E3D-v6 changing filament is an issue

Try extruding a bit first - maybe 20 on Cura before retracting or trying to remove the filament. I talked to a Lulzbot Tech yesterday about this problem with ABS (I went to extrude a bit then retract and had the filament stick and would not go either direction) - was able to remove the filament by pulling hard by hand.

He did suggest covering the fan intake and fins with something to warm up the area a bit if things got stuck before taking things apart. Another Tech suggested a few months back suggested the same thing and I think the suffested time was around 10 to 15 minutes.

He said that my extruding then retracting was the suggested method.

I use a cleaning filament when I am switching filament types. After purging out the previous filament, the cleaning filament can be “cold pulled” at a fairly low temperature (100-110c) and usually I can shine a flashlight through the filament path and see it on the other side (in a mirror) when I’m done.

You can usually cold pull PLA and get a clean path. I don’t print much ABS so I don’t have enough experience to say if it can be cold pulled. I do print with PETG and use the cleaning filament as described above when I’m done.

You will have the best results with the V6 if you extrude 20 or 30mm before pulling the filament.

You need to extrude 10mm or so at the printing temperature then drop it about 20 C (from the lower temp of the filament’s printing temperature range) and then cold pull out the filament.

I am curious why you would do a cold pull each time you need to change filament.

If you pull it out when its hot and melted there’s a good chance the filament will cling to the components in its path like hot gum on the ground. Then that filament will cool and cause blockage with no good way to warm it up and soften it. Not a literal cold pull at room temp but rather a warm cold pull where the filament is still warm but too cold to extrude.

Just to be clear, we are talking about the change from ABS to some other filament type like PLA that has a different temperature range. One color of ABS to another color of ABS is much simpler as you can just push the old color out with the new one.

I usually start heating the hot end and pull on the filament around 140 -150(ABS) 120 - 130(PLA), and the filament will come out fairly easily and you can even see the end that was in the nozzle tip. I have done this for several years now, and had a lot of practice doing it this way.

Note: I also started aligning my filament feed path a long time ago.

I haven’t had any trouble switching between ABS, PLA and Nylon by warming to the higher filament temp and pushing the old plastic out. The lower temp plastic doesn’t degrade or burn so fast that you aren’t able to raise the temp and push it out.

Just FYI. It might save you some time and effort.