BTT Octobus max ez 1.0

[McCosch]

Hello,
I tried again to install the Bigtreech Octobus Max EZ board in a Voron2.4. Now I'm setting up the X;Y axes, but unfortunately I can't get it right. I changed the direction of rotation in "dir_pin" without success. Either the X axis runs correctly, then the Y axis runs in the other direction and vice versa. You can rule out that the connection cabling is not correct because it has already run in this connection setting, but with an Octobus pro board. What should also be mentioned is that both axes run at the same time when I select the home function, for example X.
I would be happy if someone could help me with this.

07.03.24.zip

[Glengus]

Have you seen this picture? It's from the voron setup guide.

[McCosch]

I know that and have tried it, without success.

[Glengus]

That sucks, sorry to hear

[Crashdown]

In my config neither X or Y stepper is ! on the dir pin

you seem to have ! on dir pin only on stepper X (motor 1)

Edit: Though from memory I had to invert mine when I changed to using 5160 drivers so if you are using 2209's they might both need to be ! on dir pin

Also: What do you mean by "both axes run at the same time when I select the home function"? Do you mean the toolhead moves diagonally when you home X? If that is the case it would mean one of the motors is not working because both motors need to turn to move the gantry in X or Y

Edited March 8 by Crashdown

[McCosch]

10 hours ago, Crashdown said:

In my config neither X or Y stepper is ! on the dir pin

you seem to have ! on dir pin only on stepper X (motor 1)

Edit: Though from memory I had to invert mine when I changed to using 5160 drivers so if you are using 2209's they might both need to be ! on dir pin

Also: What do you mean by "both axes run at the same time when I select the home function"? Do you mean the toolhead moves diagonally when you home X? If that is the case it would mean one of the motors is not working because both motors need to turn to move the gantry in X or Y

Hello,
could it be possible that the error could be that there is a difference in the motor connections from Octobus pro to Octobus max. As you can see in the pictures, the order of the PINs is different. I wrote that I swapped the board but I didn't change the rest, like the plugs. Could the error be in the movement of the motors.

[SirDangalf]

Hi McCosch,

octopus max ez 1.0 is working fine in my voron 2.4

Here are my a/b settings (as a sidenote B is motor 3 and A is motor 4):

 

#*************************************************************************************
# X/Y-Axis
#*************************************************************************************

# Motor-3
[stepper_x]
step_pin: PE1
dir_pin: !PE0
enable_pin: !PE2
rotation_distance: 40
microsteps: 32
full_steps_per_rotation:400
endstop_pin: PF0
position_endstop: 335
position_min: -10
position_max: 335
homing_speed: 50
homing_retract_dist: 5
homing_positive_dir: true

[tmc2209 stepper_x]
uart_pin: PG12
run_current: 1.250
#interpolate: false

# Motor-4
[stepper_y]
step_pin: PB8
dir_pin: !PB9
enable_pin: !PB7
rotation_distance: 40
microsteps: 32
full_steps_per_rotation:400
endstop_pin: PF2
position_endstop: 333
position_min: -12
position_max: 333
homing_speed: 50
homing_retract_dist: 5
homing_positive_dir: true

[tmc2209 stepper_y]
uart_pin: PG11
run_current: 1.250
#interpolate: false

Perhaps this helps.

 

[McCosch]

Thanks for the info, I'll try it out.

[Methos]

There are two phases to fixing a CoreXY: swapping the stepper connections IE X to Y or Y to X and then you adjust the direction pins.

[Crashdown]

8 hours ago, McCosch said:

Hello,
could it be possible that the error could be that there is a difference in the motor connections from Octobus pro to Octobus max. As you can see in the pictures, the order of the PINs is different. I wrote that I swapped the board but I didn't change the rest, like the plugs. Could the error be in the movement of the motors.

 

No I don't believe so. I think they just changed their naming scheme for the stepper phases. As far as I have ever seen the connectors always have one phase on one side of the plug and one phase on the other side. So for octopus they called them A phase and B phase and on the max ez they named them phase 1 and phase 2. If the wiring was changed that would mean one phase was the center two pins of the plug and the other phase was the outer pair of pins. That would mean the Octo max ez would not match the wiring of any other printer board. BTT didn't provide any special wiring diagram and I didn't wire mine in any special way.

 

I would suggest providing a video or at least pictures of what the problem is that you are experiencing.

 

It really sounds like you have the A and B stepper motors swapped. If the x axis homes correctly but the y axis moves in the wrong direction the steppers are swapped. If you invert ! both dir pins and the x axis moves in the wrong direction and y axis moves inthe correct direction that also means the steppers are swapped. That's why you can't just invert both direction pins to solve it, and Inverting ! only one of the dir pins will just swap X axis movement to Y axis movement and vice versa.

