You don't need to purge the nozzle when changing filament.

I know, you're saying, "Wait. What?"

You will see how to eliminate poop and reduce filament change times from minutes to seconds.

The K1 CFS upgrade has introduced many challenges for me.

Often, when purging, the combination of air blast and banging the chute does not shake loose the poop from the nozzle. This may be a problem that I see often because i primarily use PETG which is quite viscus.

When the poop is not released properly, it can drop the poop in front of the poop chute on the print bed. The problem with this is that after the purge process is complete, the first thing the machine does is raise the plate which usually squishes the nozzle directly into the newly dropped poop. The nozzle then proceeds to the prime tower, which can either, with luck, knock the poop off of the nozzle or jam up the x/y causing a layer shift. This will cause the next layer to be out of place and likely when the extruder moves to cut the filament for the next change it will smash all over the inside of the printer. I have had a wire ripped out of my extruder motor because of this thrashing after the extruder lost its position. Super sucks. Not only did I lose the print, I had to order a new motor.

Needless to say the chance of poop getting on your plate or your print is high.

There is a way to eliminate poop during color changes. This method does a single poop at the beginning of the print to introduce the first filament. ONE POOP. No matter the size of your print. ONE POOP.

The basic method is to first change your filament purge volume multiplier to 0.00 and press re-calculate. This should change all calculated purge amounts to 0 cubic millimiters.

The second step is to change your machine settings to purge to the prime tower.

In the multicolor tab of your print settings, change the purge volume to 200-300 cubic millimeters. This number can be modified based on the types of colors you are changing. 100 can get you swapped to the new color but can lead to some color contamination. 500 can guarantee a full color purge but causes a massive prime tower. Adjust as needed. The gcode may not have to purge the entire size of the prime tower as it does have a "value" that it expects to purge and can only print a partial layer on the prime tower and then frame work lines so the next layer can have a stable surface to print on.Settings such as "purge to supports" and "purge to infill" can reduce the amount of prime tower purging required.

In the end you will not get an enormous amount of waste filament. And clean up is super easy. just toss the prime tower and single poop from the bottom of your printer. The other benefit to this is I find that a nozzle purge can take a few minutes. With this method, the filament is cut, retracted, refed to the extruder, waits about 10 seconds and starts printing the prime tower immediately, totalling about 30 seconds of filament change time (not accounting for the slightly increased time to print the larger prime tower).

Just stop pooping. Save time and sanity.

Hope you found this helpful. Happy Printing.

Poop is a Lie