different nozzle diameters on a dual extruder machine

[Bappy1988]

So, I have a replicator dual (CTC clone) and I've got a 0.4mm nozzle in the right, and a 0.8mm nozzle in the left, so I can print fast rough prints, or nice fine prints without messing about with tool changes.

Alas the gpx tool only allows setting the nozzle diameter once per machine :( :(

I can probably figure out making the change to the code to support a nozzle_diameter_override feature on the tool options, but it got me thinking about the printer itself. does the printer's firmware need to know that the nozzle diameter has changed?

as for the change, there's a bit around line 2200 in gpx.c where it is using nozzle diameter as a multiplication factor in working out the volume to extrude, and around 3200 ish where it is overriding the layer height. I haven't yet looked at the code required to read the value in from the ini file though.

I did have a thought... instead of making code changes, could I get away with setting the nozzle diameter of the machine to 0.8 and then overriding the filament diameter from 1.75 to 3.2 on the 0.4mm nozzle and thus cause it to extrude one quarter the length of filament it would extrude if it was a 0.8?