I would try using the stepper buzz commands to identify which motor is turning and what direction

https://docs.vorondesign.com/build/startup/

 

For Voron 2.4 and Trident:

Both motors clockwise moves carriage to the right as seen from the front of the machine

Both motors anticlockwise moves carriage to left as seen from front 

A motor clockwise, B motor anticlockwise moves carriage towards front away from motors

A motor anticlockwise, B motor clockwise moves carriage rearwards towards motors

Edited March 9 by Crashdown

[Crashdown]

If swapping the wiring for motor A and Motor B solves it and you are sure you had the motors connected to corrrect drivers then it means the motors are turning the wrong way. You can solve that by swapping 2 pins on either side of the connector, left or right. eg pin 1 and 2. But swap the same pins on both A and b motor connectors. Or, you swap all the pins around, pin 1 to 4, 2 to 3 etc by flipping the plastic part of the connectors 180 degrees.

Then you can put the connectors back to the 'standard' Voron 2.4 wiring layout if that is important to you

If that all works then yes that would seem to mean there is a difference between the octopus pro and the max EZ like the stepper plug wiring is flipped 180 degrees 

Edited March 9 by Crashdown

[McCosch]

6 hours ago, Crashdown said:

No I don't believe so. I think they just changed their naming scheme for the stepper phases. As far as I have ever seen the connectors always have one phase on one side of the plug and one phase on the other side. So for octopus they called them A phase and B phase and on the max ez they named them phase 1 and phase 2. If the wiring was changed that would mean one phase was the center two pins of the plug and the other phase was the outer pair of pins. That would mean the Octo max ez would not match the wiring of any other printer board. BTT didn't provide any special wiring diagram and I didn't wire mine in any special way.

I would suggest providing a video or at least pictures of what the problem is that you are experiencing.

It really sounds like you have the A and B stepper motors swapped. If the x axis homes correctly but the y axis moves in the wrong direction the steppers are swapped. If you invert ! both dir pins and the x axis moves in the wrong direction and y axis moves inthe correct direction that also means the steppers are swapped. That's why you can't just invert both direction pins to solve it, and Inverting ! only one of the dir pins will just swap X axis movement to Y axis movement and vice versa.

I would try using the stepper buzz commands to identify which motor is turning and what direction

https://docs.vorondesign.com/build/startup/

For Voron 2.4 and Trident:

Both motors clockwise moves carriage to the right as seen from the front of the machine

Both motors anticlockwise moves carriage to left as seen from front 

A motor clockwise, B motor anticlockwise moves carriage towards front away from motors

A motor anticlockwise, B motor clockwise moves carriage rearwards towards motors

Hello,
Swapping the PIN didn't solve the problem.
Now I've made a few exceptions when testing the axes with the command "STEPPER_BUZZ STEPPER=stepper_x". According to the manual, the motors should rotate to the left. The A motor (X) works correctly and the B motor goes wrong in the video, but I corrected it, I just didn't want to make a new video. . Then, as you can see in the video, I tested first with X and then with Y. As you can see, a lot of things are already going wrong with the X movement. Either it should go to the left (X axis), which it does, but the Y axis is moving incorrectly. As you can see in the last video, the axes are moving completely wrong......  . Unfortunately, videos are too large or is there a way to send

[Penatr8tor]

On 3/9/2025 at 12:23 AM, McCosch said:

Swapping the PIN didn't solve the problem.

It can be very confusing. Just wait until you build a VzBot AWD where you have 4 motors to configure, A1-A2 and B1-B2. 

On 3/8/2025 at 5:45 PM, Methos said:

There are two phases to fixing a CoreXY: swapping the stepper connections IE X to Y or Y to X and then you adjust the direction pins.

@Methos is on the right track. I will try to explain.

Each of the two motors has 2 wire pairs equaling 4 wires. from left to right on the connector the color sequence from pin 1 (square pin) should be black, green, red, blue. As far as the confusing pin labeling 2B-2A-1A-1B on one board and A1-A2-B1-B2 on another... It appears there is no labeling standard so, it seems everybody just makes up their own standard without letting anyone know. 

On 3/8/2025 at 11:40 AM, McCosch said:

As you can see in the pictures, the order of the PINs is different.

On the upper board 2B-2A is one pair and 1A-1B is the other pair. The two pairs are 1 & 2 with the leads being A & B while on the lower board the pairs are A & B and the leads are 1 & 2. All of this sounds confusing at first but...

Just know this... The motor wires are in pairs black & green is one pair and red & blue is the other pair.  And if you wire the connector black, green, red, blue... it will work 99% of the time, there's always the 1% that's different from everyone.

It's also important to note that the wire pairs can be flipped, red, blue, black, green and the motor will still work, albeit in reverse but, for solving this problem... make sure that your motor cables follow the black, green, red, blue wiring scheme. I've wired 5-6 different controller boards and all of them work with the motors wired black, green, red, blue and they all probably have a different 1A2B-1B2B kind of wire labeling.

Next thing is to make sure you have the correct motor connected to the correct connector on the board.

Below is the "A" (X) Motor

 

Below is the "B" (Y) Motor

 

Do yourself a favor and mark the top of the motor pulley with a dot or a line using a sharpie pen aka permanent marker. This will come in super handy when you test with STEPPER_BUZZ and FWIW... the motors should rotate clockwise (from left to right). Obviously use ! to invert if they don't both rotate clockwise when tested.

Lastly...

Try connecting your motors to 3 & 4 and try the code @SirDangalf posted.

If you've got the motors wired correctly and connected to the right ports... everything should run smoothly.

 

[SirDangalf]

Hi McCosch

I've a question. Is the printer.cfg of your zip-file the printer.cfg you are using?

If so, then it's clear what's your problem is.

In this printer.cfg you set kinematics to cartesian! Vorons are kinematics corexy!

[Penatr8tor]

58 minutes ago, SirDangalf said:

In this printer.cfg you set kinematics to cartesian! Vorons are kinematics corexy!

Good find!

That could make for some strange motion.

[McCosch]

5 hours ago, Penatr8tor said:

Good find!

That could make for some strange motion.

Hello, Unfortunately I cannot follow your thoughts on what you mean by "kinematics to cartesian". This is the first time I have heard or read about it. But it could also be because of the translation that it seems incomprehensible. Could you explain the difference to me in the Printer.cfg.

[SirDangalf]

In line 16 of your printer.cfg you've set:

kinematics: cartesian

but for a voron 2.4 there must be set:

kinematics: corexy

The setting is needed to tell klipper how to control the steppers.

Edited March 10 by SirDangalf

[McCosch]

6 hours ago, SirDangalf said:

In line 16 of your printer.cfg you've set:

kinematics: cartesian

but for a voron 2.4 there must be set:

kinematics: corexy

The setting is needed to tell klipper how to control the steppers.

 

Thank you very much for this information. I will correct it and test it. I checked where the entry "kinematics: cartesian" comes from, it comes from the original printer.cfg from BIGTREETECH Octopus Max EZ. That's why I didn't notice it.

Thank you very much. When I'm back home I'll test it straight away.

 

[McCosch]

 

Hello, I got home today and have to make the correction in the printer.cfg file right away, and it's working.

Now I'm in the process of setting up the QGL, but unfortunately the printer head moves too far to the left and then stops. Maybe you have an idea? I'd be very happy to hear it.

 

[McCosch]

[mvdveer]

Left front is 0,0 so if it moves to far to the left it may have to do do with your definitions of your X-Endstop as X=50 should be well off the edge of the build plate. Do you get any error messages when this happens?

[Crashdown]

Your problems are stemming from using the default Max EZ config. You really should start with a voron config and change the pin names to match the Max EZ.

For instance:

# Motor-1
##  B Stepper - Left
##  Connected to MOTOR_1
##  Endstop connected to DIAG_0
[stepper_x]
step_pin: PC13
dir_pin: !PC14
enable_pin: !PE6
rotation_distance: 40
microsteps: 32
full_steps_per_rotation:200  #set to 400 for 0.9 degree stepper
endstop_pin: !PF0
position_min: 0
position_endstop: 0
position_max:200     
homing_speed: 50
 

Have you changed poistion_endstop and position_max to 350 for the B and A motor

In the BTT octopus github they have a voron 2.4 config available so you can compare it line by line with yours.

https://github.com/bigtreetech/BIGTREETECH-OCTOPUS-V1.0/blob/master/Octopus works on Voron v2.4/Firmware/Klipper/BTT_OctoPus_Voron2_Config.cfg

The config you posted also has two bed_mesh sections defined

Edited March 15 by Crashdown

[McCosch]

6 hours ago, mvdveer said:

Die linke Vorderseite ist 0,0, wenn sie also zu weit nach links verschoben wird, kann es mit Ihren Definitionen Ihres X-Endstops zu tun haben, da X=50 weit vom Rand der Bauplatte entfernt sein sollte. Erhalten Sie in diesem Fall Fehlermeldungen?

Now I've set up the test run (QGL) for X;Y and I was able to configure the temperatures. Now I just need to set the pressure head. My mistake was in the QGL setting.

[McCosch]

Another mistake was the distance traveled from x;y.
They traveled 200mm instead of 100mm, which is why they kept colliding with the edge.