M600 Filament Change is a FAIL
I really can't believe how bad the M600 command is implemented - it is a total fail. It relies on "just-in-time" human reflex to capture the extruded filament before returning to the print. It also makes a major mistake by not lifting the print head to a reasonable z distance.
As far as I can tell the M600 macro is to raise the head a couple of mm from the last layer, go to the corner, back out the filament and wait for the user to load the new filament. The first issue here is that at very low Z layers the print head is right up against the bed. The print head SHOULD go up a few mm above the piece WITH A MINIMUM DISTANCE of say z=80 or something where the user can access it. I dare anyone to try a filament change at z=1mm and not end up with a hairball.
The next issue is after filament change it spits out additional filament and immediately returns to printing. Judging by prior comments many folks are bewildered as I am why it is programmed to do this. It should return with a zero or slightly negative extrusion rate with nothing being extruded. The way it behaves now offers a great way to screw up your print.
You can insert your own gcode to actually fix this, which begs the question why isn't the M600 command programmed to work correctly? Before the M600 command you can move the head to a z=100 or higher so its above your piece. After the M600 command (and the associated incorrect extrusion) you can command it back to the resume X/Y location (without changing Z) with a zero or slightly negative extrusion so that you have a few seconds to access the print head in case you missed anything. Unfortunately their is no PAUSE for user input on Marlin which should be the next command so you have time to make sure all filament is cleared, however it seems perhaps the G4 Dwell command might be useful here (haven't tried that yet).
Why can't PRUSA make the M600 work in a normal way???
Re: M600 Filament Change is a FAIL
Hi Steve,
I last did that Saturday afternoon.
large red disc 1mm thick,
black text 1mm thick
Ok M600 command was at 1.2mm... so I failed ... but it's so close it doesn't make a difference in my book
printed disc, at Z +1.2mm action stopped, printer moved platten to reat and extruder to right and started bleeping,
I was in a different room...
when I came through, I pressed the button and removed the red filament.
Click to confirm filament removal of filament...
Insert black filament...
waste filament piles up below extruder
Grab filament with Long nose pliers but don't pull off...
click to confirm colour clear
as printer extrudes the last worm, and moves back to print, the waste pile stays attached to the pliers and the extra worm rips off the extruder...
Yes, it's not ideal
but it does stop the crap on the print
[attachment=0]20180429_192444[1].jpg[/attachment]
chamfer on edge of Red panel, superglued to chamfer on Black housing
lighting to be provided by bicycle RED Led light from Pound Shop
regards Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
Re: M600 Filament Change is a FAIL
Oh, half way through the first layer of black lettering, I got a false filament out error, so I removed and re inserted the black filament, using the long nosed pliers again, and as soon as It was printing again, I turned the filament sensor off, and pressed the button to clear the message and resume printing...
as far as I am concerned, the filament sensor is more of a hassle... YMMV
however if you have the time and patience to revise the M600 function , I am sure the whole Marlin user group including All Prusa users would be pleased to use the improved functionality, that's one of the beauties of the Open source program...
if you watch this video, I think you will see this completely different printer, also spew out waste material after restarting with new filament...
so It's not a 'Prusa Only' issue
regards Joan
regards Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
Re: M600 Filament Change is a FAIL
Oh, half way through the first layer of black lettering, I got a false filament out error, so I removed and re inserted the black filament, using the long nosed pliers again, and as soon as It was printing again, I turned the filament sensor off, and pressed the button to clear the message and resume printing...
as far as I am concerned, the filament sensor is more of a hassle... YMMV
however if you have the time and patience to revise the M600 function , I am sure the whole Marlin user group including All Prusa users would be pleased to use the improved functionality, that's one of the beauties of the Open source program...
if you watch this video, I think you will see this completely different printer, also spew out waste material after restarting with new filament...
so It's not a 'Prusa Only' issue
regards Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
Re: M600 Filament Change is a FAIL
Oh, half way through the first layer of black lettering, I got a false filament out error, so I removed and re inserted the black filament, using the long nosed pliers again, and as soon as It was printing again, I turned the filament sensor off, and pressed the button to clear the message and resume printing...
as far as I am concerned, the filament sensor is more of a hassle... YMMV
however if you have the time and patience to revise the M600 function , I am sure the whole Marlin user group including All Prusa users would be pleased to use the improved functionality, that's one of the beauties of the Open source program...
if you watch this video, I think you will see this completely different printer, also spew out waste material after restarting with new filament...
so It's not a 'Prusa Only' issue
regards Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK