Can't access "Special Modes"/"Print Sequence" setting on certain printers?

[pozzello 0]

Machine profile for Creality Ender 3 and for  CR10 shows/allows me to select  "one at a time"  (vs default "all at once") mode, but when I select Geetech A20T as the printer, that option is hidden, despite having 'all' config settings enabled.   This seems to be the case in Cura 5.2.1 and 5.3.0...   Any specific reason for this behavior?  Any workaround in config files somewhere?  TIA,  Paul.

 

 

[ahoeben 1,948]

That setting is disabled for printers that have more than one extruder enabled. Workaround: disable all but one extruder

[pozzello 0]

1 hour ago, ahoeben said:

That setting is disabled for printers that have more than one extruder enabled.

 

hm.  I don't really see why that should be the case, but it does seem to explain it... 

 

I suppose it may make some sense for an IDEX, where it may be harder to prevent the second moving print head from hitting an already-printed object on the bed, but for the GEETech a10/20/30/M/T's, they all share the same nozzle, so there's really no extra complexity/risk to allowing 'one-at-a-time'...

 

But even for an IDEX, let me try it at least. It could be made to work if one is careful about it...

 

1 hour ago, ahoeben said:

Workaround: disable all but one extruder

 

How would one do that?  Setting 'Number of Extruders' in Machine settings to 1 (from 8, in my case!) destructively looses any start/end gcode one might have set up, so it's not a very friendly workaround...  Is there another way?

 

Thanx,  Paul.

Edited April 19, 2023 by pozzello
clarification...

[ahoeben 1,948]

The reason for the limitation is that when switching extruders, the printhead may be moved to an arbitrary location (eg to prime or to wipe, or in the case of Ultimaker printers to actuate a lever) by the firmware. This move may make the head collide with previously printed models.

 

You can disable an extruder via the "configuration" selector in the top bar (where you change nozzle sizes and materials).