How to eject high t...
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How to eject high temperature material  



I've been printing PA6 Nylon some time ago and it just wouldn't eject.
Button on the printer -> no luck
Eject from AutoMaker -> no luck
Remove stuck material routine -> nope.

This is how I got around it:

- Go to C:\Program Files\CEL\Common\Macros
- Edit eject_stuck_material#RBX01-S2.gcode

Change temperatures to something adequate
;Eject Sequence
M104 S240 ;Set & heat nozzle to eject temp
M104 S220 ;Go to snap temperature

Now just eject material, fail that process, eject stuck material, profit.

Is there any other way to do it?
Wouldn't it be logical to set eject temperatures based on actual loaded material? Like a fraction of used hotend temperature?

We have been planning for a while now to add an Eject Temperature figure to the material profiles or to the Head file using the previous  used temperature (already used to suggest a purge). It was made complicated by the available space on the EEPROM on the reel and the need for both firmware and software changes so has not yet been implemented.

2 Answers

I think you can use the following macro system to send these more easily (haven't tested so please take care, my Robox is on Liams desk because he is printing some power tool prototypes and needs 2 Robox...because he is greedy...)

If you type a macro name into the gcode entry box in AutoMaker it will run that macro, it has a clever system built in which will select the correct macro depending on what head you have selected and other variables.

Take a look at the files here:


C:\Program Files\CEL\Common\Macros\

Note the names are repeated with a difference after the #. If you were to type the first part, eg "eject_stuck_material" into the gcode entry box, the appropriate file would be called.

Using this you could create an eject_nylon macro, save it in this folder and test it by typing the name. Once you have it working nicely you can copy it several times and add the extra # information to the name to create a set of variations, each file can have slighly different content inside it.

Below code is from "eject_stuck_material#RBX01-S2.gcode"

M103 S ;Set & heat first layer nozzle temp.


M106 ;Fan on Full
M109 ;Wait for Nozzle to get to temp.
G4 S5 ;Dwell
M129 ;Head LED on

;Short_Purge#N0(Single Material Head)
G0 Y-6 X11 Z8
G0 Z4
G1 Y-4 F400
G36 E1200 F400
G0 B1
G1 E2 F200
G1 E30 X23 F100
G0 B0
G0 Z4.5
G0 Y3

;Short_Purge#N1 (Single Material Head)
G0 Y-6 X36 Z8
G0 Z4
G1 Y-4 F400
G36 E1200 F400
G0 B1
G1 E4 F300
G1 E30 X23 F100
G0 B0
G0 Z4.5
G0 Y3

;Eject Sequence
M104 S160 ;Set & heat nozzle to eject temp
M109 ;Wait for nozzle to get to temp.
G0 E-50 ;Create a small ‘neck’ in the filament which can be snapped easily
M104 S125 ;Go to snap temperature
M109 ;Wait for nozzle to get to temp.
G0 E-1500 ;Eject Filament



Note the final line "Macro:Finish-Abort_Print", this is calling a macro from within another macro. If you are repeating code several times you can save it as it's own macro and call it as in this example.

For official support please create a support ticket using this link


I'll make macro on AutoMaker update this week.
Will call it [eject_you_fckr]
I really don't know why I didn't think of that before.


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