So I'm having an issue with one of my M200s. As you'll see from the photo's I'm having layer displacement issues. I've followed the directions for "Eliminating Axis Issues: http://support.zortrax.com/eliminating-axis-problems/" and it did not solve the problem. All the pulleys are tight, belts are tight and there doesn't seem to be any binding when I move the extruder around. What the hell is going on?!
In the video below you'll hear the belt skip at :38. Also you can see the evidence in the photos. Suggestions?
It's hard to say really, usually axis maintenance does the trick. You can try turning off the printer and move extruder using hand around build plate to see if there is any resistance during that. Could be like Aleksiej said - faulty stepper motor or bent guides.
I'm going to go through the axis maintenance one more time to triple check. At the same time I want to visually see the problem. It for sure sounds like the belt skipping but I haven't actually seen it. I guess it could be the motor. If that's true, I'll pull the motor off my other M200 to test.
So chew on this. Before I attempted the axis maintenance, we started a small print multiple times so we could see the issue. The first two times it skipped but only after the actual printing started. It did not skip during initial calibration. Then on the third print, it didn't skip at all – printing perfect. This happened yesterday as well but I didn't recognize it because I stopped the print due to an error (I forgot to add supports).
It really makes me think it's the stepper motor or something else. It doesn't bind any other time other than when printing, by that I mean during calibration or pre-print calibration. Bizarre.
FYI, I did run the same print in my other M200 with no issues.
In the years of running maintenance/repair on printers I have only ever had to replace two stepper motors, it is not likely the motor is the issue. More often then not the cable is shorting out or the connector is bad. Rather then removing the motor I would take the cables off of the good printer for the Y axis motor and swap them out. Chances are that will solve the problem, and if it does not then try the ribbon cable (this sounds stupid but it has worked a few times for some reason).
An engineer here was slicing a part for our UP Plus printers and was spinning the view and model araound during the slicing so the slices printed perfectly but spread out like playing cards.
Is there any possibility you moved the part in the slicing software during the slicing procedure, using the move command in the Zortrax software while the status bar at the bottom is still moving?
Try slicing the parts again but be sure not to touch the mouse or keyboard until it is completed.
Thanks for the replies. It's 100% not the software. I can get it to print perfectly on my other M200..... and on this one now. I have run four prints this morning while filming it and I cannot get it to displace the layers. It's printing perfectly now.
At this point my conclusion is either the cable or the motor. Since I can't get it to replicate the problem again, I'm screwed. I'm going to pull the cable and check for continuity while bending it around but I think I'll order another cable to be on the safe side and hope that was it. I'm running another print now and hopefully it will happen again. My fear is being in the middle of a 22hr print and having it do it again. That's what happened this weekend.
Always good when the individual posts the fix to the problem, helps others on here out!
Quite a few threads on here with no conclusion to the problem....... not much use to anybody really.... but then again maybe they never got it sorted out?????
Your gears on the linear rods are slipping when the motor turns the belt.Turn the machine off and look at the individual gears and move the head in the affected direction. When moving the head, grab the belt and attempt to hold it still. The linear rod should continue to turn while the belt does not. This is an updated idea of what I thought the problem was. Since my last response I found this was also a problem that can occur.
Ok, so yesterday I said it's the cable. Now, I'm not so sure. I switched the cables on my two M200. I printed two prints on each machine. The machine with the "bad" cable started displacing layers. It had never had that issue. The machine with the "good" cable printed two perfect prints.
Now I focused on getting my current job I needed printed on the "good" cable machine. Layer displacement again!!!!. Stop the print, try again....same result. Third print started to look good. About 7ish hours in, layer displacement.
This is killing me. I thought I figured it out. The machine that never had layer displacement issues started having issues as soon as I switched cables. What the hell!!!
Your gears on the linear rods are slipping when the motor turns the belt.Turn the machine off and look at the individual gears and move the head in the affected direction. When moving the head, grab the belt and attempt to hold it still. The linear rod should continue to turn while the belt does not. This is an updated idea of what I thought the problem was. Since my last response I found this was also a problem that can occur.
-NS
I'm a little confused here. What gears on the linear rods are you talking about? I've gone through and tightened every pulley with gears on it. None of them slip. When I move the print head back and forth, the belt moves the rods which in turn moves the motor. If I grab on to the belt and hold it tight and try and move the head, I move the belt which moves my hand, etc.
Is it possible to shoot a couple pics or video of what your'e describing? Both of my printers are down and I have jobs to print. I need to figure this out. I'm at a loss.
Ok, at this point I've gone through and checked all connections again and tightened all the geared pulleys I can find. I've also made sure all the belts are tensioned about the same. I've included a pic of the geared pulleys so that there is no confusion, cause we all know I'm super confused at this point!
If there's anything anyone can think of that I missed, please let me know. I'm starting a print with new Zcode. We'll see how it goes.
If that still doesn't fix it.. Have you removed belts from both motors and tried to move extruder head by hand to check for binding? If you move it with belts still on motor pulleys, you will get resistance from motors and might seem harder than it should. The sound in the video almost sounds like a stepper motor missing some steps because of binding or resistance. It appeared to happen on a rapid movement which is when steppers have the least amount of torque.
The few times I've had shifted layers, greasing the rods has solved the problem. Also, and a bit of a long shot, you might want to try firmware 008, which i think had slower acceleration on some moves.
If that still doesn't fix it.. Have you removed belts from both motors and tried to move extruder head by hand to check for binding? If you move it with belts still on motor pulleys, you will get resistance from motors and might seem harder than it should. The sound in the video almost sounds like a stepper motor missing some steps because of binding or resistance. It appeared to happen on a rapid movement which is when steppers have the least amount of torque.
I have checked for binding. That's what I thought the problem was initially, it made the most sense to me. I went through the "eliminating axis" procedure and then moved the head around a few more times to make sure it moved freely. I also moved the head around the print area with the motors off to make sure there was no friction.
You are correct on that it only happens when it does a quick movement. Yesterday when I was prepping my ZCode, I noticed that the "fast"button was checked. I never print anything on fast mode. I must have clicked it inadvertently running all these test. I unchecked it for the two test I ran yesterday, after I checked all the gear pulleys and they both worked flawlessly. Also, I only ran two complete prints, one 2hr and one 8hr but I started about 10 jobs to see if the error would replicate itself. It never did.
The few times I've had shifted layers, greasing the rods has solved the problem. Also, and a bit of a long shot, you might want to try firmware 008, which i think had slower acceleration on some moves.
I greased the rods but the firmware thing makes sense. As Kyle noted, it only seems to happen on fast moves and like I said, I think I inadvertently had it on "fast". If it happens again, I'll go down in firmware and see if that changes anything. I'm going to go read the change log on the last few firmware updates!
Ok, after repeated tests, I can confirm it only displaces the layers when the ZCode has been written with "fast speed" on. There is still obviously something going but I can't figure out where the problem is. I've tightened every gear pulley possible and checked anywhere the belts could slip. It's not a huge deal because I rarely ever used fast mode, even these times it was on by accident.
So to wrap up, and I mean it this time....I hope, if you're having this problem, check your gear pulley set screws and make sure "fast" isn't clicked for speed.
You might have some garbage in the stepper itself. They have very tight tolerances inside and the smallest piece of metal stuck to one of the magnetic surfaces could cause this.. Just keep using normal speed.. :D
