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adam.o3
(@adam-o3)
Active Member
Warping issues

So I'm rocking an MK2S with the first spool of filament (PLA). I'm printing at 215/55 with a live Z of ~710 ish (still narrowing it down, but I've determined that 710 is pretty close). I've been having issues with warping and shrinkage after 10-20 layers while printing large flat surfaces. The base layer appears fine and it even looks perfectly smooth underneath, but after a bunch of layers things start having issues.

I heard it suggested that it may have to do with me needing an enclosure, as the printer is near a window and may be subject to drafts.

I also printed this thing to try and determine if maybe its a bed level issue:
https://www.thingiverse.com/thing:1831902

It basically covers the whole bed with a single layer. During printing, it seems to print it in such a way that it prints only sections and jumps around, probably because of how the gcode is generated.

For some reason, it seems to be printing it at different thicknesses and its causing all sorts of weird problems. Also the warping issue seems to exist on this as a base layer too for some reason.

Why is it doing this and how do I fix it? It is very clear where the issue crops up and does not seem to relate to the bed level adjustments because of the way the lines are clearly drawn on the print.

Thoughts?

Postato : 20/02/2018 5:56 am
digibluh
(@digibluh)
Reputable Member
Re: Warping issues

nozzle too close....

Postato : 20/02/2018 7:18 am
Sidbitters
(@sidbitters)
Eminent Member
Re: Warping issues

You need to perfect the z level in the center and then use bed level correction to adjust for the rest. I have a couple of spots myself that hyperfine bed leveling can't quite correct but it's pretty good.

Postato : 20/02/2018 3:23 pm
adam.o3
(@adam-o3)
Active Member
Topic starter answered:
Re: Warping issues

Here is the thing I don't get though, if the head is too close, why do two sections of a square have completely different thicknesses off of a distinct point where the head started printing again.

Or is that just the slicer being terrible?

Postato : 20/02/2018 7:11 pm
Nikolai
(@nikolai)
Noble Member
Re: Warping issues

If your nozzle is too close, there is not enough space for plastic to stay in the designated line. So you squish it to the neighbor line. If the neighbor line is printed immediately after the previous line, the plastic is still hot and melt together. If you print it a little bit later, then the squished plastic lays down on top of the previous line. Then you see a different areas.

Anyway, as already mentioned adjust the Z-Height.

Often linked posts:
Going small with MMU2
Real Multi Material
My prints on Instagram

Postato : 20/02/2018 7:55 pm
adam.o3
(@adam-o3)
Active Member
Topic starter answered:
Re: Warping issues

So I think I figured it out. After extensive prints and re-prints of the calibration surface in conjunction with your advice, I discovered that it was a combination of too much negative live Z and under-extrusion. According to my math, my extrusion should've been at 105

I tried reducing my Live Z but it gave me very brittle prints with lots of gaps. So I upped the extrusion to 109, gave the bed more heat while printing and it resolved the issue (at least on my first try, we shall see if I'll get consistent results).

Thanks for getting me on the right path!

Postato : 21/02/2018 6:09 am
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