Under/Overextrusion Due To Change In Layer Height  

Re: Under/Overextrusion Due To Change In Layer Height

How did you come at these settings at the first place ?

Re: Under/Overextrusion Due To Change In Layer Height

The extrusion multipliers are what I needed to get smooth 100% infills and correct dimensions for parts. Why such weird %'s ? Not sure- I have calibrated e-steps.

I started with .2 and got that dialed in. It was when I started .05 that I noticed huge gaps between infill lines and had to drastically increase the multiplier.

Slow speed is for small parts and because I needed better first layer adhesion.

Re: Under/Overextrusion Due To Change In Layer Height

In Slic3r, Prusa includes custom gcode in the printer settings to set extrusion to 100 for 0.05mm layer heights, 95 for others using the M221 code, so you're not off base with your approach. If you're having issues, you could try mimicking Prusa's settings in Cura. I personally hate the way they do it, so remove that line and do any adjustment on a per-filament basis.

Slow 1st layer speed is always a good idea. No sense rushing only to have to start over.

Re: Under/Overextrusion Due To Change In Layer Height

@Shakalakakan. From my expirience flow settings should not vary more then +/- 5%. Otherwise the problem is somewhere else. Keep in mind that Prusa provides profiles for all pupular slicers and for example your Hatchbox PLA is listed and tested, so in normal conditions nothing to change.

@bobstro. We are talking about M221 S{if layer_height==0.05}100{else}95{endif} line in starting script ? First, the minimum I expect is that the line is is mentioned in Slic3R changelog. Second, not mandatory but it will be really nice from Prusa to explain.

Re: Under/Overextrusion Due To Change In Layer Height

[...] @bobstro. We are talking about M221 S{if layer_height==0.05}100{else}95{endif} line in starting script ? First, the minimum I expect is that the line is is mentioned in Slic3R changelog. Second, not mandatory but it will be really nice from Prusa to explain.
Yes, that's the line. I read a full description somewhere, but sadly didn't save the link. Here's a partial discussion. I'm not sure if or how this correlates to the changes in FW 3.2.1. It sounds like the OP is adding essentially the same thing to Cura, just with different values.

Re: Under/Overextrusion Due To Change In Layer Height

In Slic3r, Prusa includes custom gcode in the printer settings to set extrusion to 100 for 0.05mm layer heights, 95 for others using the M221 code, so you're not off base with your approach. If you're having issues, you could try mimicking Prusa's settings in Cura. I personally hate the way they do it, so remove that line and do any adjustment on a per-filament basis.

Slow 1st layer speed is always a good idea. No sense rushing only to have to start over.

I don't see M221 in Slic3r gcode. I'm on Slic3r 1.38.7. It does sound like it tackles the same problem though.

@Shakalakakan. From my expirience flow settings should not vary more then +/- 5%. Otherwise the problem is somewhere else. Keep in mind that Prusa provides profiles for all pupular slicers and for example your Hatchbox PLA is listed and tested, so in normal conditions nothing to change.

Hmm interesting. I mimicked Cura settings in Slic3er and it was again 85% for .2mm. For .1 it was 95% and at .05 it got wonky. I noticed the first layer was way underextruded whereas other layers were more on the mark-but this was still at 130% flowrate. The first layer I had printing slower than the rest. The gradual Increase in flow needed for smaller layer heights and the wonkyness mentioned makes me think there is some non-linear behavior between the pressure in the nozzle/extruder and the flowrate where once the pressure drops below or rises above a certain threshold due to different speeds/layer thicknesses the actual flowrate deviates from the calculated. I'll have to try cleaning the nozzle thoroughly. Since I'm using the Cura settings provided by Prusa and hardly anyone else is experiencing the issue It makes me think it must be the hardware.