so, i was trying to calibrate my stepper drivers (a4988) because for the last week or so, they’ve been making a horrible noise, and i haven’t had the chance to calibrate them since i built this kit.
the board is called Mpx.3 by the manufacturer (max micron) and they claim it’s an mks-base derivative (i can take pictures later when i’m home), which is basically a ramps 1.4 with a4988 drivers and another fan/bed FET onboard. i’ve flashed it with the latest marlin rc, with the configuration matched ofcourse.
i started out with the x axis, and turned the pot (counter clockwise) until movement stopped, i then started turning the pot clockwise and expected the stepper to start moving, but instead i get a “mintemp” error.
i checked and bed temp control and monitoring is fine and both extruders are as well, so it’s not a thermistor or connection problem.
i tried playing with the pot some more, but nothing helps - trying to set a travel to max x results in nothing happening, and setting a travel for min x immediately results in the “mintemp” error and the firmware immediately halts.
anybody have any ideas i could try or if this is even fixable?
or is the board/driver completely kaput?
do you mean where the tip is made of plastic or the body is insulated? mine has a plastic grip and a magneric replaceable tip, i’ve never seen/heard of one with a plastic tip, though it might make sense for sensitive electronics.
do you think the tip.might have shorted something out?
there was no “magic smoke” coming out, and as far as i can tell everything else works just as it should.
i also forgot to mention before, to make sure the pot wasn’t damaged i measured and it showed 4.71kohm, the other 4 were showing close values ranging from 4.67kohm to 4.92kohm.
I couldn’t see you having an issue with anything but the trace or thermistor. But yes you should be using a plastic Phillips screwdriver to adjust it. Mine have had issues otherwise
it doesn’t look like 2 separate issues, as it does not happen when heating the hotends or the bed, nor does it happen when moving any of the y and z axes.
this only happens when moving the x axis towards the minstop and does not happen when trying to move the x axis away from the minstop (instead nothing happens).
as i.mentioned, first thing i did was to check thermistors and connections but i’ve tested lowering and raising hotend temps and bed temps a few times and it works just as before. and it’s definitely not a loose wire moving becuase i can’t get the x axis to even move
i’ve checked all the soldering and connections with a magnifying glass under a bright light and everythong seemed fine, i can take another look when i’m home but i don’t nelieve that’s it either, or there would have been symptoms by now…
It sounds like a pin or MCU issue. The current Marlin RC isn’t production ready, check the pin out definitions and make sure the pins file is correct. I’ve had similar issues with low cost boards where the MCU was bad or the solder pads weren’t fully flowed or had flash between them.
guys, i really appreciate your ideas - but i must not have made it clear that this is a working printer, i’m not setting it up for the first time.
i’ve had it working for about 5 months now, been on the latest RC for about 2 weeks now. all of the RC’s have performed pretty solid for me, much better than the v1.0 variant that came with the board.
it’s not pinout settings (because those were not changed since rc3 or 4 i think when they moved to the new separate pins files).
just the same it also could not be the x endstop, but to make sure i triple checked by also changing to the y endstop which works fine, and totally disconnecting any endstop (changed the config for that to work).
the manufacturer did provide the old marlin v1.0 based configuration (actually the whole thing which i diffed against the original git to see the changes), but it’s basically just a ramps 1.4 efb (actually an eefb - because double extruders) on a single board.
my wife just complained that the printer has gotten louder, and i noticed i hadn’t calibrated the drivers since i got it, because the manufacturer said it comes dialed in, and it was pretty silent this whole time.
this is where my first post comes in…
i think @Griffin_Paquette may be right and the screwdriver could have shorted something out… i’ve never heard of plastic ones, and i went to the hardware store where they said they’d never heard of one as well.
i think that in the meanwhile i can just change the pin used for the driver of the 2nd extruder to be used as the x axis until i figure this out and maybe print something to be used as a screwdriver for the pot.
I can’t remember if it was ceramic or plastic but my friends I3 kit came with one to tune the drivers. I always did it one at a time and unplugged my power supply when I adjusted each one.
i just cut a toothpick in 2 and filed it a bit, works like a charm, will test the other steppers tomorrow, i’m just wandering what kind of damage was done when/if the screwdriver shorted…
will probably have to source a new board if i can’t fix this one…
yeah, i’m just trying to figure out if i should get a ramps with a mega, or get a due and try and get my hands on a radds or go the smoothie way. i remember there was an article published about a month ago where someone compared them, but i don’t remember the outcome…
i’m pretty sure that unless i get a radds, i’ll probably have to mod the board, because with dual extruders, a heated bed and 2 fans i don’t think a standard ramps or smoothie have more than 2 or 3 FET’s.
has there been any good (yet cheap-ish) board choice discussion that i missed lately?
@Tom_Keidar There have been enough changes between RC3,4 and 5 to break existing configs including some pin configs. I’ve had issues with changes with Mini Rambo on every rev so much so I’ve done a fork that that I’ll use specific to my next machine configs. Unless you’ve checked the code don’t assume nothing has changed. These are not release candidates in the way that software engineering defines a release candidate. They are general beta releases and in some cases the features or structure are first time releases. For example abstracting the pin defs to separate files.
If you shorted the stepper driver (I’ve tuned hundreds of drivers, literally, with a small metal jewelers screw driver) that may have lead to a damaged MCU. A min temp if not triggered by a failed thermistor, firmware bug/error or connection failure would likely be failure of the MCU.
as mentioned, my board uses the ramps 1.4 configs and those have basically had no changes over the rc’s, they were just separated into different files with some “#defines” so it’s easier to make “custom” header files for supporting different boards.
being a software, realtime, and kernel developer i’ve monitored those changes closely and i can assure you this has nothing to do with the changes.
also, there’s the whole “been running it for about 2 weeks now with no problems” and the whole thing started while i was calibrating motors, and now only happens when that specific (the one i tried to tune) driver is operated in a specific direction (the one i was tuning on), so i believe it may have been shorted and damaged, it’s just something that i’m surprised no one mentions in any tuning guide/video/blog post.
this is not the first time i’ve tuned a stepper driver (robotics, cnc, and other 3d printers), so i’m kinda surprised by this…
is this a common thing? is this so known a problem that no one bothers even mentioning it?
