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darsan

Ultimaker 3, printer head slamming into corners and clicking

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Hi folks

 

Been scanning the forum but havent found someone that seems to have the same problem as I do (if it is a problem).

 

The printer is new, and made this sound out of the box, but I'm pretty sure it's not a normal sound.

 

 

https://www.dropbox.com/s/66djuu4955x4i4c/20180411_113325.mp4?dl=0

 

1. Is it normal?

2. If not, any suggestion on what might be the cause of it?

 

 

I've tried printing, and it shows no issues in the prints as far as i can see. The sound is only produced at the beginning of the prints (when it seems to reset or go rest in the corner). Prints with dual extrusion works well aswell.

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Hi @darsan, thank you for your post and welcome to the Ultimaker community! 

It looks like your Ultimaker is not detecting (in time) that it has reached the frame. There should be end stops in the (on the video) top left corner which should send a signal.

It works like this, the print head reaches the corner and the axles that protrude the print head trigger a lever under the frame (of the end stop), and that is how it knows its position and sends a signal to stop moving in that direction.

 

The sound you hear is not really damaging your Ultimaker, it is 'just' the stepper motor skipping some steps, so you shouldn't necessarily be worried about that. Although of course you want to have it fixed, I understand.

 

The problem is most likely that either the end stop has moved slightly and the lever is pressed just a fraction too late (can happen during shipment), or it got disconnected at the electronics. Could also happen during shipment, but less likely.

 

We can test this in various ways, you can move the print head manually to that side of the frame and listen carefully if (and when) you hear a small click. You should hear it before it hits the frame. If it is difficult to hear, you can park the print head in the opposite corner and have it move to its home position. Before it has reached the frame you have some time to manually press the end stop, either with your finger or a pen or whatever. The printhead should immediately respond upon you pressing the lever. If it does, it is probably misaligned and you should be able to unscrew it, reposition it and screw it back. You could try it again and see if it works. 

 

Alternatively, you could try and bend the lever oh so slightly, so it is being pressed sooner (and thus, your print head won't hit your frame anymore). I would not do this at first, because if you use too much force you could break it and then you need to wait for a new end stop to arrive. 

 

Good luck! 

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https://www.dropbox.com/s/c8y1uhsvnu5drat/20180411_121720_001.mp4?dl=0

 

 

I tried moving it, but it is such a snug fit that it wasnt possible to shift the trigger and its lever more than a fraction of a millimeter when unscrewing it from the side of the UM3.

Bending the lever was however quite easy, so it now clicks alot sooner. The problem still persists tho.

 

Watch the movie above.

 

07:560 - the lever snaps back: "printer head not in corner"

08:950 - the lever clicks again: "printer head in corner"

10:300 all the way to 11:000 - the printer head slams into the corner three times.

 

 

So it either does not register the trigger, or it registers too slow. If the sensor cables are disconnected, will it stop trying to slam the corner like now, or would it keep trying to get in in for a longer time? The reason im asking and not checking is that it seems that i need to disassemble a bit to check that ;)

 

 

It also appears something is being grinded, as dust particles appear:

https://www.dropbox.com/s/qjbgzoduwr00rw2/20180411_122603.jpg?dl=0

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Did you check both end stops? There is one detecting proximity for each side of the frame. 

 

Did you try to park the print head in the opposing corner and manually trigger the end stop? Did it influence the movement?

On one side, I would expect it to because if the printer would get zero signal, it could try to move 'through' the frame a few seconds longer. 

Which is also an answer to this question:

27 minutes ago, darsan said:

If the sensor cables are disconnected, will it stop trying to slam the corner like now, or would it keep trying to get in in for a longer time? The reason im asking and not checking is that it seems that i need to disassemble a bit to check that 

 

If you move the print head in the opposing corner and manually trigger the end stop, if it does not influence the movement, your end stop is either broken or disconnected at the PCB. If it does influence the movement, it appears it is still triggered too late. 

