Quote Originally Posted by curious aardvark View Post
just a quickie - filament change advice works perfectly !

Thanks mate :-)
Couldn't find the "change advice" post you talk about but I'll tell you what I've been doing lately. I either added to or started a thread about cleaning clogged nozzles. That talked about heating up nylon in the extruder, then cooling it "some" and then extracting it. The semi-cooled nylon would drag out a perfectly shaped model of the inside of the nozzle, and anything left inside, would come with it. It works fantastically for me.

So, I now have applied that workflow to all my filament even when I'm not clearing a jam. Before I remove or swap a filament, say ABS, I set the head to about 110C and let it sit for a few minutes. Then I slowly pull that filament out with some needle nosed pliers. I grab the filament near the hinge and rest the tip on the top of my extruder body's surface. I then lift the pliers very, very slowly, by the handles. It's sort of like a lever with the pliers tip resting on the extruder and my hand lifting the handles. I lift the filament out mm by mm until it comes free. And, it's shaped like the nozzle's inside with a little tip that was left from the nozzles .4mm opening (or whatever diameter the nozzle is). I then know I got ALL of say, the Black, filament out. So if I put White in now, I have virtually no contamination of color and I know it's clean inside.

This is a shot of the nylon cleaning but it shows what the extracted filament should look like:
CleanHead.jpg