How can I change the Z axis length to 320mm in firmware?
Hi,
I have just finished building an original prusa mk3s on a 320 Bear frame. The only change is the frame - everything else is MK3s.
My goal is to be able to follow on the updates of the original Mk3s while having this taller and more rigid frame. What do I have to do to the firmware to pass the XYZ calibration?
RE: How can I change the Z axis length to 320mm in firmware?
No one?
RE: How can I change the Z axis length to 320mm in firmware?
Looks like you can temporarily use a bear firmware to pass xyz calibration. Or an older prusa firmware.
RE: How can I change the Z axis length to 320mm in firmware?
Thank you both for taking the time to look into this. I have replaced the smooth rods only, to pass the calibration only - and it worked. I have of course tried the Bear calibration firmware, but this one, too , expects the 220mm Z axis length, so not a solution unfortunately. I thought the Bear calibration firmware was for unlimited Z length, but nowhere near. Then, I looked into the Zaribo firmware, on their website (Zaribo), which they have 3 versions for each Z axis version they do (220/ 320/ 420). But, apparently the motor direction is opposite; something I can fix easily within the Arduino IDE, but I haven't tried this one yet. For now, it's working just fine, running the latest prusa firmeare 3.9.3, but limited to 220 mm of Z axis length.
I wanted to just modify the Z_MAX somehow in the formware, but it is not easy. It is in multiple places for the calibration and not only.
RE: How can I change the Z axis length to 320mm in firmware?
If you haven't already, download Arduino IDE 1.8.13 www.arduino.cc/en/software, then get the latest Prusa Mk3 firmware over at github.com/prusa3d/Prusa-Firmware, Open this file in IDE, edit Zmax to suite your machine now Z=320mm, recompile firmware, flash to printer. Unless you have previous experience with Arduino and/or code, it's a fairly in-depth and multi-step task, but you can do it.
RE: How can I change the Z axis length to 320mm in firmware?
. But, apparently the motor direction is opposite; something I can fix easily within the Arduino IDE
Or use Zaribo firmware and just swap your wiring to stepper coils for opposite rotation:
Motor moving the wrong direction
To get the motor moving in the right direction, is actually does matter which coil is which and what the polarity of the coils are. However, if they're wrong, the motor just turns the wrong way, it's easy to fix that by swapping wires. Pick one of the following in order to reverse the stepper's direction:
- Switching the polarity of either (one) coil, like changing ABCD to BACD or ABCD to ABDC.
- Swapping the coils, like changing ABCD to CDAB.
- Stepper direction can also be reversed in the firmware.
- Plugging the plug in backwards (in case your electronics' plugs allow that). This swaps the coils, and reverses both coil A and coil B. Thus the effect is to change the direction 3 times, which gives a net effect the same as changing the direction once. Only few electronics allow that, because you have to figure the right way not once, but each time you connect the stepper.
RE: How can I change the Z axis length to 320mm in firmware?
Pretty sure I've misunderstood what yo want but the literal answer is to amend the variable Z_MAX_POS in Configuration.h
RE: How can I change the Z axis length to 320mm in firmware?
Thank you for the info. I have changed my plans and I will revert the Z axis length to 220mm or whatever the original prusa is, for several reasons. I want this printer to fit inside the LACK enclosure and I'm going to add the mmu2s to it, so I want to able to use the firmware I need with ease, and not have to mess with it everytime before I install it. Also, never have I needed to print something taller than 220mm. Being it a 1:1 clone will make things much easier with Marlin and Prusa firmware. I am building another 3 printers with Duet boards. One of them is the Ender 3 ,which will accomodate the longer aluminum extrusions and z motors with screwwleads of this aforementioned modification, and easily enough will become a taller Ender 3 with zaribo Z steppers w/ 320mm screwleads.
If someone wants to have a taller Prusa i3 mk3, then they should look into the Caribou firmware, as well as, the Zaribo firmware, for a ready hex file for 320 and 420 mm verisons. I stopped working towards the taller prusa, so haven't done the editing of the .h files, but from what I read, it is the Z_max_pos length that need to be found and replaced within the code text. Nevertheless, this could change from version to version and I don't want to have to keep up with the next solution and such.
RE: How can I change the Z axis length to 320mm in firmware?
Don't have any prove but I doubt if something as basic as Z_MAX_POS is going to change. From the little I know of Marlin most config version differences are additions.
RE: How can I change the Z axis length to 320mm in firmware?
@towlerg
I think Nick Cent was referring to the process of maintaining the extended Z=320mm with each new firmware release. When Prusa releases a new version, will have pull it from GitHub(which will be Prusa Z default, so upon flashing to Mk3 overwrite 320mm back to 210mm), open file in ArduinoIDE, edit Zmax from standard 210mm to 320mm, recompile, just to be able to flash latest firmware. Compared to Prusa's updating firmware very easy .
From doing this twice myself, unless you have a very good reason to extend an axis(making $ for business etc) it's not worth it. I converted an Mk3s to what I call my PrusaTall 1000mm on the Zaxis and kept standard 250mmx210 print bed. It's been running on 2yr firmware b/c never have time to recompile to newest firmware, whereas by 5 other Mk3s and Minis are always up to date.
RE: How can I change the Z axis length to 320mm in firmware?
Someone would probably be able to drum up a decent amount of webtraffic if they cobbled together an online compiler that would take X/Y/Z axis maximums in as inputs (maybe some other common settings).
