How do you change filament?

[DanPin]

On my stealthburner with Phaetus Rapid0 2 I normally just heat the extruder to 220 and reverse the motor until I can pull out the filament.
On occasion, I am letting some plastic melt in the heat break and then can't get the new filament through the heat break.

My method for clearing this is remove the nozzle, heat the extruder, and poke a 1mm steel rod up from the bottom to clear the plug. If I hold the rod in the heater section, it gets hot enough to melt the plug
and clear things up.

I am curious if others have some tricks to prevent the clogging, or other tricks to clear any stoppages in the filament path.

Thanks,...

 

[lord-carlos]

My unload script extrudes a bit, retracts a bit, waits for about 1 or 2 seconds for the top to cool, and then retracts all the way. I don't know if this will help in your case, but it might.

 

[H4kunaMatata]

On my stealthburner with Phaetus Rapid0 2 I normally just heat the extruder to 220 and reverse the motor until I can pull out the filament.
On occasion, I am letting some plastic melt in the heat break and then can't get the new filament through the heat break.

My method for clearing this is remove the nozzle, heat the extruder, and poke a 1mm steel rod up from the bottom to clear the plug. If I hold the rod in the heater section, it gets hot enough to melt the plug
and clear things up.

I am curious if others have some tricks to prevent the clogging, or other tricks to clear any stoppages in the filament path.

Thanks,...

I heat the nozzle up to 220c for PLA or 240c for ASA and hit unload.
The macro then purges before retracting also known as "tip ramming" for those with MMU without a filament cutter.

These are my macros in case that helps.
They are Ellis macros IIRC

[gcode_macro LOAD_FILAMENT]
gcode:
    SAVE_GCODE_STATE NAME=load_state
    G91
    G92 E0
    G1 E101 F300 # fast-load
    RESTORE_GCODE_STATE NAME=load_state

[gcode_macro UNLOAD_FILAMENT]
gcode:
    SAVE_GCODE_STATE NAME=unload_state
    G91
    G92 E0
    G1 E25 F1000 # purge
    G1 E-101 F1500 # fast-unload
    RESTORE_GCODE_STATE NAME=unload_state

 

[DanPin]

I heat the nozzle up to 220c for PLA or 240c for ASA and hit unload.
The macro then purges before retracting also known as "tip ramming" for those with MMU without a filament cutter.

These are my macros in case that helps.
They are Ellis macros IIRC

[gcode_macro LOAD_FILAMENT]
gcode:
    SAVE_GCODE_STATE NAME=load_state
    G91
    G92 E0
    G1 E101 F300 # fast-load
    RESTORE_GCODE_STATE NAME=load_state

[gcode_macro UNLOAD_FILAMENT]
gcode:
    SAVE_GCODE_STATE NAME=unload_state
    G91
    G92 E0
    G1 E25 F1000 # purge
    G1 E-101 F1500 # fast-unload
    RESTORE_GCODE_STATE NAME=unload_state

Thanks for the g-code examples, I will give them try. It seems like "Tip Ramming" and "Short retract with a dley" accomplish the same thing.
Looking forward to less (or none) clog issues.

 

[Dave32]

Also note that hotend geometry plays a role here too. Prusa, for example, has a specialized version of the V6 heat break that they recommended for MMU users (later becoming their standard part), which has a fractionally wider bore in the "cold" side of the heatbreak that steps down to the normal bore in the "hot" side of the heatbreak, to help make the load/unload more reliable.

 

[DanPin]

Also note that hotend geometry plays a role here too. Prusa, for example, has a specialized version of the V6 heat break that they recommended for MMU users (later becoming their standard part), which has a fractionally wider bore in the "cold" side of the heatbreak that steps down to the normal bore in the "hot" side of the heatbreak, to help make the load/unload more reliable.

Thanks...I am always learning new bits everytime I post a question....or just read the forum in general

 

[majic79]

No I'm concerned. I've gone E3D Revo HF and hadn't considered tip geometry for the ERCF I'm playing with... Balls.