First 3d printer - Ender 3 pro

[PekkaNF]

Pekka, we may have read the same anecdotal information, I've read that some of the more exotic magnetic materials will permanently lose their magnetism between 80°-100°C.
....

I saw that one too. But I am more worried about the surface interaction with filamet at elevated temperature. I also tried to find out what chemicals can be safely used for cleaning the print surface without damaging it. I read  that IPA and soap water is safe. I can confirm they are safe. I also read that acetone is bad for it.... didn't try that.

Because the (missing) manual does not say what is safe to use for the print surface AND remove PETG. The surface works exceptionally well for PLA, but PETG sticks to it way too hard. Maybe I should try glue stick or hair spray?

Pekka

[Brass_Machine]

Found this on all3dp

Build Surface

The standard Ender 3 build surface, BuildTak, is the ideal surface for printing PETG with the Ender 3. This material will allow you to have excellent adhesion while providing a more natural way to remove the print due to its flexibility. But be warned: An initial layer height that is too small can cause PETG to fuse to the print bed, making it easy to damage.

If you have equipped your Ender 3 with a glass build plate, you should watch out. PETG is notorious for sticking to the glass so well that it fuses to it. This fusing can be so strong that it removes chunks out of the glass bed, permanently damaging it. If you choose to use glass, use a thin layer of hairspray, glue stick, or specialty bed adhesive.

Covering the Ender 3’s print bed with blue painter’s tape is the best and easiest way to get PETG to have a secure bed adhesion as well as ease of removability. We recommend this method as your default.

Another good option is Kapton tape. This tape will give you the same benefits of using blue painter’s tape, but might not have the same amount of adhesion.

Eric

[PekkaNF]

Thank you Eric. That confirms my experience.

On one ocasion extruder nozzle was too low when I used PETG (but only for skirt) and I can confirm that it REALLY sticks to it. Previous prints with PLA were fine and I did not check the bed level. Still, not sure why the bed was on correct level before and then too close on next print. Same location, same homing, only bed temperature raised from 50->80C.

But also at 80C even when first layer is extruded close to 50% of nozzle diameter (I.E. gap between nozzle and bed is 0,20 mm and nozzle d is 0,40 mm) it sticks to bed uncomfortably hard.

I must say that I had practically non used bed before PETG, I only had used sample PLA filamet prior to experiment and used standard setting with very minor modifications.

[Pete.]

But be warned: An initial layer height that is too small can cause PETG to fuse to the print bed, making it easy to damage.

I wonder, does this mean 'nozzle too close' or 'layer too thin'?

[AdeV]

But be warned: An initial layer height that is too small can cause PETG to fuse to the print bed, making it easy to damage.

I wonder, does this mean 'nozzle too close' or 'layer too thin'?

The latter comes about because of the former... AIUI, the hot glass + hot plastic + pressure from the extruder = fused PETG/Glass... or at least, very solidly bonded.

Can't say I've experienced anything remotely like that. Then again, I can't remember if I re-set the bed height for PETG or not, or whether I just went with what was working for PLA.

[PekkaNF]

I needed to print / slice /adjust flex filament buttons several times. Still I don't have good parameters for this Ninja flexible filament, it seems to be pretty temperamental and took some tries. Finally gave up blue tape and used Ender Pro-bed, just wiped clean with IPA, raised bed temperature to 45C just before first layer (rest of print at 40C) and first layer was printed pretty "flat". Extruder temp was 228C, layers may not be fused extra well together, but I was getting allready some oozing and stringing.

Last hurdle was to adjust height  0,85 mm shorter, or buttons would not "click" reliably.

Round button holes on the panel line up pretty good with the PCB swiches, but extreme arrow button nearly misses the switch. Paralax error on the picture lies more than any politician.

[Will_D]

Any one know how to achieve a filament change in g-code/m-code.

It would be analogous to doing a tool change on a mill?

Basically you slice, generate the g-code, Fire up the editor, go to the particular layer (identified by a comment and also the Znnn comand),

add the unkown m-codes,  and run the code. The printer runs the first layers then pauses, and maybe does an auto filament change or you do it manually and then resume the print.