I would super duper appreciate it if someone could compile firmware for an MK3S+ with Z_MAX_POS=200
I installed a new hotend that is a bit longer and need to shorten the Z-axis to avoid failing calibration issues. I am on Windows and it is a nightmare to get this to compile.
Thank you in advance to some good Samaritans out there!
RE:
So, I did this earlier this year. I built a Bear with a 100mm extended Z axis; extending the smooth rods and lead screws by 100 gets you 310mm, not 320mm. The medium height Zaribo is indeed listed as 320 and I am not sure where the extra 10mm comes from... Either they are using smooth rods and lead screws that are 110mm taller than stock Prusa (seems unlikely), or there is some other hardware difference they were able to squeak another 10mm out of. So the standard Zaribo firmware is not likely to work, either.
One other thing I found is that adding 100mm to the height in the firmware is not as simple as just changing the Zmax position value that was mentioned above. I tried that and it generated errors when I tried to compile. Besides the Zmax, there were at least a couple other things I had to change in more than one file in order to get it to compile and function properly. I had a lot of help from members of the Bear Discord in figuring out what all needed to be changed and there was some trial and error involved. The 200mm Zmax position mentioned above probably IS as simple as changing the one variable. Going with the 310mm height was over some limit that caused a floating point related error, which shouldn't be the case going 10mm lower than stock.
My firmware is a slightly modified version of the Bear calibration firmware, which is itself a slightly modified version of the Prusa firmware. The main change in the standard Bear firmware involves the difference in nozzle heights on the extruder, but that's not the only change. The Bear calibration firmware supports hot end cooling fans other than the ones the Prusa factory ships with its printers. As I understand it, Prusa has prioritized quiet operation over cooling, so if you put a different fan than the Noctua or the Delta (which I was told Prusa sometimes has used when the Noctua is not available in the quantities they need), it may live a short life using the standard Prusa firmware. The Bear firmware supports higher output fans.
The Bear firmware is not up to date with the current Prusa firmware, in case that matters to you. I think it's on Greg's to-do list, but he appears to be focused on bringing BearExxa V2 out of beta and into the release version right now. In order to not get a nag message to update my firmware when using the current version of PrusaSlicer, I had to comment out the firmware version check in my start Gcode. It can supposedly be disabled through the printer control panel but when I made that change, it didn't stop the nag message.
RE: How can I change the Z axis length to 320mm in firmware?
If anyone is still wondering how to change the z height in firmware and compile it in windows, I just did it to accommodate a phaetus rapido hotend. The file that you need to change is:
Firmware/variants/1_75mm_MK3S-EINSy10a-E3Dv6full.h
This is for my MK3S.
Change value on this line:
#define Z_MAX_POS 210
I installed Ubuntu for windows and followed the compiling guide on github：
https://github.com/prusa3d/Prusa-Firmware#using-linux-subsystem-under-windows-10-64-bit
RE: How can I change the Z axis length to 320mm in firmware?
I was finally able to get the firmware to compile - trick was not to use the latest version but I cannot recall what version someone recommend I use. The latest version just had all sorts of random bugs in it. Once I downloaded a different version it compiled fine with my modifications to the Z-axis height.
RE:
If anyone is still wondering how to change the z height in firmware and compile it in windows, I just did it to accommodate a phaetus rapido hotend. The file that you need to change is:
Firmware/variants/1_75mm_MK3S-EINSy10a-E3Dv6full.h
This is for my MK3S.
Change value on this line:
#define Z_MAX_POS 210
I installed Ubuntu for windows and followed the compiling guide on github：
https://github.com/prusa3d/Prusa-Firmware#using-linux-subsystem-under-windows-10-64-bit
Glad you got it working. As I mentioned above, if you are going to a shorter Z Max (such as to use your longer Rapido hotend); it is indeed as simple as you describe. If you are trying to go taller, not so much. I eventually got my firmware to compile with much help from people who understand it better than me. If a person wanted to build a 100mm taller Bear using the Bear Exxa X-axis and extruder, and doesn't mine being stuck on firmware version 3.10, then I could probably hook them up.
Realistically I think that going forward, my upgrade path for the tall Bear that I built is going to eventually include switching it over to Klipper, or possibly RRF on Duet. I am already running Octoprint on a Pi 4B, so I have the hardware end of that covered. I have been told that Klipper will work fine with the Einsy board, but it's best to upgrade the bootloader first because the Prusa one is buggy.
RE: How can I change the Z axis length to 320mm in firmware?
@ Netpackrat
I recently purchased a mk3s bear exxa with bear extended z frame assuming it came with preinstalled firmware but that was not the case. I have been determined to get it function in it current form. After messing around with VS Code and Arduino IDE I realized its not as simple as just changing z_max_pos. I am super novice when it comes to code but am learning. I would love to try the firmware you compiled. Better yet, do you have the modified source code you compiled from by chance? The modified source code would be really great bc i could compare it to the Bear exxa source code and learn what modifications to the code needed to be made to accommodate a higher z axis. Any help would be appreciated.
RE: How can I change the Z axis length to 320mm in firmware?
Just a quick note to acknowledge that I read your reply. Been super busy between work, trying to keep up with snow removal around the house, and building a Voron 2.4. I didn't take very good notes last year while working on the firmware since I was mostly focused on just getting it working. Most of that stuff is on the computer I use for CAD and I have literally not done anything with the firmware files since I got the printer working.
If your Bear is the same dimensions as mine then I think my compiled firmware should work. Bear Exxa with 310mm Z axis. Will look into zipping it and maybe posting as an attachment here.