Experimentation: Print Pausing, Part Insertion, Techniques.

[awerby]

I don't know; it was just a suggestion. If you try it and it works, post back and let us know, okay?

Andrew Werby
www.computersculpture.com

[RobH2]

Sure will.

I have an odd way of changing filament if I'm not worried about a color change occurring. Say I'm going from black ABS to white ABS. What I do is snip the filament off about 10mm above the last spot on the extruder before it dives in and disappears. I then stick a piece of paper towel over that cut end to catch plastic bits and I use the tip of an xacto knife to drill a small conical hole into the end of the filament. I then sharpen the other end of my new white filament that is coming in. Next I hold the new filament up to the extruder and estimate how far it is from that place I snipped that black off at and about 1/3 of the way into the hotend barrel. I mark that on my white filament. Finally, I start the print and as the filament begins to move down I place that sharp point of the white filament into the conical hole of the black filament and gently push to keep then together until the mark on the white filament reaches the extruder. That let's me know the new white filament is in the hot end and being grabbed by the hobbed bolt. And, the sharp filament end inside the conical filament hole is a perfect guide so nothing get's misaligned as the hot end is entered. Then I let go and all is done. It always makes for an interesting color transition too.

I suppose if your really wanted to get clever, you could cut short sections of various colors and then insert them using this method in any order making very fun color variations. Plus, you never have to pause the print if you get good at making that cut, drilling the hole and being ready before the filament gets pulled inside the extruder. Actually, as I think about it, you could cut your sections and predrill and sharpen. Then as you watch a piece about to disappear, you just hold the new one right behind it and so on until you are done. I might just have to play with that one day.

I find it a fast and simple technique. If I change material types, then I have to waste a bit of filament until the new material is coming out. But, we waste so much filament anyway, I don't even sweat that anymore.

I'll report back if I try the "pause/heatgun" technique.

[beerdart]

Rob I think your over thinking the filament change I can change filament in 30sec or so. Just stop print and with hot-end hot release the tension with your thumb and pull the old filament out and insert new. I like to manual extrude till the new color is extruding aprox 1" or so.

[RobH2]

Really, that easily. OK, then I am over doing it. However, if you didn't want to pause the print, my technique could be useful in some cases I think. I'll try your method next time around. I appreciate the guidance.

Edit: One thing I just thought about that's good with your method is that each time you remove that hot filament, you are in effect cleaning the head. I read a post that said to heat and pull several times to get the inside of the print head clean. With your method, especially if you cut off that first 40mm or so (the part that would have trapped debris in it if there were any), you are always cleaning the head just a bit each change. Is that a reasonable observation?

[beerdart]

Ill run a test part with pause as soon as its my turn to use the printer the owner (My Son) is currently printing.

[RobH2]

You need a second printer in that house my friend.

[beerdart]

First test print worked great except in the Gcode the steppers were not locked and I bumped the Y and the white shifted slightly. Running a second test now.

[beerdart]

Or send the boy out to get a job.. LOL

You need a second printer in that house my friend.

[beerdart]

Agree we always change filament with a hot hot-end.

Really, that easily. OK, then I am over doing it. However, if you didn't want to pause the print, my technique could be useful in some cases I think. I'll try your method next time around. I appreciate the guidance.

Edit: One thing I just thought about that's good with your method is that each time you remove that hot filament, you are in effect cleaning the head. I read a post that said to heat and pull several times to get the inside of the print head clean. With your method, especially if you cut off that first 40mm or so (the part that would have trapped debris in it if there were any), you are always cleaning the head just a bit each change. Is that a reasonable observation?

[beerdart]

Second part off im pleased with the results.