Only received my printer yesterday, and I don’t understand why before each print, what appears to be at least a 100mm of filament is wasted and ‘pooped’ even though the filament has not been changed ?
Is there a good reason for this in terms of calibration, or does the printer just do it automatically irregardless of whether of not a new filament has been loaded ?
I don’t know the reason for it, but it does it regardless. My best guess is it does it to make sure there is no clog.
How does the printer reliably know the filament hasn’t been changed?
It is 105mm which is about 1/3200th of a 1kg reel. Even at Bambu prices that is less than 1 cent/print.
It is done by the printer profile start up g-code if you really want to change it.
Does somebody know where to change it? In all honesty, cleaning from old filament should be part of filament change process 
Its not something that the printer needs to take care.
I agree it doesn’t cost alot, on the other hand if it is not necessary it shouldn’t be done.
The topic is related to non-AMS start.
For AMS it is maybe different - but also there technology should be smarter
Shows Gcode that controls how much it will extrude.
Thanks,
Actually if would be nice if the Filament Load button was a macro and not just a feed in/out control, and that when pressing the button, the filament would load (the length of the filament path from gear to nozzle) without needing to press the display button 1/2 dozen times, and would then clean & cut-off / poop the overflow.
Right now I have to press the button 1/2 dozen times (press & hold does not appear to work) to load / unload whereas the prusa loads / unloads with a single press, the length of the filament path
So basically create a filament load / unload routine, programatically I don’t think that would be very difficult.
I realise that I may be in the minority not using the AMS, but ATM I dont really have any need to print in multiple colours and may only change the filament maximum once a week.
It does this because it cuts off the filament. So it needs to purge the bit left in the extruder so it has a continuous section without the cut.
@Nimrod: Does you mean that at the start of the print, it cuts the filament and then purge?
@Khrisb: Thanks for the vid, I was in the impression it was part of the internal routine. If everything until print start is part of the machine G-code as well I think I have to dive into it as well
Found another with links to his profiles
Sorry for bringing this one back from the dead, but I’m using the AMS and the printer is purging just as much filament when there is no filament change between prints as when there is a change.
I notice after each print is done, the AMS will pull back the filament to it’s parked state. It seems the previous filament used isn’t being stored anywhere, so it just runs a full purge regardless.
I do agree that this is on the grand scheme a minor problem and not a blocker to anything. I would still love to see this level of refinement out of the box if at all possible. Do others with the AMS have this same behavior?
The printer cuts the filament. The purge is because it doesn’t know what’s in the hot end.
Given that this is gen one tech, I think it’s doing a great job.
Again, the printer is doing a lot more than just loading a single filament etc… I understand though for those without AMS a lot of this isn’t necessary, and there should be an option to turn it all off and go back to basic printer functionality.
I agree with you entirely @I_Anthony ! I absolutely love this printer so far.
Is there any news to this? An option to make it remember the last used color? Printing mainly one color and use AMS to auto reload between spools.