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Hi guys,
I just bought PLA PRO plastic to try out since I've only ever printed with the ABS I used for my fan shrouds. Anything I should know before swapping them out and printed? From what I've read: heat up the nozzle to remove the ABS then insert PLA and extrude a bit. Wipe the gluestick off the heated bed. Lower the temperature of the bed and turn on the layer fan. I'm guessing I should use a caliper again and make a custom setting from the PLA default setting.

Anything else? Will that fan turn on on its own or do I do that manually?

So, a couple of things.

Most of these are true for swapping out filament in general, and I wish I knew them when I first started out.

Firstly, never yank out filament when the hot end is at printing temperature. You'll leave a string of filament that will interfere with the new filament you stick in there. It will feel like a jam, but it's a thread of filament getting in the way.

Secondly, no reason to remove the bowden tube, you can do the entire swap with the bowden fully assembled.

For ABS, I can safely remove filament for a swap at 180c, it's hot enough to be pliant, but not so hot as to cause stringing.
For PLA, I'm still trying to figure that out, but I think it's in the 160c range.

Now, if you're going from ABS to PLA, you'll want to make sure you expell all of your ABS from the nozzle when you switch.
In order to do that, you're going to have to extrude a length of PLA at ABS temps, so 135c or whatever you normally extrude ABS at.
That's so you can be sure that the ABS is melted and comes out as part of your purge.

Going from PLA to ABS is even easier, just heat to 160c, remove the PLA, insert the ABS, and extrude at your normal ABS temp.

gestalt73 wrote:So, a couple of things.

Most of these are true for swapping out filament in general, and I wish I knew them when I first started out.

Firstly, never yank out filament when the hot end is at printing temperature. You'll leave a string of filament that will interfere with the new filament you stick in there. It will feel like a jam, but it's a thread of filament getting in the way.

Secondly, no reason to remove the bowden tube, you can do the entire swap with the bowden fully assembled.

For ABS, I can safely remove filament for a swap at 180c, it's hot enough to be pliant, but not so hot as to cause stringing.
For PLA, I'm still trying to figure that out, but I think it's in the 160c range.

Now, if you're going from ABS to PLA, you'll want to make sure you expell all of your ABS from the nozzle when you switch.
In order to do that, you're going to have to extrude a length of PLA at ABS temps, so 135c or whatever you normally extrude ABS at.
That's so you can be sure that the ABS is melted and comes out as part of your purge.

Going from PLA to ABS is even easier, just heat to 160c, remove the PLA, insert the ABS, and extrude at your normal ABS temp.

Thanks man! I'll add this info to the little guide I've been making for myself.

My method is to pull the filament out at a rather low temperature, that allows to pull all of the plastic out with it. In this case, you don't need to extrude a portion of the next filament in order to clean the nozzle out of the previous one.

I heat the nozzle up to something in between 100 and 120°C before pulling the filament of PLA. All of it should come. The temp is around 140 to 150°C for ABS.
What works best for me is to do it while heating up a cold nozzle, and pulling as soon as the tempreature is reached.
If you can see the tiiny bit of plastic that was in the terminal section of the nozzle, then it's a win.

Just cut the filament above what used to be the "plug" => it is the part of filament tht is fatter than the normal section of 1.75mm.

I usually cut it diagonally to the filament section, in order to ease future insertion of the filament... it will find its path more easilly through the extruder, and bowden junctions.