Slic3r Prusa Edition layer height limits  

Re: Slic3r Prusa Edition layer height limits

I thought I would share a response I got from a developer on the github site:

This is regarding Slic3r Prusa Edition, version 1.36.2 (latest as of this post).

I noticed in the default Printer Settings --> Extruder 1 for the "Original Prusa i3 MK2" preset, the Layer height limits are set to Min: 0.07 and Max: 0.25. Shouldn't this be set to Min: 0.05 and Max: 0.35 (guessing the max based on the included 0.35 FAST print settings) ?

Dev --> Not really. The layer height limits were optimized for the particular
extrusion width. Unfortunately the print & printer settings are not quite
independent. The 0.35 FAST draft print settings is a kind of a hack. It
prints with high layer width and an unusually wide extrusion lines. There
is no other way that the 0.4mm nozzle would print a 0.35mm layer height.

This kind of has me questioning all the other default settings for things such as speed. I noticed a lot of the settings there are different than the Slic3r defaults it shows when you hover over a field. For example, Perimeter speed is set to 40mm/s, but Slic3r says the default is 60.

Thanks for any advice!

Dev --> The "default" shown by slic3er is a historical value chosen by the original
author of Slic3r and they are hard coded into Slic3r. We plan to adjust
these "default" settings to the defaults of the MK2 printer one day.

Re: Slic3r Prusa Edition layer height limits

And my reply to him:

Thank you very much for the reply and info. So what you are saying is the true(non-hack) layer height max is 0.25? I was hoping to figure out a 0.25 or 0.30 setting since I have some prints where the majority of the item is not visible. Can I use the 0.20 preset and just change the layer height to 0.25? Or are there other settings I would need to modify for it to work right?

I still don't quite understand why the 0.07 min is not 0.05, but as long as that setting is not preventing me from doing a correct 0.05 layer height, then I guess it's ok. I was just worried that the setting was incorrectly limiting my min layer height to 0.07. Related to this, why is the variable layer height(awesome feature!) limited to 0.07 and not 0.05?

Thanks again!

Re: Slic3r Prusa Edition layer height limits

As far as I know, the Mk1 and Mk2 both had minimum layer heights of 50 microns, but with the MMU and the lower E-Steps/mm for the BondTech filament drive pulleys, the minimum was raised to 70 microns.

I use KISS and I print using the automatic layer height (adaptive, based on Stepover) feature between 70 and 320 micron layers with the MMU without issue (but obviously the tower is quite large with small layer heights.

Peter

Re: Slic3r Prusa Edition layer height limits

Thanks Peter. The website and all documentation says 0.05 ( http://www.prusa3d.com/ ). Maybe they should change it to 0.07 to avoid confusion? Of course that small of a difference is basically nothing, but still.

Is there any advantage to using KISS over Slic3r? Sorry I'm sure there is a topic on this already, I'll search. I like the adaptive layer height on Slic3er, but it sounds like KISS has that as well.

Re: Slic3r Prusa Edition layer height limits

Thanks Peter. The website and all documentation says 0.05 ( http://www.prusa3d.com/ ). Maybe they should change it to 0.07 to avoid confusion? Of course that small of a difference is basically nothing, but still.

Is there any advantage to using KISS over Slic3r? Sorry I'm sure there is a topic on this already, I'll search. I like the adaptive layer height on Slic3er, but it sounds like KISS has that as well.

Single filament printer can still print 50 micron layers, so nothing there needs changing.

KISS vs Slic3r. Don't really want to get into that discussion (again), but KISS does things what Slic3r does not and vice versa. However, these two really are (IMVHO) the best slicers available for this printer; the others are so far behind.

I do find that KISS generates G-code which is more efficient and generally prints take between 60% and 90% of the time of Slic3r prints.

Peter

EDIT: There's a great starter tutorial here:

Re: Slic3r Prusa Edition layer height limits

Oh, sorry I missed the part about MMU in your other reply regarding minimum layer height. I'm still not sure if I need to adjust the min layer height limit to 0.05 in order to truly print at 0.05 layer height. I don't think so, because I can set the layer height to 0.01 in slicer and it doesn't complain.

If KISS can generate faster g-code, that is a huge advantage. I'll give it a try! Thanks for the tutorial.

-Brian.

Re: Slic3r Prusa Edition layer height limits

> As far as I know, the Mk1 and Mk2 both had minimum layer heights of 50 microns, but with the MMU and the lower E-Steps/mm for the BondTech filament drive pulleys, the minimum was raised to 70 microns.

We have tested the minimum layer height with the variable layer height feature and we had issues with the print quality on some printers with some filaments. At 0.05mm layer height, a lot of pressure is required for some high viscosity filaments as PLA to flow nicely. At 0.07mm, we had reliable results. So your mileage may vary, but with 0.07mm you are on the safe side.

Re: Slic3r Prusa Edition layer height limits

Thanks bubnikv, that makes a lot of sense. It doesn't seem like the layer height limit settings in Slic3er really limit anything. Maybe those settings are just informational, or are those settings actually used by the variable layer feature?

Re: Slic3r Prusa Edition layer height limits

These settings are used by the variable layer height feature to limit the editable minimum / maximum layer height.