 

The dust you see is not really related to what your experiencing with the end stops. It looks like 1 pulley could be repositioned slightly better so the belt fits in the middle of the pulley better. There should be a tiny set screw on the pulley, which allows you to relocate the pulley slightly. 

 

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10 minutes ago, SandervG said:

If you move the print head in the opposing corner and manually trigger the end stop, if it does not influence the movement, your end stop is either broken or disconnected at the PCB. If it does influence the movement, it appears it is still triggered too late.

 

 

It does not influence movement. Checked the PCB board and it was very well connected, so it seems the limit switch is broken. Do i contact the reseller?

 

 

And thank you for the very quick replies, much appreciated!

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Yes, in that case it is likely that a wire broke during shipment. It would be recommended to contact your reseller yes.

One final check to potentially save you some time/hassle, when pressing the end stops manually did you trigger the correct end stop matching the movement?

For example, if the print head moves (lets call it vertically from top down view), did you press the corresponding end stop, which should prevent the head hitting that side of the frame?

If it would travel in a straight line, and you would hit the other end stop, protecting the left side of the frame, it indeed would not influence the movement (if I am not mistaken).

Just checking. If that indeed matches your test, you should contact your reseller.

 

Good luck! 

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Nevermind. The dust visible was the belt touching the cable from the limit switch, which had made it come loose just a tiny bit. As soon as i unscrewed the switch and as soon as i touched the shrink tubing the whole cable came loose from the switch.

 

I tried the "home" button with the cable completely loose and it now tried a few times more and then produced the error message E17, so i bet that before i unscrewed it it was actually veeery close, intermittently touching the connection with the switch and after a few times crashing the corner it produced enough of a signal to say "im at the end now" (since i never once had the E17 message before).

 

Ill try soldering it up tonight, and will try to tape it to the side so that it wont come in contact with the belt again.

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That did it. The cable wasnt worn down through the tubing, but more likely been pulled by the belt very slightly back and forth until the soldering came loose. Re-soldered it (sounds easier than it was in that tight corner and with my lumberjack hands, since the cables were about as long as they needed to be) and then bent the cables slightly towards the chassi so that the belt cant touch them again. No more trying to shove the printer head through the back of the machine :D

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Hi again

 

Ah, just saw your post. Wish i had seen it 30 minutes ago. I believe i did cause a problem with the slight bending of the limit switch earlier. This caused the limit to come too soon, which i thought wouldnt matter at all since i'm not trying to print anything on the farthest out piece of the print bed. But today i watched the printer as it printed and realised that it used an external "switch flipper" to change the print core up and down. This did in fact not work very well, and i believe that me bending the switched caused this (the printed head thinking that is was further back than it really was). I did however bend the switch back again before seeing your post, and when i did the diagnostics just now the testing of the switching worked very well. It looked alot more solid than on the printing done today. Wish i had tried that before to see if it really did fail some times, or if it was me mis-judging the print.

 

 

 

I do however experience a new type of problem now, when doing a bit taller prints. I am currently prototyping some enclosures (OT bragging: for a gateway we've constructed, for a startup im running with a friend (http://www.d-rail.se/)).

 

This has failed two times today, due to layer shifting. The shift has come on the same part of the same print, but on very different heights (one being close to the build plate and this one being much further up: https://www.dropbox.com/s/9n9qcft7axsgqcv/20180413_202953.jpg?dl=0

Checking the belt tension by hand. You can hardly press the top belt all the way down to the bottom since it is very tense, but the bottom belt is very loose: https://www.dropbox.com/s/mkjyfqb7e2rbsv4/20180413_202600.mp4?dl=0

Using the diagnostics tool you can see that the front belt on the lower part is wobbling wildly. The back belt feels alot more tense. https://www.dropbox.com/s/mkjyfqb7e2rbsv4/20180413_202600.mp4?dl=0

 

 

Could i try to pull the belt one or two tooths on the pulley, or loosen the screw and adjusting so that the "loose tension" is divided evenly on the top and bottom part of the belt? Or do i risk causing some problem doing so?

 

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