You definitely want Z_SAFE_HOMING to be enabled if you are using your Z-probe as your endstop.by MMcLure - Printing
Many printers will not move the extruder motor unless the hot end is at Printing temperature. Try preheating the hot end and see if that makes a difference.by MMcLure - General
Once you've figured out the right Z offset, make sure you set it as your new Z_PROBE_OFFSET_FROM_EXTRUDER (and do the M502/M500/M501 dance) so you don't need to worry about it again.by MMcLure - Firmware - Marlin
Your configuration looks OK, except that Z_PROBE_OFFSET_FROM_EXTRUDER is 0 - that means that the printer thinks that Z=0 is wherever the z-probe triggers when homing. So out of the box (no M851 command) you would expect the nozzle to be a distance above the bed. Try the following commands: M851 Z0 G28 M211 S0 This will home the printer and disable software endstops so you can move the head downby MMcLure - Firmware - Marlin
The guy who designed the MGN12 linear rail upgrade for the A8/AM8 recommends these: CNA Store, although I don't have any personal experience with them.by MMcLure - General
The settings that configures that are Z_CLEARANCE_BETWEEN_PROBES and Z_CLEARANCE_MULTI_PROBE (if you have MULTIPLE_PROBING enabled). Those look fine in your configuration, but as obewan suggests it seems very strange that with a capacitive probe you have a positive Z_PROBE_OFFSET_FROM_EXTRUDER - that is usually only the case if you are using something like a piezo sensor that uses the nozzle tipby MMcLure - Firmware - Marlin
MAX_TEMP is defined primarily for safety - i.e. "if the printer goes over this temperature stop the print/shut down the printer/etc." It is defined as a temperature that you would not expect to reach in normal operation, even if your PIDs aren't quite up to snuff and the temperature oscillates somewhat around the set point. That's why there's the 15C difference between the temperature that is allby MMcLure - Firmware - Marlin
In any case if you change anything in your heating system (thermistor or heating cartridge) it is probably a good idea to redo your PID tuning.by MMcLure - Printing
Quotedc42 I suggest you ask Panacutt. But it would be surprising if a connector marked PS_ON wasn't 5V tolerant. Yeah - it's probably OK. But I decided that for the price of two resistors and a 2N3904 it wasn't worth the risk so I built up a little switching circuit.by MMcLure - Controllers
I'm trying to figure out if it's safe to connect my power supply directly to the PS_ON pin on a Re-Arm/RAMPS 1.4 combo. The "enable power" pin on my DPS-600PB power supply is 5V that needs to be shunted to ground to turn the PS on. This works great on my Mega2560/RAMPS combination, but I'm concerned about the Re-Arm's ability to switch the 5V signal from the power supply. Input pins are supposedby MMcLure - Controllers
Essentially it depends on the move. If you're moving in just one dimension then the printer can theoretically achieve the maximum jerk/acceleration/speed on that axis. But when it's moving in more than one dimension at once (and yes, the extruder counts as a dimension) it has to figure out which is the most limiting of those settings. So suppose your X axis can move at 100mm/sec but your Y can onby MMcLure - Firmware - Marlin
I measured a 1N5819 at a reverse leakage current of 61uA at 12.5V. Is that really enough of a leakage to be concerned about in this application? I'm wondering because I'm planning to upgrade to a 3.3V board myself.by MMcLure - Controllers
I don't think you can use different settings for the bed and hotend.by MMcLure - Firmware - Marlin
Just find a board that's listed with a green heart in the first post of https://github.com/MarlinFirmware/Marlin/issues/7076 and have at it. The current state of the bugfix-2.0.x branch is very usable, both with 8 and 32 bit boards. I've been using it on my RAMPS/Mega2560 combination with no issues at all.by MMcLure - Firmware - Marlin
By default on an AVR such as RAMPS with Arduino Mega the heatbed/hotend PWM frequency is the 7.6294 Hz from the table above. You can easily see the heatbed and hotend MOSFET LEDs flashing at that rate. This makes sense since SOFT_PWM_SCALE defaults to 0.by MMcLure - Firmware - Marlin
In a related question, would using an 0.9 degree motor with 8 micro steps be more precise than a 1.8 degree motor with 16 micro steps?by MMcLure - General
