Core XYUV configuration

pcsentinel

Please can I get some help with a CoreXYUV configuration.
I am just starting to commision this and have already stumbled.
The first test configuration is just to get the corexy movement working. (I'll move onto the UV afterwards)
The motors are mounted at the rear of the frame.
After going through the help on https://duet3d.dozuki.com/Wiki/ConfiguringRepRapFirmwareCoreXYPrinter
The Rear left motor is connected to the Y MOTOR connection and the Rear Right motor is connected to the X Motor connection.

I have the following in config.g

;Movement
M669 K1 ; switch to CoreXY mode
M569 P0 S1 ; X Drive 1 goes backwards
M569 P1 S1 ; Y Drive 1 goes forwards
M569 P3 S0 ; E0 Drive 3 goes forwards
M569 P8 S1 ; Z Left Drive 8 goes forwards
M569 P9 S1 ; Z Right Drive 9 goes forwards
M584 X0 Y1 Z8:9 E3:4; assign drives to axis

When I run the 2 tests from the web page with the above settings then the movement is as expected.
G91
G1 H2 X10 F3000
Moves the head in the +X and +Y directions

G91
G1 H2 Y10 F3000
Moves the head in the +X and -Y directions

The problem comes when I just want to run normal movement
So if I just issue a normal move command i.e. move head in the X direction 10 mm with
G91
G1 X10 F3000 S2
then the carriage moves diagonally and not just horizontally.

If I use
G91
G1 X10 Y10 F3000 S2
then the carriage moves in only the +X direction

If I use
G91
G1 X10 Y-10 S2
then the carriage moves in only the +Y direction

Also, if I use absolute moves
say the axis positions are being reported as X55 Y30
and I issue
G1 X45 Y20 S2
The head moves -X -Y direction but the new reported postions are X32.50 Y12.50

I am completely confused.

Any help?

fcwilt

Hi,

Why do you have that S2 parameter? That is the old name for the H2 parameter and it does the same thing when not in LASER mode.

Frederick

pcsentinel

Thank you for the response, but that using H2 instead of S2 doesn't solve the movement issue.

The problem remains that when instructing an X only move G1 X10 then the carriage moves +X+Y

Veti

@pcsentinel said in Core XYUV configuration:

S2

H2 Individual motor mode. X refers to the X motor, Y refers to the Y motor, and so on. Normally used with relative motor coordinates (see G91).

you do not want to use that for corexy

pcsentinel

Hi Veti, thanks I was actually writing a response when yours came through. It was my lack of understanding. I was using the S2 or H2 command to ignore endstops as I am just commissioning at this stage so don't have any fitted yet. So when you enter G1 X10 S2 when the head is at 0,0,0 then I was expecting a positive X movement only. when I set M564 H0 instead then G1 X10 does exactly what it should. My bad!

fcwilt

@pcsentinel said in Core XYUV configuration:

when I set M564 H0 instead then G1 X10 does exactly what it should. My bad!

Just so you know if you issue a G92 command like G92 X0 Y0 that tells the firmware that the nozzle is positioned at X=0 Y=0, regardless of where it actually is.

It also marks each axis as homed.

A M18 command disables all the motors and marks each axis as not homed.

Frederick

o_lampe

Hi @pcsentinel
I've gone through this lately and I have steppers which fit the duet headers in both directions!
I tried all possibilities systematically. Otherwise you only run in circles...
Mark the stepper cables with L and R
Then go through all 4 variations in config.g to reverse the stepper direction with M569
0-0
0-1
1-0
1-1

You can write a macro

G92 X0 Y0
G1 X10 F50 ; very slow so you can observe 
G1 Y10
G1 X0 Y0 ; ready for the next test

Before you run the macro, make sure the print head has enough room all around.
If it doesn't move as expected, change the M569 setting in config.g, reset the printer, when asked and repeat the macro.

If none of the 4 options work, switch off the printer and switch L and R steppers. Turn on the printer and go on with the 4 M569 options.

pcsentinel

Hi, thanks for your help, very useful. movement is all sorted now, but issues with homing, please see
https://forum.duet3d.com/topic/21391/core-xyuv-homing-going-squiffy