Strange under extrusion please help

(Daniel DeRuiter) #1

Thank you in advance. Using an Ender 3 with octoprint and Cura 3.6.0. Not sure if I have a hardware or software issue, but I get under extrusion at holes or cutouts as you can see by the photo. Using PLA with a 0.5mm nozzle and EZR extruder add on. No slipping of the bowden tube I can detect. As you can see from the photo it ALWAYS occurs at a hole or slot???

(anon57870006) #2

Does it happen at the same Z level if printing another narrower object? If yes then Z system makes a sudden jump at that level.

(Daniel DeRuiter) #3

Thank you, I’ll have to look out for that. Just noticed it makes the part very weak around holes and cut outs.

(anon57870006) #4

@deruida for strong parts I recommend using PETG and keep PLA for art printing

(Daniel DeRuiter) #5

Thank you for the tip. I am new to the 3d printing world. And I guess you can teach an old engineer new tricks!

1 Like
(Michael K Johnson) #6

@deruida The picture just doesn’t have enough resolution for me to tell what’s really happening. It isn’t obvious that it’s actually under-extrusion. You could have under- or over-retraction, for example, or mechanical slop (loose belts, insufficient preload on wheels, etc). You could try to reduce Y acceleration and/or Y jerk settings and see if that changes it at all; if it’s a difference in bed movement that can make a difference. I run much lower Y accel/jerk than X on my “bed flinger” printer.

I have used PETG for some very durable parts, though it tends to be more “stringy”. I’ve used esun’s PLA+/PLApro when I’m looking for a middle ground that is tougher than PLA but less stringy than PETG, including some cases.

(anon57870006) #7

PETG does make troubles with 0.4 nozzle. Almost none with 0.6 nozzle and none at all wit 0.8 nozzle, so mechanical parts without art I do with 0.8.
The 700mm Dragon in my album is 0.4 nozzle, the woman torso too.

My Albums

1 Like
(anon57870006) #8

Actually for better vision of the problem indeed to make a high resolution album of the printer and its corners, especially that no one of us has experience with all. Please see QuadRap Detailing in my album as an example.