MK2.5 without new extruder
I'm interested in getting the removable build plate for the MK2, but I don't trust the MK3 extruder yet. My self built MK2 works much better at lower layer heights than my preassembled MK3 and in general print quality and reliability is better.
So, my question is, can I do a partial update and only replace the heated bed and maybe the PINDA probe?
Re: MK2.5 without new extruder
Maybe, you have to use the Mk2.5 firmware but the steps per mm internally are changed. if you recompile firmware it's probably fine otherwise you could probably use start gcode to set the steps back to the original.
I feel like experimentation is due here to see if the bondtech makes the prints shittier or if it's something else. it could be the firmware for all we know.
Re: MK2.5 without new extruder
This could also be the answer for my question here too :
Same situation :
I only want to upgrade the heatbed and the pinda because I've designed my own extruder with alternative fan shroud and part cooling.
Thomas
Re: MK2.5 without new extruder
I don't have any issue mingling with the firmware a bit. One of the questions I guess is, are the PINDA-Spots arranged in the MK3 layout or is there even a third MK2.5 layout? Maybe somebody with the new heatbed could comment.
Yeah, I guess the jury is still out what the issue is with the MK3 extruder.
For me three issues are all connected...
The effective diameter of the bondtech gears is considerably larger. This is why there is less steps per mm (and they limited min layer height to .07 in slic3r) and prusa want's to play with microstepping torque linearisation and had to increase the extruder motor current. I get clogs in retraction intense models, maybe because the extruder gear get's noticeably hot and softens up filament before entering the hotend. I feel a gear reduction would be the way to go... But I don't wanna be messing too much with my pre-assembled unit yet....
Additionally, in my original extruder, and the replacement extruder body (free of charge, thanks prusa), the filament path is not straight, but bends around the extruder gear without any idler pressure. Not sure this is or should be intentional, certainly increases filament resistance and thus motor requires more motor current...
Anyway, I'll wait a bit and see what Prusa comes up with. But I have absolutely fallen in love with the removable build plate... Sure the quiet printing is amazing too, but for me that's just cosmetics.
Re: MK2.5 without new extruder
I don't have any issue mingling with the firmware a bit. One of the questions I guess is, are the PINDA-Spots arranged in the MK3 layout or is there even a third MK2.5 layout? Maybe somebody with the new heatbed could comment.
Yeah, I guess the jury is still out what the issue is with the MK3 extruder.
For me three issues are all connected...
The effective diameter of the bondtech gears is considerably larger. This is why there is less steps per mm (and they limited min layer height to .07 in slic3r) and prusa want's to play with microstepping torque linearisation and had to increase the extruder motor current. I get clogs in retraction intense models, maybe because the extruder gear get's noticeably hot and softens up filament before entering the hotend. I feel a gear reduction would be the way to go... But I don't wanna be messing too much with my pre-assembled unit yet....
Additionally, in my original extruder, and the replacement extruder body (free of charge, thanks prusa), the filament path is not straight, but bends around the extruder gear without any idler pressure. Not sure this is or should be intentional, certainly increases filament resistance and thus motor requires more motor current...
Anyway, I'll wait a bit and see what Prusa comes up with. But I have absolutely fallen in love with the removable build plate... Sure the quiet printing is amazing too, but for me that's just cosmetics.
Yeah, this is a screw up IMO.... bondtech extruders always used geared steppers and their BGM is a 1:3 ratio like titan. Dropping steps per mm is prone to low current micro-stepping artifacts since it must spin slower/less steps. Course if that's the case, faster print would show less however this would be visible on outside walls and they're set to print slower in slicer profiles. still up for experimentation but i noticed this with my old direct non-geared extruder, faster printing reduced vertical wall artifacts/lines (but increased ringing of course... ). Filament viscosity did too, like lowering the temp (rigid ink pla at 175-180c looked phenominal) or using ABS.
Burning hot motors don't help either...the mk2s motor on silent barely gets warm on 5-10 hour prints. my 22mm pancake motor on titan barely gets maybe 40c... 50c in an enclosure but it's got a gear so it won't melt filament. i think it's vref on tmc2100 is 1v.