1 Topic by TinaMarieF

  • TinaMarieF
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Topic: How to swap filament?

Okay, this is the dumbest question ever:

How do I swap out the filament?  I've been doing what the guy who sold me the printer said, which is to heat up the extruder, pull out the old one while it's retracting, then hit extrude and push in the new one.

Except I'm ending up with bits of filament stuck, sometimes above the hot end.  It's really bad switching from ABS to PLA, because then I have bits that melt at different temperatures.  Even with an ABS/ABS swap, sometimes I'm getting residue from the first color well into my second print.  The other day I got a blob of purple out, and I haven't used that in a week.

Am I totally doing it wrong?  Is there a better way?

2 Reply by adrian (edited by adrian 2013-04-19 04:21:21)

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Re: How to swap filament?

I tend to do what you are doing above - but I keep retracting till it falls out from between the tensioner arm and the hobbed cog itself - i dont ever 'pull it out'... so you sometimes have quite a melted length which I just snip off.

3 Reply by IanJohnson

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Re: How to swap filament?

Once the filament has retracted past the gear and it is stretched and melty, I pull very slowly and gently.  I want to give it a couple seconds to harden as it comes out of the hot end, and I keep hitting the retract button so any clumps or blobs don't get caught on it.  If I can keep the thin thread of melted filament from breaking as I pull it, then more of the plastic will come out.  Then when I put the new filament in, I usually run 300mm or so to purge the old color before starting the print.

4 Reply by Stoney

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Re: How to swap filament?

I undo the tensioner and do it all by hand, pull the old filament out slowly then insert the new one, push in a little, then do up the tensioner and extrude for a while.
then i print something small and unimportant .. sometimes the colour mixes are quite cool.

5 Reply by Skyblue

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Re: How to swap filament?

I also have had issues while changing filament.  Tried the method above, but had problems getting it out.  I now just cut filament, and feed new filament in on top of old.  Works better and have had few problems doing it that way.  Extrude until old color is gone, and continue printing.

6 Reply by DePartedPrinter

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Re: How to swap filament?

Skyblue wrote:

I also have had issues while changing filament.  Tried the method above, but had problems getting it out.  I now just cut filament, and feed new filament in on top of old.  Works better and have had few problems doing it that way.  Extrude until old color is gone, and continue printing.


How do you keep the new filament from sliding past the old when feeding it in?

SD2 with E3D, SD Press, Form 1+
Filastruder
NYLON (taulman): http://www.soliforum.com/topic/466/nylon/

7 Reply by TinaMarieF

  • TinaMarieF
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Re: How to swap filament?

IanJohnson wrote:

Once the filament has retracted past the gear and it is stretched and melty, I pull very slowly and gently.  I want to give it a couple seconds to harden as it comes out of the hot end, and I keep hitting the retract button so any clumps or blobs don't get caught on it.  If I can keep the thin thread of melted filament from breaking as I pull it, then more of the plastic will come out.  Then when I put the new filament in, I usually run 300mm or so to purge the old color before starting the print.


Ah ha!  This sounds like what I need to do.  My thread is breaking pretty early, so I'll try slowing the retraction way down and pulling only very gently. 

Thanks to everyone who offered suggestions!

8 Reply by markm

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Re: How to swap filament?

DePartedPrinter wrote:
Skyblue wrote:

I also have had issues while changing filament.  Tried the method above, but had problems getting it out.  I now just cut filament, and feed new filament in on top of old.  Works better and have had few problems doing it that way.  Extrude until old color is gone, and continue printing.


How do you keep the new filament from sliding past the old when feeding it in?

Not sure if he does it the same way I do, but I cut it, then extrude until it's past the motor, then start feeding the new one, which pushes the old piece through.  Haven't had any slip yet.

9 Reply by Skyblue

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Re: How to swap filament?

If filament won't go in, I retract and cut again, trying different angles of cut if first won't go in.

10 Reply by mr_tim34

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Re: How to swap filament?

I cut the old one off and butt the new one against the cut end and push it on through. This usually works ok, every once in awhile the new filament will slip off the old one and stop advancing. If this happens I  take off the tensioning spring, retract the arm and use a paper clip to push the old color into the peek, replace the tensioner and feed the new color in. If the color change doesn't matter I'll let it go, if it does I'll extrude until  I get the new color.

TiM