How do you clean clogged nozzles?

How do you clean clogged nozzles? I found out that with my one piece polished barrel, you can actually remove the filament in one piece at room temperature. I find it quite cool, but would you consider it as plus? I made a litle video about it. http://www.youtube.com/watch?v=yh0wP93VrsY

I always thought it was odd that we couldn’t do this.

We were not able to do it, because of the fact, the nozzles are from multiple pieces and the filament forms around the internal imperfections and locks into it. You can replicate this with normal nozzles at temperatures lower then the melt point, like 130C for ABS, but it isn’t reliable and most of the time, you unplug only piece without the very tip, which is most important for cleaning. I would not be able to do this either if the insides wouldn’t be polished.

Does your nozzle have a draft angle to make this easier, or is it just a straight tube?

Straight tube, but it has to be very very smooth. Lemme show you a pic. (My hacksaw skills are bad, it’s been cut at an angle) https://dl.dropboxusercontent.com/u/8967423/nozzle.jpg

That’s pretty. I assume the polish makes extruding take less pressure as well, and isn’t just for this cleaning trick?

When it isn’t polished, it doesn’t work at all. That is why it took me almost a year to make it. At some point, filament is molten enough that it forms around the inside surface and locks into it, but it isn’t molten enough to simply flow.

@Josef_Prusa , since the first i3 shots, I don’t think I’ve ever seen two pictures of your printer with the same extruder mounted. How many different extruder motors are you going to use?

LOL good call :slight_smile: I experiment a lot

IMO it’s a bonus. I’d still heat up the nozzle to remove it (We can get some real crap plastic here in Aus), but if that temp can be heaps lower than currently, I’m all for it!

Have you started selling the Prusa Nozzle ?

Next week Ill start selling dev units on IRC. Then regular ones :slight_smile: Finally!

Can’t wait to buy one

With my current nozzle, I just shove a thin wire up the whole and hope it works. When I fit my new nozzle I hope never to have to do this again.