That's if I go into the G-code to make the pause "automatic"... for which I can see the benefit: obviously the print pauses at the right point without intervention.
OTOH, if I just manually pause the print without having changed any G-code, I'm guessing in that case I'd have to send the extruder reset manually?
Changing Filament Mid Print?
Re: Changing Filament Mid Print?
I wouldn't care to try it but you can always give it a shot and see what happens. 
Re: Changing Filament Mid Print?
You can assign buttons in the control panel UI to execute arbitrary lumps of gcode. Similarly with Octoprint.
Re: Changing Filament Mid Print?
So... I went the conventional route and modified the G-code.
When code snippet was executed, the bed dropped and the printer seemed to pause... for a moment, and then resumed printing. I'm pretty sure I didn't hit the "Resume" button, and my G-code definitely had the "M25" pause command. I was not printing from the SD card though... I had loaded the G-code into S3D directly and was printing over USB. In that case, is M25 (pause SD printing) not the right command? Should I be using "M226" (Gcode Initiated Pause)?
In any case, I paused manually, completed the filament change, manually sent the "G92 E0" code to make sure the extruder was zeroed... and that worked perfectly. So I wound up giving it a shot involutarily.
When code snippet was executed, the bed dropped and the printer seemed to pause... for a moment, and then resumed printing. I'm pretty sure I didn't hit the "Resume" button, and my G-code definitely had the "M25" pause command. I was not printing from the SD card though... I had loaded the G-code into S3D directly and was printing over USB. In that case, is M25 (pause SD printing) not the right command? Should I be using "M226" (Gcode Initiated Pause)?
In any case, I paused manually, completed the filament change, manually sent the "G92 E0" code to make sure the extruder was zeroed... and that worked perfectly. So I wound up giving it a shot involutarily.
Re: Changing Filament Mid Print?
Well, crap - I just finished the other write-up. 
Good for you! - I prefer to print over USB for small stuff....if that works, I'll be using it in the future!
Good for you! - I prefer to print over USB for small stuff....if that works, I'll be using it in the future!
Re: Changing Filament Mid Print?
If you are not printing through SD, you need to use a different method. A "host pause" is a command that is trapped by the host program (the thing sending gcodes over USB) to pause the sending. Different hosts use different methods. Octoprint uses M0, which is fairly common. I think S3D might use M0 or @pause, perhaps sent as a comment; I haven't really investigated.