inordinate amount of tracking complaints with this unit. Many people saying that they go through several belts a year because the edge gets chewed up by the trackers. This is what happened to mine.

If I could ever get the belt to move to the inboard side, then at least I would know that I've made some sort of progress.

Does anyone know if by feeding stock through, this helps to keep a belt tracking correctly? For example, have you noticed that the pressure and tension that is placed on the feed belt by sanding helps to keep things lined up?

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Allen R. McFarlen
Barron River Guitars & Ukuleles
Facebook
Cairns, Australia

Allen,

Have you measured the new belt to check it was jointed correctly?

One thing I learnt playing around with mechanics is never to assume that just because a part is new it is not at fault, I guess the fact that you have flipped the belt can rule this out but it may be worth a look. One other thing to try is to get hold of a 100 grit sandpaper belt, at least your adjustments will be more effective as there is less stretch in the thin abrasive belt than in the rubber job.

Cheers

Kim

Allen my friend on mine the stock will not keep the belt centered.

I gave up too but like I said I have run this sander for probably 10 guitars now and the original belt shows no sign of wear and the sander works fine too.

Sorry I can't be of any help here - I was never able to get mine to track correctly either but it seems to work great anyway and I keep an extra OEM belt in the shop just in case I need one someday.