Can anyone explain why Simplify3D defaults to an extrusion multiplier of 0.9 for PLA?
Something to do with PLA expanding whilst hot?
@Mark_Wheadon That seemed odd to me, I bumped it up to 100% as it appeared to be under extruding, so far so good.
As did I, but I’m starting to come around to thinking I’m over extruding (print-in-place jointed prints are too tight or completely frozen for example), which would make the default about right. I can find references to the fact that it’s supposed to be 0.9, including from Simplify3D themselves, but nothing saying why…
Ditto - the company I work for supplies a Simplify profile and the first thing we did was bump the extrusion multiplier up to 1.0. @Simplify3D you’re doing something wrong there… even the profiles we submitted to you, someone modified and screwed up our profile doing this.
Best I can figure is that since prints come out cleaner when underextruded and PLA is mainly used for visually pleasing prints they defualted the extrusion multiplier to under extrude. This ofcourse comes at the loss of prints being water tight and losing a tiny bit of strength.
I also can’t quite make sense of that… So I bumped it up
I actually reduced it slightly to 0.89. When printing thin walls this is used to calibrate thickness. I now get perfect 0.5mm thick walls.
@Richard_McKenna And your printer was already calibrated by extruding (say) 100mm and checking that it really was 100mm, adjusting ESTEPS accordingly?
@Mark_Wheadon yes
Extrusion multiplier is entirely a hardware-specific parameter, so the defaults are completely meaningless unless you’re using a pre-made profile that is already tuned for a specific printer. The starting 0.9 value is a ballpark guess that you’re expected to tune.
Some of this confusion comes down to a different calibration philosophy from what y’all are probably used to. With S3D, you don’t need to set E-steps by extruding 100m of filament, and you don’t need to measure a single-wall calibration box. You just set E-steps to whatever your extruder hardware’s theoretical value is (based on hob diameter and gear ratio) and then adjust extrusion multiplier by printing a few 100% infill calibration boxes until you get the right amount of filament. It’s a really simple approach and makes great prints.
The 3d printing world is insanely fragmented. Not everybody does stuff the same way. A number of major slicers calibrate volume the same way as S3D, like the Makerbot Desktop / Makerware / Miraclegrue / RepG lineage.
@Ryan_Carlyle I can understand that philosophy if you are only ever going to use the same software always. I would rather have my firmware have the correct configuration regardless of the software used, based on the hardware, then maybe tweak the extrusion multiplier for different filaments, print types, etc in each of the software packages…
But, like you said there are many different ways to skin the apple.
@PrintinAddiction Different slicers calculate extrusion volume and do toolpath generation in slightly different ways, so you’re always going to need different settings for each slicer. Likewise, none of the slicers really care what your firmware E-steps is, or even that E-steps is right in the first place – you can make them all print just fine if you set your software to suit whatever the firmware already thinks. So there’s no reason to change firmware config when switching slicers.
I get my best results at around 1.0 regardless of the plastic type or slicer.
0.9 comes back from the times ABS was default material. The thing is ABS is softer and will give in deeper in the hobbled wheel than stiff PLA. This in fact gives you different effective working radius of the hobbled wheel and thus different distance extruded under same conditions and that’s all folks. Really nice to see how quick some of the basics get lost…speaking of, I really miss @nophead
@Ryan_Carlyle I think we are in agreement, I change the firmware (or config file in smoothie) when I change the hardware (hobbed gear/ bolt / upgarding to a titan/ etc…) I also have many print profiles for different types of prints, but my point was that the esteps should be set correctly in the firmware first, then tweaked as needed in the various slicers. You should not compensate an incorrent estep setting by using the extrusion multiplier.