Problem setting up core XY
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@william3d When I had a somewhat similar issue on my CoreXY it turned out that one of the pulleys on the motors was slipping.
In order to move in X (or Y) only, a CoreXY has to move both motors evenly. If they aren't moving the belts the same distance on each request then the move will not be just X or Y and you'll get what you're seeing.
Just a thought.
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@william3d I'm not sure what it means when you say X and Y are moving correctly - does that mean it's OK during homing and then it gets weird only when you try to do other moves? When you home X does the carriage move only in the X direction, and when you home Y does it move only in the Y direction?
Some possibilities come to mind...
- loose drive pulley(s)- inspect
- not operating in corexy mode- config looks OK
- different size pulleys on the motors - inspect carefully
- bad cable/connector to motor(s)- inspect thoroughly
- bad driver chip- try swapping another driver
- extremely bad layout that lets belt slip on pulley(s)
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@mrehorstdmd When I say moved correctly I have a Macro created for Test movement
Test for the correct X motor movement by sending these commands from the console:G91
G1 H2 X10 F3000
If the head moves diagonally in the +X and +Y directions, all is well. If it moves in the -X and -Y directions, change the S parameter to S1 in the M569 P0 command. If it moves towards +X and -Y, or towards -X and +Y, then either turn the power off and swap the X and Y motor connections, or use M584 in config.g to swap the X and Y motor drivers over.When you have the X motor moving correctly, test the Y motor by sending from the console:
G91
G1 H2 Y10 F3000
If the head moves diagonally in the +X and -Y directions, all is well. If it moves in the -X and +Y directions, change the S parameter in the M569 P1 command to S1. [Different rules applies to firmware 1.18 and earlier].Important: make sure that you have chosen a right-hand axis system. That is, looking down on the printer the +Y direction should be 90 degrees anticlockwise from the +X direction. If instead it is 90 degrees clockwise, you have a left-hand axis system, which will give you mirror-image prints.
head moves diagonally in the +X and +Y directions
head moves diagonally in the +X and -Y directionsI thought I was onto it I had replaced the motors with the different ones that were different .9 and 1.8 deg So I just put the originals back in that are the same motors on both sides problem still exists.
Some possibilities come to mind...
loose drive pulley(s)- inspect DONE
not operating in corexy mode- config looks OK DONE OK
different size pulleys on the motors - inspect carefully DONE CHECK
bad cable/connector to motor(s)- inspect thoroughly DONE CHECK
bad driver chip- try swapping another driver SWAPPED BOARDS STILL THERE.
extremely bad layout that lets belt slip on pulley(s : Would not think so created a BLV mgn Cube WITH CNC parts. -
@markz That was a good thought I realized I change motors in an attempt to solve problems and put in two different size motors Presented the same problem. Change back to two a day at home motors still have the problem.
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So it works fine using your test commands, and it homes OK. Does it screw up if you give it a file to print?
Are one or both motors skipping steps? Sufficient/excessive motor current?
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@mrehorstdmd after changing the M208 do I have to set offsets in simplify3D as well, or does it read the firmware's settings for origin? That's where I'm getting confused on the subject.
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i am missing test without the H2 command to check correct x and y movements
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@william3d said in Problem setting up core XY:
G1 X100 Y100 F6000
G30You should have a G90 before that G1 command in your homeall since you want to place the probe in absolute space.
Are you sure this is actually a CoreXY printer and not a cartesian? It is a BLV cube?
Can you show a video of the behaviour?
With the belts disconnected from the motors are you able to move the print carriage around by hand smoothly? With the belts connected are you able to move the print head around slowly and smoothly? Does the resistance feel even in both X and Y?
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@william3d Feel free to ignore this if too basic but here's my 2c ->
When I was having strange issues with my CoreXY the first thing I did was check simple movement. [I did try to use homing as an early test, immediately drove the nozzle into the bed and thought hmmm...]
Homing is an extreme test because it causes parts to hit other parts and limit out.
Instead, I placed the head in the center of the bed and turned off homing requirements then used the dashboard to move the carriage left and right and back and forth 50mm at a shot. Make sure only the dimension you expect to move actually changes when you do that.
Once moving straight was true everything else worked.
Mark
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@mmartin I'd be very surprised if S3D can read the Duet board's firmware. You'll have to enter offsets, and different slicers may require different offsets depending on how they reference the home position (?). This sort of issue is one reason I prefer to use the center of the bed for the origin- it seems to be very easy to set up in different slicers.
Can you post a picture of the printer's XY mechanism?
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@mrehorstdmd I installed Cura last night and am having much better results with the prints / compatibility of the software. My main issue is I'm not sure what settings are being controlled by the firmware and what settings are being controlled by Cura. Example: Does Cura automatically use my bed leveling mesh or do I need to run it in the starting Gcode?
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@mmartin Someone else will have to help you with that. I don't use autoleveling, and I operate the printer using the DWC or Panel Due.
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Here are static photos of the machine and the setup of a BLV CUBE. I am working on videos of the problem
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One thing that's obvious from the first photo is that the belt running from the left end of the X axis to the extruder carriage (fixed with a purple zip-tie) is not parallel to the X axis guide rail. Are you sure the belt is anchored to the right spot on the carriage? Can you take a picture looking down on the machine, showing the entire corexy mechanism?
That type of error will at the least cause belt tension to vary with the extruder carriage position, and may create more problems than that depending on how far out of parallel it is. If you tensioned the belts and movement makes them get tighter, your motors may skip steps because the tension becomes too high. It's also possible for belt to slip on the drive pulley if the tension goes the other way when the extruder carriage moves. The belt tension should be constant no matter where the extruder carriage is in XY space. That is accomplished by keeping the belts parallel to the guide rails. See: https://drmrehorst.blogspot.com/2018/08/corexy-mechanism-layout-and-belt.html
Was that a kit? Make sure you assembled it correctly, and if it's right, I suggest you demand your money back!
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@mrehorstdmd said in Problem setting up core XY:
if it's right, I suggest you demand your money back!
the original blv had a slight problem with that. but in this kit its very bad.
there is an original metal kit
https://www.aliexpress.com/item/1005001323243487.html
that does not have that problem -
@Veti I was wondering if there was a problem with the parts I purchased from a supplier in China BLV Does not promote that supplier anymore.
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Does @mmartin == @william3d or are there two different machines/problems/people here?
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A lot of great comments and information and I appreciate the time that everyone is put into helping me solve this issue. I'm continuing to read through and try everything everyone said I am continuing to have the same issue where I cannot move either X or Y By themselves The web controller shows example X25 Y25 I move to X25 Y200 The web controller shows X25 Y200 but You can tell X has moved to 150 and Y is at 200.
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@william3d
can you post a picture of the x carriage from the side.
