Problem after problem, getting very frustrated- please help
I'll make it short and sweet-
The filament motor gets way too hot, causing the filament to jam and bubble between the gears- I've tried pulling out the sensor but that doesn't appear to work-
I'm new to this, but everybody seems to love this thing- I have not had 1 successful print since I've received the MK3, please help...
PS: on top of the motor heat, bed adhesion is also a big problem, I feel like i need to babysit the darn thing every minute or something happens.
Re: Problem after problem, getting very frustrated- please help
That sounds like a very serious problem. It should not be melting filament at the gears. I would contact support and see about some replacement parts.
Re: Problem after problem, getting very frustrated- please help
Support does not help, and I've read other people having this issue, with all the issues it CAN'T be me.
if somebody has had this issue and has fixed it, please let me know, I'm getting ready to just want a refund.
PS: person with the same issue-
Re: Problem after problem, getting very frustrated- please help
The Problem with generalizing Problems like that is that not everybody is having them. So most likely its due to: bad parts / individial setup / differences at assembly and so forth.
I dont have the problem but here is what you can try:
put some grease on yor gears. It reduces friction and heat quite alot. (grease not oil)
Lower the tension on your idler screws. you are looking for the minimal tension it needs to grip the filament. anything above just increases friction between the gears.
You can also try to put some heatsinks on the extruder motor. i did just in case and it cant realy hurt.
i do have serious trouble with parts not sticking and having to adjust my live Z at every single print. Especially when going to a different temperature. I dont have another printer so i just put it down to "3d Printing trouble" and cant realy say whether or not i just suck at cleaning my bed or if something is up with my printer... 😉
Re: Problem after problem, getting very frustrated- please help
1. Try to reduce the extruder idler tension. By trying to block the filament manually while extruding, you get a feeling of how much tension is needed to have enough grip on the filament for being still pulled in reliably.
2. Add the following G-code commands to your start script:
M911 E31
M912 E31
Regarding the second point, please take the following explanation with a grain of salt, because I have not yet dug too deep into the innards of the motor driver and how it is handled by the firmware. As far as I can see, the axes are configured differently regarding what features of the motor driver are used. Z and E seem to be the same in that they use just a simple mode (e.g., no silent mode). This makes the definition of all the currents and thresholds and whatever easier for these two axes. However, the definition of the motor currents in the firmware is really weird and counter-intuitive. Currently, the value for the E-motor is 36, which is higher than for Z (28), but apparently not by too much. But because of the weird encoding, 36 is interpreted (still at the firmware level) as something like 32+36/2=50 ("something like", because values above 31 are realized differently by the hardware). So if one wants to get something like 36, one would actually need to use the value 64+2*(36-32)=72 (the "+64" is just good for getting a value above 31 and will be masked). As I said, it is counter-intuitive. I use the value 31, which seems to work well (so the motor is still strong enough), even though it still gets relatively hot, but still cool enough so I can touch it and hold the touch.
Regarding the two commands, M911 defines the "hold current", M912 defines the "running current". The values have to be either both above 31 or both below (or equal) 31. I actually have set all my hold currents to "6", but I don't know how much this actually helps to keep the motors even cooler. In the firmware config, the same values are used for "hold" and "running" anyway. BTW, the command M913 reports the currently used values.
Re: Problem after problem, getting very frustrated- please help
Could it be that your Z level is too small, so that the extruder motor must work very hard to push the filament out?
Some first layer image samples can provide a good explanation.
Bear MK3 with Bondtech extruder
Re: Problem after problem, getting very frustrated- please help
Just throwing this out there because I was recently having an extruder problem that took me over a week to figure out...
Tried replacing the PTFE tube , tried replacing the stepper motor, tried replacing the driver, tried different PLA.... same issue.
Turned out that I had dirt in the nozzle....
It wasn't completely jammed up but it caused the extrusion to vary wildly and when retractions happened I would get little pieces of melted bubbled plastic jammed in the extrusion gear which sorta sounds similar to what you are describing.
Try swapping out your nozzle and see if there is any change.
Regards!
Re: Problem after problem, getting very frustrated- please help
Thanks you guys- will report back
Regarding the Oil- what type of oil is best to use?
Re: Problem after problem, getting very frustrated- please help
PTFE grease or white lithium grease on the gears only. Try not to get any near the Filament path. Oil is difficult because it gets on the filament path.
Cheers
Oliver
Re: Problem after problem, getting very frustrated- please help
2. Add the following G-code commands to your start script:
M911 E31
M912 E31
Regarding the second point, please take the following explanation with a grain of salt, because I have not yet dug too deep into the innards of the motor driver and how it is handled by the firmware. As far as I can see, the axes are configured differently regarding what features of the motor driver are used. Z and E seem to be the same in that they use just a simple mode (e.g., no silent mode). This makes the definition of all the currents and thresholds and whatever easier for these two axes. However, the definition of the motor currents in the firmware is really weird and counter-intuitive. Currently, the value for the E-motor is 36, which is higher than for Z (28), but apparently not by too much. But because of the weird encoding, 36 is interpreted (still at the firmware level) as something like 32+36/2=50 ("something like", because values above 31 are realized differently by the hardware). So if one wants to get something like 36, one would actually need to use the value 64+2*(36-32)=72 (the "+64" is just good for getting a value above 31 and will be masked). As I said, it is counter-intuitive. I use the value 31, which seems to work well (so the motor is still strong enough), even though it still gets relatively hot, but still cool enough so I can touch it and hold the touch.
Regarding the two commands, M911 defines the "hold current", M912 defines the "running current". The values have to be either both above 31 or both below (or equal) 31. I actually have set all my hold currents to "6", but I don't know how much this actually helps to keep the motors even cooler. In the firmware config, the same values are used for "hold" and "running" anyway. BTW, the command M913 reports the currently used values.
Outch! Scrub this as it is pretty much all wrong. I misinterpreted the TMC2130 datasheet.
Re: Problem after problem, getting very frustrated- please help
Just a +1 on this, another one with the same problem - filament getting too hot to handle, and I have a feeling it's getting worse... From the beginning everything works, now I'm unable to use PLA due to melting it before it goes into the extruder. Not good Prusa! Do something please!