Prusa first layers are not solid?  

RE: Prusa first layers are not solid?

Hi, i have the first printer ever, (mini+) since few days, so i'm not a specialist, but i had similar issue, and in my case solution was to re-calibrate first layer.

And i had to lower down to -1.200, so bit more than i expected from my interpretation of documentation... anyway, now works much better.  🙂

Besides in other topic someone else asked about something similar (it's somewhere in the mini part of the forum) and there i found this file which is useful: https://www.printables.com/model/105404

So just print it and every "marker" change a little value... for example i did like that:

it was printed from right to left, so the initial value (on the right) -1.120, and finally on the left -1.200 which i left for now in my printer, prints looks much better now (the first layer).

So here is closeup of the first strip from right (worst one):

and first from left, (best):

and before recalibration prints were similar to that one you pasted above...

and after another recalibration (i added aronud 0.9 to my initial setting...)

yellow one is much better... maybe not ideal, but still far better than four days ago 🙂

i hope it will help you a bit, i tested also older firmware, and older slicer, but the issue was related to that Z axis...
Now i can print really fast with the 5-1-alpha firmware for mini...

Good luck!

RE: Prusa first layers are not solid?

I found the other topic, check this too: https://forum.prusa3d.com/forum/assembly-and-first-prints-troubleshooting/bad-prints-2/

RE:

mixer3d - you should go much closer to the bed, there should be no gaps between the lines - thus, filament will bond with previous adjacent line making solid surface.

See https://www.printables.com/model/107639-first-layer-calibration-prusa-mini for example model and description with pictures.

RE: Prusa first layers are not solid?

thank you! i will try that, i was wondering about that, if it should be solid surface or it's too much... but it was already after 2am after my last tests 🙂 so had to stop testing...
but i will try to do it now

RE:

Ok, so i did the tests and the outcome was that i had to increase more the depth, so now it's -1.400 and looks that it's the best (before i tried -1.200 which was much better than -0.470 i initially started from without knowing yet how it works...) so:

so from the left it's -1.400 and that looks finally like a solid surface, i tried push bit less:

from left to right (three straps) -1.280, -1.300, -1.320
and some other attempts together:

and i found that the quality of layer (at least to verify weather it's continuous surface ) is nicely visible that way:

(i just put the strap on the screen)

Thank you _KaszpiR_ , and hopefully Deadlyender will solve his issue too... 🙂

RE: Prusa first layers are not solid?

And finally print with the new setting:

so this is the layer now after calibration  ^

and to compare (on top) with the old settings... 🙂

and closeup...

I hope it's good, i read that it can be "too flat" or somethnig like and now the surface is so smooth that you can't feel any bumps with your fingertip, so i will evaluate it on the set of the models i tried before...

from the side of the net there are fine threads, but probably it's not related to the first layer calibration, anyway print looks very good...

RE: Prusa first layers are not solid?

'too flat' usually means it is sticking to the bed so well that it is hard to peel it off and it is possible to damage it.
I had some prints removed too fast and it effectively ended with small plastic fragments to be ripped off from the model because they were sticking to the bed so hard.

Another option is that they can get damaged/uneven when peeing off because they stick to the surface so well that it makes layer uneven or it is visible where tools were used to initiate peeling off print from the baseplate.

All in all you have to decide yourself if you need too much adhesion and risk damaging print on removal or too low and thus risking print coming off during mid print 🙂

RE: Prusa first layers are not solid?

Hi, yes i realized that in the meantime..., since yesterday i did some additonal prints, which really looks, and work much better than my initial prints few days ago. But, i found that they stick too much to the plate, and were really difficult te get out from the plate (cold one, and printed before with PLA, on default smooth sheet). So i recalibrated it a bit, and just printed additonal tests, and will try with those one. So to find sweet spot. So now i'm gonna continue printing to find optimal Z layer range.... and it looks that i have to move from -1.400 to 1.3700 and it seems that for a while i will print with that setting and will check what will change. 🙂

RE: Prusa first layers are not solid?

if a part is hard to remove from the build plate, you can dribble isopropyl alcohol around the base of the model on a cold build plate, and let it soak under the model, then try again, once the adhesion has been reduced

regards Joan

RE: Prusa first layers are not solid?

Yea this was exactly my problem, I dont know if it was because i moved locations or i just did a poor job doing first layer calibration (probably this) but i went ahead and messed around with the first layer calibration and it is now perfect

RE:

thank you JoanTabb for tip 🙂