If you have enough flash available on your board you can try enabling G26_MESH_VALIDATION - this will allow you to print a test pattern that you can use to tweak the mesh points before saving the mesh.by MMcLure - Printing
I personally would recommend using a 12V COB. That's what I have set up on my "Anet AM8 of Theseus". I have enabled RGBW LEDs in Marlin, and have an RGB strip attached to the frame and a pair of COB LEDs (described as "4W" although the wattage is very dependent on the input voltage) on an adjustable arm. I use pins D4, D5, D6 and D11 from the "Servos" connector to switch these on and off throughby MMcLure - RAMPS Electronics
Ah, yes, the Benchy "waterline". I also saw this exact problem when I switched from Cura to Slic3r Prusa Edition. In my case it was due to insufficient running of the cooling fan. I had the default fan settings, and right at the level of the "waterline" is where the solid deck starts printing. This caused Slic3r to completely disable the fan for those layers because the time per layer was very loby MMcLure - Slic3r
I would see this regularly if I tried to use an 0.3mm initial layer height. I switched to using 0.2mm initial layer height and that solved the problem for me.by MMcLure - Slic3r
If there are any heating commands in the custom start gcode Slic3r won't put them in by itself. So you can do something like M109 S ; heat up nozzle G12 ; clean nozzle in your startup code so you can get the behavior you want. I use this on my printer so the bed heats up before I home (I use an inductive sensor in the middle of the bed so I want the bed to do any warping before probing). The rby MMcLure - Slic3r
Quoteunf0rg0tt3n Thanks for the tip about the 1N5817! What microcontroller pin do you mean, because by "ENDSTOP_PULLUP_Z_MIN" I think you mean the endstop Z_min? I't still on I have my mechanical end stop still connected. Ah - I assumed that if you were using a probe you were also homing with the probe. Change Z_MIN to whatever endstop pin you are using for the probe. Do make sure you're usinby MMcLure - Controllers
Another possibility is to just use a reverse-biased schottky diode like a 1N5817 instead of a divider network. Connect the cathode (striped end) of the diode to the signal wire from the sensor, and the other end of the diode to the microcontroller pin, and turn ENDSTOP_PULLUP_Z_MIN on. When the sensor is not sensing anything, the diode will block the voltage and the pullup will pull the signal piby MMcLure - Controllers
Check and make sure that the tabs on the MOSFETs on the RAMPS board aren't touching. That can cause weird behavior with the heaters.by MMcLure - RAMPS Electronics
QuoteMikor Thanks, but the z homing direction was already set at "-1". Should I set it to "1" and flip the plugs? That would be correct. Also, instead of reversing the plug you can change INVERT_Z_DIR in Configuration.h (assuming you're running Marlin).by MMcLure - RAMPS Electronics
Instead of an ATX power supply, let me recommend an HP DPS-600PB server power supply. This is a 47A 12V power supply that can be bought for around $20 shipped on eBay, doesn't require a dummy load to give full power, can be switched on/off with a single wire like an ATX supply, can be easily modified to allow two in series for 24V, and is pretty much bulletproof. The only thing I don't like aboutby MMcLure - General
Try the fix described in https://github.com/MarlinFirmware/Marlin/issues/11788.by MMcLure - Firmware - Marlin
If you're using a printer host (like Repetier Host, Pronterface or even Octoprint) you can print out the current mesh with "G29 T". Any points that were not probed will show as ".". Then the recommended procedure is to run "G29 P3" so UBL can interpolate/extrapolate the missing values. It might take more than one run of "G29 P3" to fill in all the unprobed points. Then print out a mesh validationby MMcLure - Firmware - Marlin
Use the original U8glib, not U8G2. The code in Marlin expects the older library. At some point it may be updated to use the new library but that point has not been reached yet.by MMcLure - Firmware - Marlin
What sort of sensor are you using? If it's an inductive or capacitive sensor you want to keep away frrom probing the very edges of the bed - these probes tend to have trouble at those locations. Marlin 1.1.9 includes a MIN_PROBE_EDGE setting that ensures that only points a certain distance away from the bed edges are probed. If MESH_INSET is less than MIN_PROBE_EDGE, this means that some of the pby MMcLure - Firmware - Marlin