Wall distance issue with flex filament

[fjallbacka 0]

I want to know if there's a setting for extruding the walls more close to each other. I attach a picture of my problem, I have a slight under extrusion (I increased the flow and decreased speed, now I'm printing another test) but the most notable problem here is that the wall lines are not so close to each other and they aren't fusing together. When applying a little force, they get separated. 

[gr5 2,267]

The problem is underextrusion.

 

What kind of printer did you use?

 

If it's a bowden printer like an Ultimaker you need to oil the filament.  Put a drop of oil on the filament before inserting it.  The oil will not affect the print in any way.  Really.  Add another drop every meter or so.

 

You many need to slow the print further.  Maybe down to 10mm/sec.  

 

These 2 things - oil and speed are probably enough.

 

You may need to increase the temp as high as 240C.  It depends on which filament you are using exactly.

 

[fjallbacka 0]

I'm using an Ender 3, and the filament is a new national filament (which is supposed to be printed with the same settings as PLA, because it's not a filament that much flexible). I will try oiling it, the settings I'm currently using are:

- temp: 220C

- speed: 50mm/s

- flow: 110%

- retraction enabled, 5mm @ 25mm/s

I know that these settings aren't for most flexible filaments, but as I'm telling you this is a "new" "experimental" filament type. Supposed to be just as easy to print as PLA (and so far, aside that inconvenience, the prints are flawless, I attach a side/bottom view of the print)

 

I'm currently printing another with these new settings (and I included the oiler):

- temp: 220C

- speed: 40mm/s

- flow: 115%

- retraction enabled, 6mm @ 25mm/s

I'll let you know what happens. 

Edited May 31, 2019 by fjallbacka

[fjallbacka 0]

Better on the under extrusion side, but still getting adhesion problems on the walls. Isn't there something that I could tweak so that the wall lines are closer to each other?

 

The old one is the one on the right (of course xd)

Edited May 31, 2019 by fjallbacka

[Juskuboy 1]

The part is very little. Try change fill parameter towards 100% (remember make g-code after that)  It takes more time and more filament but usually

I got better result. (next round of printing comes near and the clue is better)

[gr5 2,267]

If wall isn't attaching it's still underextruding somewhat.

 

I have a lot of thoughts.

1) Pay attention to if it prints outermost wall first or last.  You probably want "last" which is I think default in most profiles.

2) You can play with line width.  I think it defaults to 0.4 for most 0.4mm nozzle profiles but you can set it to 0.35 for example and it will print the lines .35mm apart instead of .4mm apart but will underextrude correspondingly.  Then you can increase flow by 0.4/0.3 or 14% (flow at 114%) and you will be extruding .4mm lines .35mm apart.  Not recommended but will work.  You may get too much overextrusion in most places.

3) Keep slowing it down.

4) You say 40mm/sec and 50mm/sec in posts above but are *all* speeds the same?  Typically the outer and inner shells are printed at a different speed than the infill.  Try to make *all* the printing speeds the same (leave travel speed fast, leave first layer slow)

5) Ender has a TUNE menu where you can set the feedrate to 50% to see if that helps - you can experiment with temperature, flow and feedrate on each layer and keep notes and realize what speed and temp is best to get zero underextrusion.

6) Everyone thinks the oil will mess something up.  It won't.  Try it.  It works wonders at least on bowden printers.  Not sure if your ender is a bowden printer.

 

7) Normally going over 110% is a really bad idea - at least for PLA  - but for these flexible filaments it might be okay.  At some point if you have the flow too high it will bunch up and tangle all up inside the feeder.

 

#8 - Cheetah is also considered an "easy to print" flexible filament.  Because it's stiffer than ninjaflex.  These are still not as easy as PLA.

[fjallbacka 0]

@Juskuboy I don't want 100% infill bc the part would be really stiff. I need it to be more flexible.

 

@gr5 I'll start answering in your questions in order:

1) The outermost wall is the last one.

2) I'm currently trying that. Everything was left the same apart from line width (which was 0.5mm to 0.4mm). This size might seem odd, but I'm using creawesome mod (https://github.com/trouch/CreawsomeMod) and indeed my PLA prints got much better (in expenses of more printing time, I used to print at 60mm/s. Now I do it at 50mm/s).

3) I will.

4) Those speeds change, 40mm/s is just for infill. Everything else is about half (Except for travel movements of course).

5) Yup, I might do that as well if this settings I'm currently trying fails.

6) I've already put the oiler (I've already printed it before but never used bc wasn't necessary for PLA). The Ender 3 is a Bowden printer.

7) Yes, I might need to keep an eye during printing.

 

Thanks for your help! It is much appreciated.

[giostark 0]

Hi,

Absolutely I didnt want point far what the good gr5 say , but I would like report my experience.

I had similar problems.

I manage in 3 way depending on  different parts.

1)as suggested , in the menu "quality" try to rise the wall width. But this can generate some trouble in the slicing.

In an old post on github I found that Cura remodel all the slicing when you touch the width of the wall or of the infill. So eventually you can go in other troubles.

2)I manage to use just one wall and then concentric infill (you can't manage the overlap here)  to simulate walls. Or use infill "lines" and control the overlap with walls.

3) Play with the general flaw. Tray to rise it also 15/20% for see if it can sane the situation.

 

In general I have noticed that Cura some time have difficult to slice some 3d stl. I use FreeCAD and when the wall or the piece is not exactly a multiple of the nozzle you need to work on the settings for fit a perfect slicing.

Ex. (with a 0.6 nozzle) For print a wall of 2.2cm I had to set standard wall width as 6.6 and top/bottom line width as 0.4. I know that it have no sense , but it was the only permutation that result in a good print and in a good slicing preview.

 

Good luck!