Thin Wall Printing

[mikee5403 0]

Hi all, i have an Ender 3 Pro with direct extruder mod. I have this issue on my prints when doing thin walls for rc planes any idea what could be causing it?

[GregValiant 1,243]

With the file loaded and Cura ready to slice use the File | Save Project command and post the 3mf file here.

How has the machine been printing?  You have the retraction dialed in and the E-steps calibrated?

[mikee5403 0]

19 minutes ago, GregValiant said:

With the file loaded and Cura ready to slice use the File | Save Project command and post the 3mf file here.

How has the machine been printing?  You have the retraction dialed in and the E-steps calibrated?

 

Hi @GregValiant thanks for the reply. I do have everything dialed in yes. I did change the small length of bowden tube and the thermal barrel to higher end parts the other day as i was having major issues and turns out the bowden tube had broken inside my old thermal barrel. so once changed i re-calibrated everything. It prints ok apart from that go awful..... "snot" if u like lol. I also have a dual geared extruder too.

 

Anyway heres the file u asked for.

CE3PRO_cessna_152_fuselage_2.3mf

[GregValiant 1,243]

Your print temperature of 230 sticks out.  The material is listed as PLA and I would expect 200 to 210.  If it is PLA then it's really loose at 230 and just wants to run out of the nozzle like water.  That's a real problem with all the travel moves you have there.  I looked at it with a couple of different combing settings and there isn't much difference.  Lots of travel = lots of oozing + lots of heat = lots of boogers.

 

Again, if it is PLA you might want to also consider turning on the layer cooling fan.  Unless you already know that you don't want it on - consider 35% at least and you might want to go to 100%.  You want the plastic to harden fast so it stays where it was put and printing at 230° - that isn't easy with the fan off.

 

Single wall models with lots of long travel moves are tough.  There is going to be some oozing even if you were to print at 200°C as it's just the nature of the process.  The means a new extrusion after a long travel can start out dry until the pressure comes up in the nozzle.  With more walls that defect gets hidden.  With a single wall it looks crappy and can seriously impact the structural integrity of the print.  You might want to consider using "Retraction Extra Prime Amount" at about .15mm (EDIT .40) which would equate to about 5mm of extrusion.

 

Mostly though I think you're printing too hot.  I've printed RC boat hulls on my Ender 3 Pro and they turned out pretty well at .4 line width and printed at 205° (and the bed at 50).  They were a lot stronger at .6 line width but a boat isn't as sensitive to weight as a plane.

 

 

Edited June 6, 2022 by GregValiant