Gaps in print between main body and walls

[JessJ 0]

Hi all. I'm sure I'm missing something basic here and I've tried playing with settings as described on various troubleshooting guides but I'm at a loss so I've come here x

 

I seem to have a gap between walls and the main body of the print. I first assumed it to be not enough top layers but this is 90% gyroid infill and 12 top layers. Holding the print up to the light shows that there only seems to be a bottom layer where the gaps are. I'm sure I am missing a setting, I just can't work out out what it is.

 

I've reset the profile to default and put the temp up in case that was a problem it's helped a bit but not by much..

[GregValiant 1,342]

It's hard to tell with the photo.  Could you have some under-extrusion going on?  What printer?

With your model loaded in Cura and the settings the way you want, use "File | Save Project" and post the 3mf file here.  I've got some scraps of PLA left and I can use some up on a test print.

But the initial view (from maybe a couple thousand miles away) is that it looks like under-extrusion.  90% infill should be near solid.

[JessJ 0]

Hi thanks for getting back to me x

It does seem under-extruded but that only appears where there are details around where walls meet the main body. Other prints seem fine and it will happily print a tall model without the any sort of layer gaps etc.

The printer is a wanhao duplicator i3 plus x

WDI3P_binderpin.3mf

[obewan 37]

wanhao duplicator i3 plus x.   is this a bowden feed or a direct drive extruder ?

 

[GregValiant 1,342]

I opened the 3mf file and generated a g-code file (without making any changes) and printed it on my Ender3Pro.  Looks good to me.

I'm going to stick with the under-extrusion thing.  It can't hurt to double-check the actual filament diameter and make sure that's the filament diameter in Cura, and to also double-check your E-step calibration.  My print came out looking just like the Cura preview even with the poor filament I used.

 

The mark in the top right of this photo is from the Wipe-Out move in your End Gcode.

 

[GregValiant 1,342]

Retraction was at 6.5 in the 3mf file so I would guess it's a bowden.  If it's DD then that would be way too much.

[JessJ 0]

Ooh you might be on to something there. It's direct drive.. I'll a lower retraction... maybe half?

[GregValiant 1,342]

Start at 1mm and see how it goes.  That's a pretty small part so I think I'd test on a calibration cube or a benchy first so there would be more retractions.

 

You might want to clean out your hot end as well.  If you were pulling hot material back that far you might have a plug above the heat zone.

Edited July 27, 2021 by GregValiant

[JessJ 0]

Tested it on the small part with 1mm and it seems better but still has holes but closed up considerably, going to try a larger print alongside the small part

[JessJ 0]

Hmm it seems that the retraction didn't fix it after all, the print looks a little better but theres still a lot of gaps

[GregValiant 1,342]

You are confident in your E-step calibration?

When you unhide all the settings in Cura - all the Flow numbers are 100%?

I'm still a little leery about the effect of the 6.5mm retraction on a direct drive.  It can act like heat creep because soft plastic gets drawn upward where it doesn't belong, cools a bit, and can cause excess friction and under-extrusion.

If you warm up the hot end and pull off the nozzle you can shove a 300mm long piece of filament down through the hot end (don't use the extruder just shove the filament through quickly by hand).  If there is a plug of plastic in the warm hot end the filament should push it out.

[obewan 37]

as well as having 6.5 retraction, you also have 0 retraction extra prime.

On my direct drive system i use 0.7 retract and 0.2 extra prime.

The extra prime help overcome any ooze during travels

[JessJ 0]

Completely disassembled the extruder and hotend today new nozzle and new piece of bowden and which didn't fix it. I'm not sure how to do the esteps on this machine I'm going to have to research into that thanks for thr help so far 🙂

[JessJ 0]

6 hours ago, obewan said:

as well as having 6.5 retraction, you also have 0 retraction extra prime.

On my direct drive system i use 0.7 retract and 0.2 extra prime.

The extra prime help overcome any ooze during travels

I'll give that a go next! Thank you 🙂

[GregValiant 1,342]

This is a little Windows app I wrote for leveling and printing from your computer instead of having to use the LCD.  It also has a built-in E-step calculator and shows printer responses to commands.  It prints from the SD card rather than sending gcode over the USB port but does require a USB connection.  There is a readme file and the total program consists of two dialog boxes.  It really isn't very complicated and most folks seem to be able to muddle through.

It's an unsigned app so if you are inclined to install it you will likely need to get it past your anti-virus.  The installer will put a shortcut on your desktop and there is an un-installer.

 

 

Greg's SD Print Tool.zip

Edited July 19, 2022 by GregValiant
Update Zip File

[1-prop-head 1]

Been working with Cura since I got my Ultimaker 2 in 2006 and just had this issue:

 

Cura 4.10 leaving gaps between infill and outer wall.

 

It appears to be with this release of Cura.  

In addition Cura is not responsive on a mac running Big Sir after returning from sleep mode. Need to close Cura window and restart to get it back.

 

This is a photo showing the infill gap:

The object was drawn using OpenSCAD and Cura is operated on a Mac Mini with Big Sur.

No changes were made to printer firmware.

 

Ultimaker 2 updated to 2+

Filament = ABS

Nozzle = 0.4mm

Temp 238C

Infill 50%

Wall Thickness 1.2mm