CoreXY - X-Axis Vibration Issues



  • It's definitely something I can look at. I will have to model some sort of clamp for the rail. How does it stay "square" if it is allowed to move?



  • its allowed to move in one direction to counteract slight alignment issues but it can not rotate.



  • I think I understand, I am trying to look at your thingiverse link but the site is sooooo slow a the moment!



  • @veti OK! So I have created a quick and dirty solution! I am going to print it in a few minutes and we will see if that solves the issue!



  • @veti So unfortunately it didn't help. My solution wasn't perfect by any means but it didn't change at all. Hmm... any other ideas? I know without the belts in ran perfectly, so it's obviously being pulled by the belts (as I understand is pretty normal with corexy).



  • @syko_symatic Difficult to advise without a bit more information. All we know is that it's a CoreXY. Can you post some pictures -especially showing the belt arrangements. A bit better description of the problem would also help.

    Without having much to go on, I could make a shot in the dark and say that it might might be uneven belt tension that is imparting a twisting force which in turn is causing the guides to bind. The "classic" CoreXY belt patter usually shows the X carriage belts being quite a distance either side of the centre line of the X carriage. So if your belts are aligned like that, and the tension is uneven, then you might be getting a twisting force, which might be causing the guides to bind. I use stacked belts running along the centre line of the X carriage but you may not be able to do that easily.



  • also check that there is no twisting of the belts on direction change.
    i.e make a gcode file with rapid 5mm movement back and forth at high speed and look at the belts during this.



  • @deckingman Thanks, I will try and add some more info.
    The belt arrangment is stacked and looks almost exactly like e3d's tool changer machine. I have included a short video from the other night. The noise isn't an issue in that video as it doesn't occur until it's moving a little faster.

    Link

    I have tried increasing and decreasing belt tension to no avail. Could it possibly be motor setting related?



  • create a gcode that can replicate the noise.
    Then while its making the noise try to narrow down the location.
    the frame looks like it could be resonating at certain frequencies.



  • @veti It definitely sounds like it's coming from the x-axis carriage. I am going to give tuning the acceleration and max speed a go. Any suggestions of a good starting point?



  • Is the X axis linear guide a "preload" type? How is the X axis rail mounted so that it can slide? If it is free to move, it may be free to rattle, depending on how it's mounted.



  • how stable is the x carriage? Push the nozzle in different directions and see if there is play.
    Also check the fans. I had some fans that created a rattle caused by the blades moving inside the fan at higher speeds. and banging on the casing



  • @mrehorstdmd yes it’s preloaded. It is secured to a cross-brace by a few cap head screws.



  • Hi,

    It's hard to tell from the video but are the belts on either side of the X slide parallel to the slide?

    Frederick



  • @fcwilt as best as I can get them. I’m going to try re-aligning everything again. Annoying, but I am going to wait for some new gates pulleys from E3D to make sure everything is the best it can be.

    Or maybe I will re-align it all first? I can’t decide. Either way I will keep trying.



  • @syko_symatic

    Well I think it has to be something about your build.

    I built a D-Bot CoreXY printer and it has no binding issues at all. BUT it uses wheels-on-extrusion tech, not slides.

    My next CoreXY will try slides.

    Frederick



  • @fcwilt my thoughts exactly hence the slight rebuild. At least I can do it by only removing the top plate!



  • @syko_symatic just press f5 untill it loads ...



  • @fcwilt Having a think about it, the E3D design uses the fabtotum style corexy which places the belts in front and behind the x carriage. It is technically possible to move them both behind the carriage, would that help?



  • @syko_symatic said in CoreXY - X-Axis Vibration Issues:

    @fcwilt Having a think about it, the E3D design uses the fabtotum style corexy which places the belts in front and behind the x carriage. It is technically possible to move them both behind the carriage, would that help?

    It might. But moving both belts to the centre line of the X carriage would be better - as per my post of 12th Feb above.


Log in to reply