3D Printing => General 3d printing => Topic started by: BobC on 17 Dec, 2017, 15:18:39 PM

Title: Nozzle Cleaning
Post by: BobC on 17 Dec, 2017, 15:18:39 PM
I've been printing a forest of Christmas trees: https://www.thingiverse.com/thing:1913982, scaled to 33% to fit in the 101Hero and printed in spiral vase mode with 2 base layers using Cura 3.1.

Eventually I started to see some underextrusion due to my nozzle getting clogged.

I tried the "warm yank" method, where you set the hot-end temperature to about 50C, then release the extruder tension and pull out the filament.  This worked well enough, but I was afraid that repeatedly opening and closing the 101Hero extruder door would wear out the screw holes way too fast.

What I'm doing instead is placing a pair of pliers (or anything metal) 1-2 mm below the nozzle then, at normal print temperature, extrude a small amount of filament to form a ball attached to the end of the nozzle (I use Pronterface to do the extrusion).  Then I set the hot-end temperature to 30-50C, and when it gets there I pull straight down to remove the ball from the end of the nozzle.

This does a good job of cleaning the nozzle, with no need to unload and reload the filament.

I'm thinking it should be possible to do this automatically by printing a small part that has enough bed adhesion to resist the upward pull.  Thoughts?
Title: Re: Nozzle Cleaning
Post by: BobC on 23 Dec, 2017, 05:00:10 AM
OMG, tree #40 is printing now.  Somebody either stop me or turn me into an elf.