Overhangs with sharp corners

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MTVDNA
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Joined: August 7th, 2016, 10:29 pm
Location: Netherlands
3D Printer(s): Ultimaker 2

Overhangs with sharp corners

Post by MTVDNA »

Hey guys,

I'm having some trouble when I try to print stuff with overhangs that have sharp corners or small edges in general. They tend to curl up a lot, making the overhangs look pretty bad. Longer edges print just fine. For example I tried to print this christmas tree.
IMG_20161223_221223.jpg
If you zoom in you can see the under side looks very blobby.

I've tried no fans, full fans, a bunch in between, but nothing seems to help.

I sliced it with Cura 2.3.1 using the Spiralize Outer Contour setting (vase mode), printed with PLA at 210 °C and a 0.8mm nozzle.

What's the trick?
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Izzy
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Location: England
3D Printer(s): Ultimaker 2

Re: Overhangs with sharp corners

Post by Izzy »

I would do a sacrificial test of a model and try dropping the temperature 4'C every 5mm height and see if one gives a better result, you may need to reduce the print speed too.
MTVDNA
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Posts: 138
Joined: August 7th, 2016, 10:29 pm
Location: Netherlands
3D Printer(s): Ultimaker 2

Re: Overhangs with sharp corners

Post by MTVDNA »

I dropped the temp in steps of 5 °C and eventually settled on 185 °C. I don't really dare dropping it any lower. The corners still curl up a little bit, but it's much much better than before.
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antiklesys
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Re: Overhangs with sharp corners

Post by antiklesys »

I'm working with some plastic which extrudes well at 170°C. Perhaps you can go a little lower than 185° depending on your PLA properties
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