Notifications
Clear all

Any way to disable mmu temporarily?  

  RSS
.h
 .h
(@h)
Eminent Member
Any way to disable mmu temporarily?

Hi all,

 

I have some filament that won't print thru the mmu.

Some are a little bit thicker and have more friction in the tubes, some are to flexible like very soft tpu.

At the moment I disconnect the mmu and feed straight into the extruder.

 

Is there any other way to bypass the mmu without disconnecting it?

 

TIA

 

cheers

.h 

Posted : 15/01/2022 8:00 pm
.h
 .h
(@h)
Eminent Member
Topic starter answered:
RE: Any way to disable mmu temporarily?

unplugging the power from the power supply to the mmu does not work, the circuit gets the power from the other board.

Is there a pinout available for the socket on the mainboard which connects to the circuit of the mmu?

Posted : 05/02/2022 6:30 am
jsw
 jsw
(@jsw)
Famed Member
RE: Any way to disable mmu temporarily?

I installed a switch to break the power (DPST, breaks both legs, both of the big red and black wires) and the little switch enclosure is in the Prints section.

There are two tapped holes in the MK3s frame that are right there, unused, and just waiting for something like this.

I usually use the machine as a single color, with the Bowden tube disconnected, and filament just fed in to the extruder.  When I want to go multi-color, it's just a matter of reconnecting things and turning on the switch again.

Posted : 05/02/2022 7:10 am
.h
 .h
(@h)
Eminent Member
Topic starter answered:
RE: Any way to disable mmu temporarily?

Cool, I just interrupted one wire, maybe that’s the reason why it is still running, when switched off.

 

I’ll try with both interruptions.

thx

Posted : 05/02/2022 11:44 am
Robin
(@robin)
Prominent Member
RE:

You can just remove the PTFE tube between MMU2 and extruder. Just let everything else untouched, use GCODE for MMU single mode print and let the MMU load filament into the air, at the moment where the filament normally reaches the extruder just feed you desired filament into the chimney of the extruder. Printer and MMU will think everything is ok and print as usual. You can cut the filament sticking out of the MMU (as long as the FINDA is still triggered nothing will happen) or just leave it (it curls and is no big deal most of the time). When print is finished, the extruder will spit out the filament and the MMU will retract the other filament. Just replace the PTFE tube and everything ist back to normal MMU operation.

I use this method for certain TPUs that will not properly load via the MMU. Works all the time...

If at first you don't succeed, skydiving is not for you.

Posted : 05/02/2022 12:41 pm
.h
 .h
(@h)
Eminent Member
Topic starter answered:
RE: Any way to disable mmu temporarily?

Never tried this. Will try it thanks.

Posted : 06/02/2022 5:31 am
Robin
(@robin)
Prominent Member
RE: Any way to disable mmu temporarily?

If the filament is very soft it may not trigger the IR sensor while loading (if it is compressed by the gears too much). If that happens, the MMU will not stop feeding filament in the air. To recover just press in the lever on the right side of the extruder chimney to trigger the sensor, this will make the MMU stop pushing and complete the loading. During print the IR sensor is ignored anyway, since the printer thinks it’s having the MMU and FINDA in operation…

If at first you don't succeed, skydiving is not for you.

Posted : 06/02/2022 9:24 am
You liked
Share: