Frequently Asked Questions
The
mpmd_marlin_1.1.xfirmware is NOT designed for the V2 model of the Monoprice Mini Delta 3D printer. Monoprice recently began selling a V2 model of the printer, and I doubt that this firmware is compatible. Please, do NOT try to install this firmware on the Monoprice Mini Delta V2 printer.
- Why am I getting a Thermal Runaway Protection error with the
-05Alimitfirmware? - Settings are INCORRECT for older printers with 1/8 micro-stepping. How can I make it work?
- Why does the
G29command abort and report "Error:Probing failed"? - Why does the printer go "haywire" during auto-calibration?
- I am having trouble connecting over USB on Windows 10. How can I fix this?
- I flashed the firmware and ran the auto calibration, but now nothing I slice prints correctly. What went wrong?
Yes, the "thermal runaway" results from a limitation of the -05Alimit variant of the firmware.
Since the firmware gives priority to heating the nozzle (hotend), it does not maintain the bed temperature while it heats the nozzle (e.g if the nozzle PID control loop demands 80% of the power, the bed will receive a maximum of 20% of the power regardless what its PID control dictates). If Marlin cannot control the temperature (in this case the bed temperature) within a certain time period, it faults signalling the "thermal runaway" condition. Heating the nozzle first can avoid the situation where there is insufficient (remaining) power to heat the bed.
More discussion in issue #1.
@cscott points out in issue #4 that the firmware's default settings are not suitable for printers that use 1/8 micro-stepping motors -- but there is a fix.
In order to use mpmd_marlin_1.1.x firmware with these printers, a few of the settings need to be adjusted BEFORE performing the auto-calibration steps on the printer. As of release 119r09, the contents of the micro SD card include the command, M92_XYZ57_E48.gcode, to assist. Using the /gcode_setup commands on micro SD card, the initial calibration becomes:
M502_FACTORY.gcode
M92_XYZ57_E48.gcode
AUTO_CALIBRATE.gcode
M500_SAVE.gcode
More information can be found in the wiki, Calibrating the Printer.
The specs for the printer claim a build radius of 55mm, but on some printers it doesn't seem to be the case. The nozzle sits a bit high on these printers and allows the carriage to collide with the bed retaining pin. Though it is ugly, it is probably better that the initial setup of the printer detects this situation so the user is aware that the printer is not quite up to spec. There are options for the G29 command to avoid the situation, as well as some other work-arounds that are discussed in issue #11, issue #15, and issue #19.
In issue #4, @cscott reports crashes, erratic motion, and non-sensical output during the printer's auto-calibration process after installing firmware. In essence, the firmware appears to be badly broken. Bizarre or erratic motion is a strong indication that there is a problem with the settings. The M502 (load factory settings) command followed by the M500 (save settings) command should get the firmware operating from a known "ground" state. Using the /gcode_setup commands on micro SD card:
M502_FACTORY.gcode
M500_SAVE.gcode
It appears that Microsoft Windows does NOT recognize the USB serial link created by the mpmd_marlin_1.1.x firmware. Consequently, Pronterface does not identify a COM port that can be used to connect to the printer. This issue is reported by @ramin3 in this issue with follow-up in this issue. Apparently, Windows COM port drivers are needed.
Kudos to
@PurpleHullPeasfor coming up with the solution: install the Windows COM port drivers from Marlin4MPMD (actually from STMicroelectronics).
Information and the drivers can be found at:
This most commonly occurs when someone did not complete ALL of the steps in the Quick Start, as seen here, here, and here. i.e., this usually happens when someone flashes the firmware and runs auto calibration, but does not appropriately update their Start Gcode and/or z-offset. Due to the nature of how some people set configuration values for their printer on stock firmware (especially if you have blindly copy-pasted anything into your Start Gcode in the past), it is recommended to start over at "Step 2: Calibrate the Printer" if you have tried to print a file with your old Start Gcode.
In other words, not everything in mpmd_marlin_1.1.x firmware works exactly like stock firmware. You may have inadvertently set some bad EEPROM settings if you ran stock-style gcode after flashing mpmd_marlin_1.1.x. This is why it is recommended to wipe your machine settings, re-calibrate, print one of the included test models, and then update your Start Gcode, as is covered in the Quick Start.
