First Layer - How should a first layer should look?  

Re: First Layer - How should a first layer should look?

i think the first-layer-lines could be more pressed to the printbed, so there's less space between them
Exactly. Lower the nozzle about 50-100um. There should be no gaps between lines.

Re: First Layer - How should a first layer should look?

Okay, thank you! I've sketched a 1mm high object (~50x10mm) with some holes, rounded eges, cutouts, etc. and will print some testobjects while playing around with the live-z-adjustment. I will update this post when i have some results.. thank you 🙂

Re: First Layer - How should a first layer should look?

Hi bastian,

I'm also in the process of calibration. Would you share your 1mm test object to help me out calibrate as well ?

My 1. layer height seems to change during print (without / adjust) and i don't know why yet... Any pointers in the right direction ?

Also I'm having some weird issues on my Prusa logo on the top: http://imgur.com/a/rUrkq

It seems like the infill of the charachters is overflowing or something...

Thanks and good luck to you too

Re: First Layer - How should a first layer should look?

Hey manuel,

it's no big deal - you could also print a rectangle of 10x10mm, but i attach it.
In fact of your picture, i would say: To much filament is pressed trough the nozzle (reduce flowrate? check your noozle-diameter in your slicing-software?).

Re: First Layer - How should a first layer should look?

Hello bastian,

Thank you for the design. I dont use slicer software i print straight from the sd card to eliminate errors on my side in that regard. So the files are presliced from Prusa itself and should print perfectly. I assue it is an hardware problem. Any ideas what to tighten or loosen ? Thanks!

Re: First Layer - How should a first layer should look?

I would say thats a Live-Z-Issue. Maybe you could post a picture showing the bottom of your above object?
Print it again and set the Live-Z-value a little bit higher (maybe 100 um?), and check the results.

Re: First Layer - How should a first layer should look?

Hey there!
I've correct live-z from -0,4720 to 0,4970. What do you think david; is this enough or yould i get it a little bit better?
It seems, that the space between the lines on the left is lower (= better) than on the right, but i think that has to do with the printed object (it was printed with the long side in direction of the y-axis).

Re: First Layer - How should a first layer should look?

Try -0,53. There are still gaps between lines.

Re: First Layer - How should a first layer should look?

Hi

Thank you all for your feedback! Here is the backside: http://imgur.com/a/rUrkq

I wonder why on some parts it looks smooth and on others not. I did not change the z height during that print...

Re: First Layer - How should a first layer should look?

Try -0,53. There are still gaps between lines.

David

Just a thought... With -0.5mm adjustment, would you think that raising the probe by that amount and restarting calibration worthwhile?

Peter

Re: First Layer - How should a first layer should look?

David: Okay, i will try it tomorrow... i've started just a print that will take some time 🙂
Manuel: Maybe problems with the auto-bedleveling? Do you use qualiative filament?

Re: First Layer - How should a first layer should look?

Hello bastian,

Hmm im using Prusa filament for now but will switch later to a bit lower cost i think. But first i want o improve my quality.

How would i detect auto leveling problems ? And fix those ? XYZ Calibration worked fine. The nozzle was quite near the bed when doing the calibatration.

Re: First Layer - How should a first layer should look?

Just a thought... With -0.5mm adjustment, would you think that raising the probe by that amount and restarting calibration worthwhile
I think -0,5 is OK. I use -0,45 for PLA and -0,6 for ABS and still happy with that. I wouldn't mess with that as long as everything works OK and there is enough clearance between the probe and printed object.

Re: First Layer - How should a first layer should look?

I think -0,5 is OK. I use -0,45 for PLA and -0,6 for ABS and still happy with that. I wouldn't mess with that as long as everything works OK and there is enough clearance between the probe and printed object.

OK, just thought it may be a reason why some users are having issues with the probe hitting the part on occasion. I don't have that issue and the largest Z Adjust I have to make is about 30 microns as I have the probe adjusted quite accurately.

Peter

Re: First Layer - How should a first layer should look?

Hi

Thanks bastian i printed some of his test parts.

The results are pretty good i think. But only on these small test pices.

I used normal setting 0.2 detail.

Z Adjust is -0,290

I measured these values with my caliper:

Z = 1.07 (i think this is really good no ?)
X = 39,05 (should be 40)
Y = 9.08 (should be 10)

I think Z is really good but im concerned about x and y. They are off by one milimeter. What would i have to tweak to get them right ?
I guess they correspond the the x and y axis of the printer so could this be a belt issue ?

Thanks a lot!

Re: First Layer - How should a first layer should look?

Your X/Y measured values is probably over/under extrusion.
If you're about to switch to cheaper filament this will be a common problem.

I've bought some PLA from Hobbyking at 15 USD or so / KG, this filament is useless if you need to print something that actually have to be perfect. The diameter of the filament can differ from 1.63 to 1.83 in the same spool. So you'll get a very varying extrusion with that filament. I actually have to adjust the "flow" during print sometimes.

At the moment I'm testing a lot of "expensive" filament, to find one I like and then I will stick to that.

But... to get your bas calibration correct, have you calibrated your steps/mm setting in the firmware?

This is a good guide:
It looks like you are over extruding at the moment looking at your top layer.
I would lower the nozzle as well.

Just to add some personal experience, my first layer is always flat on the bottom when I look at it after the print, but I always have a scratched look on the first layer. Second layer looks perfect though. So its not really a bad thing if the first layer looks a bit rough IMHO.

I have a very long and pretty confused thread here: http://shop.prusa3d.com/forum/prusa-i3-kit-building-calibrating-first-print-main-f6/problem-with-first-layer-t1066.html , you might find something useful there.

Re: First Layer - How should a first layer should look?

Personally, I would look at other things before adjusting the steps.

If the belts are not tight enough you will print objects that are smaller in the X/Y axes than the original model. Because the belt pulleys are a fixed size and manufactured quite accurately, there should not be any need to amend the step values.

Also to get good dimensional accuracy, you need to print the outside perimeter before the loops and infill.

Peter

Re: First Layer - How should a first layer should look?

Personally, I would look at other things before adjusting the steps.

If the belts are not tight enough you will print objects that are smaller in the X/Y axes than the original model. Because the belt pulleys are a fixed size and manufactured quite accurately, there should not be any need to amend the step values.

Also to get good dimensional accuracy, you need to print the outside perimeter before the loops and infill.

Peter

My belts have good tension on them, still my 20mmx20mmx20mm cube prints 19.8mm, 19.8mm, 19.8mm, any tips regarding that?

Re: First Layer - How should a first layer should look?

My belts have good tension on them, still my 20mmx20mmx20mm cube prints 19.8mm, 19.8mm, 19.8mm, any tips regarding that?
Celebrate. 😆 1% accuracy is quite good.