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ABS VS PETG
Posted: Tue Mar 17, 2015 1:54 am
by jereywolf
Pieces that I usually run with ABS I tried in PETG and found a loss of detail. The pieces that should be like small mounds have become a single strand. I hope that this has to do with my settings.
ABS on the right
My PETG was at .25mm layer height
printing speed 4000mm/min
255°C
retract 2.0mm
no coast or wipe
It was run after getting everything calibrated.
Let me know if you see anything obvious or have suggestions. I'm thinking I need a lower layer height, maybe slower speed or lower extrusion temp.
(the large photo is necessary for the detail)
Re: ABS VS PETG
Posted: Tue Mar 17, 2015 2:53 am
by jimc
pretty sure your under extruding a little. see that pitchfork looking feature to the lower left and right of the red circle....look at the gaps in the curled sections. the extrusions are much thinner in the pet model than the abs.
Re: ABS VS PETG
Posted: Tue Mar 17, 2015 3:19 am
by jereywolf
Thanks JIm! I'll turn up my multiplier and see how that goes first.
Re: ABS VS PETG
Posted: Tue Mar 17, 2015 12:46 pm
by jereywolf
I upped my extrusion multiplier by 10% and lowered my layer height. In the simulator, I could see that it was laying down more layers on the trouble areas, so I though that would be helpful.
It turned out about the same.
Because those little details are so small and it's retracting between every one...could it be that I have too much retract and it's not pushing out enough filament to properly build?
When I thought about it, I checked, the retraction for my ABS prints is set to 1.4mm, and for PETG it was 2.0mm.
Re: ABS VS PETG
Posted: Tue Mar 17, 2015 2:02 pm
by ednisley
jereywolf wrote:turn up my multiplier and see how that goes
Any reason to not calibrate the multiplier, so the width is exactly right? That will, at least, eliminate one variable from the mix.
viewtopic.php?f=3&t=1964
Re: ABS VS PETG
Posted: Tue Mar 17, 2015 3:04 pm
by jereywolf
ednisley wrote:Any reason to not calibrate the multiplier, so the width is exactly right?
I did that though. I had it dead on at 0.4mm.
Re: ABS VS PETG
Posted: Tue Mar 17, 2015 3:32 pm
by ednisley
jereywolf wrote:dead on at 0.4mm.
Because the nozzle produces the thread width that the slicer intends, there's no need to fiddle the Extrusion Multiplier: dial that back and look elsewhere for the problem.
Pushing PETG through a V4, retracting 1 mm @ 60 mm/s with 1 mm minimum distance seems to work fine on my models, so 2 mm may be high. If you make it too
low, you'll see more hairs connecting the features.
The top infill looks sparse, which may be due to speed. I've been running top / bottom infill at 25 mm/s = 1500 mm/min, which gives the PETG enough time to settle down and make friends with its new neighbors.
If S3D offers Hilbert Curve infill, you might like that for the background pattern:
https://en.wikipedia.org/wiki/Hilbert_curve
Send me the STL file and I'll give it a try...
Re: ABS VS PETG
Posted: Wed Mar 18, 2015 7:56 pm
by ednisley
ednisley wrote:Send me the STL file and I'll give it a try
So he did and I did and it came out a little something like this...
The Slic3r preview shows that the dots are about as small as they possibly can be:
That's Hilbert Curve infill to give the background a textured appearance, instead of the usual linear infill stripes.
The circle of dots came out OK, with some PETG hairs blurring their edges:
Some hairs fused adjacent pairs of dots in this row together:
These dots look better:
All the swords and other doodads look great, modulo a few hairs.
Printed in eSun magenta PETG at 250 °C, with 0.2 mm layers, 0.4 mm width, 25/50/75 mm/s speeds, and 1 mm @ 60 mm/s retraction.
I think some retraction fiddling will improve Jerey's results, but at least we now know the M2 can produce those fine details in PETG.
The pix are monochrome, because the full color version resembles a saturated red blob with no detail. The stuff looks like glass in the pictures; it's more translucent in real life.
Re: ABS VS PETG
Posted: Wed Mar 18, 2015 8:54 pm
by Jules
Looks nice! I love that Hilbert Curve infill pattern (which unfortunately got taken out of S3D. Hope they put it back.).
I got S3D to do a nice Crosshatch pattern that looks similar though, if anyone is interested. It does add to the time that it takes to print.
Sorry for the print quality, the bed is moving. (Attempt number 3 on this stupid thing....first was lost to inadequate hairspray and edge curl. Right about at this spot too.) Grrrrrr.
Re: ABS VS PETG
Posted: Thu Mar 19, 2015 2:07 pm
by jereywolf
I ran one more print and it came out great! But rather than adjusting my retraction, which was at 1mm, I changed another setting. I turned off the optimization setting under the layer tab.
With "Print islands sequentially without optimization" checked there was more time for the extruder to get to the next mound.It printed from side to side instead of printing the next mound in line.