Sanding Belt Direction?

Is this important? I have a vertical machine in which I tend to wear out th e rightmost 15 percent of the belt and change it having never really used t
he leftmost 20 percent. I suppose I should try reversing the belt first bef ore posting the question, but I'm lazy and bored. Does anyone do this?
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On 5/27/2014 6:03 AM, robobass wrote:

You might tear a hole in the space-time continuum!
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I think I already have. I just posted something else to another forum a few minutes ago, and saw this:
Investigators have determined that an incidental rift in the time-space con tinuum likely created a critical warp causing the entire universe to invert - aligning the runway to the top of the plane. The pilot was unable to reac t in time causing the aircraft to come to rest on its roof. Climate scienti sts claim that this anomaly is a result of excess carbon gases which are a hallmark of climate chaos. Next to melting polar ice caps and feces throwin g monkeys, this is the most common occurrence related to the needless delay in enacting global carbon taxes and issuing carbon credits. Citizens are u rged to demand their legislators pass this world and polar bear saving tax at once. Remember, not only does the future of our children depend on it- b ut also the future of our children's children's children... and their child ren as well.
Zeitgeist. No?
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On 5/27/2014 5:47 AM, Tom Gardner wrote:

It does make a mess, doesn't it.
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On 5/27/2014 7:30 AM, Richard wrote:

Nothing a little duck tape can't fix.
David
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On 5/27/2014 12:43 PM, David R. Birch wrote:

I sent a note to "Duck Tape" who's factory is a couple of miles away, to ceate a new super tape to compete with the likes of "Gorilla Tape". My suggestion is to name it: "BOOGER TAPE".
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Yes, direction is important. The belt necessarily overlaps at the seam, and you need to have it moving in the direction that *won't* tend to peel the seam open from friction. Running the belt in the wrong direction risks a sudden delamination of the seam.
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Am Dienstag, 27. Mai 2014 13:17:38 UTC+2 schrieb Doug Miller:

nd you need to have it

tion. Running the belt in

I understand the argument, but when I look at the seam I don't see how it w ould make a difference. I always thought that the bigger issue was how the belt gets broken in, and that a used belt would be to biased as to shape to stay on the rollers if reversed. I'm about to change a worn belt. Will try it in reverse and see what happens.
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robobass wrote:

It depends on the type of seam at the joint . Older belts have a lap joint , many of the new ones have a fiber-reinforced butt joint , and those can usually be ran either direction . If your belts have what looks like a really wide piece of stuff that resembles filament tape on the back side of the joint , you should be able to run it either direction . Might need a minor tracking adjustment .
--
Snag



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On 5/27/2014 7:25 AM, robobass wrote:

...

_MOST_ do have an overlapping seam; a few manufacturers use a butted seam (Klingspor is one that comes to mind), but even they iirc have a suggested direction of travel stamped on them.
Undoubtedly robo's belts will have a direction mark as well; how well/long it'll work the other way will have to do with just how good of shape the seam actually is and whether it is a lapped or butted one. But, I'd expect it to be shorter than it would be otherwise.
Then again, if it's replace it otherwise, whatever extra gets from it is gravy...
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"Then again, if it's replace it otherwise, whatever extra gets from it is gravy... "
Yeah, I don't actually pay a lot for my belts anyway. They are an odd size which fits a popular hobby machine in Germany, but are plentiful on Ebay. W ith a closer look I see that it is indeed an overlapped seam, so this may n ot work at all. Nothing to lose by trying it though.
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Well, I just tried it. Result? Yes and no. It's harder to adjust on the rollers, but does get into line with a bit of fussing. I can sand in free air (above the platten) with no trouble. But trying to sand against the platten is a no go.
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On Tue, 27 May 2014 07:02:42 -0700 (PDT), robobass
It has probably stretched a skosh. Once it runs for a few minutes, it may settle down as the other side stretches to equalize.

Final result: No. Those particular belts aren't built for it.
--
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necessary that he should not only be capable
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I understand the argument, but when I look at the seam I don't see how it would make a difference. I always thought that the bigger issue was how the belt gets broken in, and that a used belt would be to biased as to shape to stay on the rollers if reversed. I'm about to change a worn belt. Will try it in reverse and see what happens.
It depends on the belt. Some belts have a scarfed and lapped seam. It is important to drive these in a direction that won't catch the flap on the workpiece Other belts have a butted and taped seam. On these direction is not important.
Paul K. Dickman
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On Tue, 27 May 2014 07:41:47 -0500, "Paul K. Dickman"

Critical in early steel belted radial tires, but I believe they overcame the problem. I still don't like to cross-switch, though. When a steel-belted tire comes apart, it can take half the vehicle off as it swipes the side of the car. That's an expensive test. With most motor belts, very little (if any) damage results when it lets go. Ditto sanding belts. They usually just break and stop exactly where they broke. (I'm sure we'll hear stories to the contrary any time now, though. ;)

Exactly. Some belts are built to be used in either direction, others aren't.
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Critical in early steel belted radial tires, but I believe they overcame the problem. I still don't like to cross-switch, though. When a steel-belted tire comes apart, it can take half the vehicle off as it swipes the side of the car. That's an expensive test. With most motor belts, very little (if any) damage results when it lets go. Ditto sanding belts. They usually just break and stop exactly where they broke. (I'm sure we'll hear stories to the contrary any time now, though. ;)
Well, going off topic, I'd like to hear a real story about a car radial tak ing off half of a car. At least in the last 40 years. I reverse rotation, a nd run used tires all the time. I'm 51 years old and regularly drive on the German Autobahn. I have never seen a car radial tread break loose and flap . It gets my blood up all of these urban legends propagated by fraudster ti re sellers. My father-in-law will no longer rotate his tires front-to-back. His garage told him that the rims mate to the hubs when first installed, a nd won't be properly aligned if placed on a different hub. I asked him if t hey marked the bolt holes to make sure that the rims would go back onto the hub the way they came off. He didn't know, of course, and I'm sure they di dn't do it.
Sorry to go off on a rant, but, if we are to continue as a species, people need to learn to separate "that which is empirically and observably true" f rom "that which someone once said"
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Yeahbut... (my life is dedicated to the "yeah, but")...
Did that happen because you reversed the rotation of the tire, or simply because the tire and belt decided to part company?
IMWTK.
LLoyd
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NO, Gunner! <G> I meant, did you ROTATE THE TIRES so they were rotating contrary to their originally installed rotation.
THAT is what the tire dealers tell us will cause a belt separation.
Didja notice they don't "X" radials at most shops, but only change them from front to back?
<BACK UP on a blown tire? HEE! HEE!>
LLoyd
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"Lloyd E. Sponenburgh" <lloydspinsidemindspring.com> wrote in message

http://www.tiresafety.com/maint/maint_content.asp "Straight Rotation was developed in the early years of radial tires. This rotation method simply replaces the front to rear and rear to front and is used for directional tread patterns."
The article suggests, but doesn't declare, that the problem with early radials taking a directional 'set' has been solved.
jsw
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I agree, and some vendors do, too. But a lot of tire shops are still stuck in the '70s in that respect.
Lloyd
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