Lulzbot Mini thinks its a Mendel printer

This sounds strange, but I recently got a hold of a lulzbot mini. When I connect to it, the console says: “< [XX:XX:XX] Expected that MACHINE_TYPE was LulzBot Mini, but got Mendel instead”. While I was able to simply change my settings to ignore this, I believe it is creating issues as I can not get the z-offset to my printer, as typing M851 (The command to get the z-offset according to this link) into cura’s console gives me no response. I would assume this is because the printer has code for a different type of printer possibly, but I do not know how to tell. I have been able to print with it, however, so that may mean I have different issues.

If it were mine, I’d download the latest version of CuraLE, create a profile for your version of the Mini (if you need help to determine your version, provide the model and/or serial number), and then update the firmware.

If you want to document the current configuration, open the console and enter M115 and M503. Cut and paste the output here using the </> tool above.

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Thank you for your response. I did as follows, and got as follows:

< [13:22:49] Correct response for connection
< [13:22:49] Expected that MACHINE_TYPE was LulzBot Mini, but got Mendel instead
< [13:22:49] Wrong machine detected.
< [13:22:49] Printer connection listen thread started for COM3
< [13:22:49] Established printer connection on port COM3
< [13:22:53] Requesting temperature auto-update
< [13:23:01] Requesting temperature auto-update
> [13:23:02] M115
< [13:23:04] FIRMWARE_NAME:Marlin V1; Sprinter/grbl mashup for gen6 FIRMWARE_URL:https://github.com/ErikZalm/Marlin/ PROTOCOL_VERSION:1.0 MACHINE_TYPE:Mendel EXTRUDER_COUNT:1 UUID:00000000-0000-0000-0000-000000000000
< [13:23:10] Requesting temperature auto-update
> [13:23:12] M503
< [13:23:14] echo:Steps per unit:
< [13:23:14] echo:  M92 X100.50 Y100.50 Z1600.00 E833.00
< [13:23:14] echo:Maximum feedrates (mm/s):
< [13:23:14] echo:  M203 X800.00 Y800.00 Z8.00 E40.00
< [13:23:14] echo:Maximum Acceleration (mm/s2):
< [13:23:14] echo:  M201 X9000 Y9000 Z100 E1000
< [13:23:14] echo:Acceleration: S=acceleration, T=retract acceleration
< [13:23:14] echo:  M204 S2000.00 T3000.00
< [13:23:14] echo:Advanced variables: S=Min feedrate (mm/s), T=Min travel feedrate (mm/s), B=minimum segment time (ms), X=maximum XY jerk (mm/s),  Z=maximum Z jerk (mm/s),  E=maximum E jerk (mm/s)
< [13:23:14] echo:  M205 S0.00 T0.00 B20000 X12.00 Z0.40 E10.00
< [13:23:14] echo:Home offset (mm):
< [13:23:14] echo:  M206 X0.00 Y0.00 Z0.00
< [13:23:14] echo:PID settings:
< [13:23:14] echo:   M301 P28.79 I1.91 D108.51

Looking at the data, it appears as if the machine has the wrong (or at least unstandard) firmware. I would imagine I either need to update my machine type accordingly, or change the firmware of the machine itself. I have an idea on how to do both, but I figure I will wait for a reply to ensure I am on the right track here.

If you want to use the machine as a 3D printer, then you need to update the firmware.

First you need to add the printer in CuraLE. You need to know which model of Mini you have (1 or 2) and which tool head you have. The printer model should be printed on the unit (in the back) along with the serial number.

The tool head choice might be tricky. First, remove the tool head from the printer. Carefully disconnect the wiring, put a towel or something soft over the bed (this prevents dropping the tool head which would damage an unprotected bed), and remove the screw holding the tool head to the frame. Look at the back side of the tool head and with luck, there will be a part number printed on it (with some other information you will need later).

If you want some help identifying the printer and/or the tool head. Post some pictures of both and we’ll see if we can identify them for you.

Once you have added the printer with the proper tool head to CuraLE, select Settings, Printers, Manage Printers…, select the printer (if necessary), and clicking Update Firmware.

The printer itself is a Lulzbot Mini 1, with the product code of KT-PR0035NA-3907
The toolhead, on the other hand, is a different story. The only thing that has letters is the stepper motor, and many of the letters on it are scratched out, so I cannot be sure what it actually reads. However, I do believe it is identical to the tool head featured on the product page for the LulzBot mini. The tool head is dirty and needs cleaning (an issue for another time), but seems to be copper underneath. I did intensive research, and believe the tool head is a older version of this websites tool head, but the website does not list any id number except an SKU number, which I believe is just the stores way of identifying things.




I believe this is the Mini 1 Single Extruder so that is what I’d use in the add printer dialog. Last question would be does the printer have an LCD panel? Check (or uncheck) as appropriate (and let us know).

After adding the printer you can go to manage printers and click Update Firmware.

The M115 output should now be reasonable. Try an G28 XY and if that works, a G28 Z with your hand on the power switch in case it looks like the nozzle is diving into the bed.

Further instructions will depend on the answer to the LCD question. My printer is a TAZ 6 so we may need to get some help from someone who has some Mini 1 experience.

Well, I did all that you recommended (The machine does not have a graphical LCD), and it is working as it should. The printer is responding to commands, and I am preparing to check and update settings as we speak. Thank you for taking time out of your day to help me, and for further instructions, I have an online copy of the machines User manual so I should be able to do things from there. Once again, thank you for your time to help me out with this unorthodox problem, as getting the right firmware is (obviously) a total-game changer for me. Thanks!

Two things you will need to configure, the first is the Z-offset (M851) and the second is the E-steps (M92 Ennn). You can verify that the Z-offset is in the ballpark (M851 without parameters will display current values) by moving the tool head to the center of the bed (G0 Z5, G0 X75 Y75) and then slowly lowering Z while measuring the distance between the nozzle and the bed with something like a business card which is approximately 0.3mm thick). If the Z setting is close to this value then your Z-offset is close enough for fine tuning by printing. You can find instructions for setting E-steps in this forum or online.

I would also do a manual G29 V4 (with your hand on the power switch) to verify that the firmware finds the corner washers and doesn’t press down on them (i.e. there shouldn’t be any noticeable deflection in the bed when the nozzle hits the washer).

BTW, a good reference for gcode command documentation is http://marlinfw.org/meta/gcode/.