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Zlatko Kursar
01-29-2011, 3:31 AM
Why is this happening. This is my second belt. I've checked all the passages and the belt does not falter. Where could be the problem?180238

Viktor Voroncov
01-29-2011, 7:52 AM
1) Mechanical contact - check all belt length, may be somewhere something fall on belt
2) I see really too much dust on picture - clean laser every day, especially if you use cheap chinese rubber for stamps
3) Any PVC cutting/engraving? May be you have worked with unusual materials, and can't guarantee that this materials do not contain PVC? Any cheap chinese laiminates/Graphlux? Picture is not good but metal item in right bottom corner looks like rusted?

Chuck Stone
01-29-2011, 8:11 AM
if this were happening on my laser, I'd start looking at the places the belt will
be in contact with other parts, namely the pulleys at either end. For you to get
this edge damage I think there would need to be some sort of mis-alignment of
the belt and pulley. Could be a problem with the pulley itself, the pulley shaft,
any bearings that allow it to move etc. It could also be a bracket that holds
the motor assembly or pulley. Perhaps a screw came loose and the unit is now
canted at an angle? As the belt moves through it, it would be able to catch on
the edge of the pulley, the bracket, rails etc. Could be as simple as a worn out
bushing that's allowing the alignment to change.

If you move the rail by hand, look to see if/where the belt is rubbing. It shouldn't
be too hard to track down.

Dan Hintz
01-29-2011, 9:52 AM
I don't know what you're cutting, but you need either a better vacuum system, better air assist, or both. That belt is filthy! All of that stuff is being transferred to your pulleys and is causing undue wear, even if it's not the cause of your belt failure. Your belts should be a solid black with no contamination.

Make sure the pulleys are in line with each other, and make sure there are no missing teeth. Check the inside top of every pulley and make sure the lip is smooth.

Robert Walters
01-29-2011, 1:36 PM
The system is way too dirty as other have already mentioned.

Make sure that when you install the belt, you are applying even tension when clamping.
If you can't place one or two fingers behind the belt easily, it's too tight.

Does the belt fray always on the same side? If so, that could be an alignment issue.

Have you ever replaced one of the pulleys/bearings before?
If so, one may not be exactly the same and causing misalignment and pulling the belt to one side.

Nigel Morgan
01-29-2011, 10:13 PM
Hi,

My belt used to do this all the time for what reason I don't know, what stopped it is, I place 3 small thin washers under the X motor mounts, runs fin now.

Nigel

Zlatko Kursar
01-31-2011, 8:50 AM
This is a picture in the middle of the day (I make about 20 rubber stamps a day) and that is why it is dirty.
Viktor, when I start with laser job (2005) unfortunately I cut PVC because my Epilog seller didn't tell me that I should not cut.:mad:
I checked all pulley, but I don't see any problem. I never changed the pulleys.
Nigel, I will try your solution.

Viktor Voroncov
01-31-2011, 8:58 AM
What you can tell about your rubber? Made in China? Do you feel small sand after engraving?

Zlatko Kursar
01-31-2011, 10:41 AM
On the rubber is written "SPECIAL RUBBER FOR LASER ENGRAVING" and there is an "Q" in circle.

Viktor Voroncov
01-31-2011, 11:29 AM
Where rubber made? China? How it smell - no odor at all, reasonable, disaster? may be Longstar?? :)

Uma Duffy
02-01-2011, 3:26 PM
The problem is with the pulley on top of the servo that drives the belt its to low on the shaft. We went through 4 belts on our epilog before it was figured out. you can fix this by removing the motor-pulley unit and prying with a small screw drivier raising the pulley enough to let the belt ride center. now your pulley is forcing your belt to ride high just enough to fold and tear when in contact with the machine or pulley head. when you get the servo off you can see the wear from the belt on the pulley and how much it needs to be raised for the belt to ride center. we did it with out bending the shaft just enough force to raise it to where it should be.. our machine was new and it was frustrating to say the least. good luck.

Zlatko Kursar
02-02-2011, 8:12 AM
Thanks Uma for information. I will try this solution.
Victor, I don't now where is rubber made. There is no odor.

Rangarajan Saravana kumar
02-02-2011, 8:36 AM
Hi,

We initially had similar issues and changed belt three to four in a year.

Epilog had come up with a solution of replacing the x motor pcb and its circuit

pl call the local tech support if your machine is not updated

Rgds,
Saravana kumar

Viktor Voroncov
02-02-2011, 1:59 PM
Zlatko,
1) Remove rubber from possible problems list :))
2) Agree with Uma concerning unproper pulley position - just came from customer - same problem was on his laser.

Robert Walters
02-03-2011, 2:23 PM
Zlatko,


Using a dial caliper or feeler gauge from auto parts store, I would check the height of the belt at each pulley and at the point it connects with the lens assembly.

If you have plastic pulleys, they can wear out.

If the shaft the pulleys are on have been bent, that could cause the belt to pull to one side and cause wear.

Frank Corker
02-03-2011, 3:18 PM
That is definitely catching on something. Both the Helix and the mini have sides that can be removed (carefully obviously) just follow the belt around.