Ultimaker 3 PVA wall problem?

[JelloAxel 0]

Hello

 

Is there a way that i can get rid of these holes in the part`? I think in some way that PVA material gets between the PLA layers under printing. Maybe its going too fast? 

 

PLA 0.12mm 50mm/s 200°C

PVA 0.12mm 25mm/s 220 °C

[gr5 2,170]

How important is it to get rid of them?  The solutions I know will make the print take much longer to print.

 

Do you care about how it looks or does it have to be water tight?

 

For both:

 

It appears they are happening at the z seam.  These problems tend to occur at speed changes (in this case it stops and moves to the inner portion of your part or maybe this is the start of a layer).  So you can reduce the speed change by printing slower.  Much slower.  Try 25mm/sec for ALL printing speeds (infill, shell, etc - I think there are 7 printing speeds). 

 

Also keep other (non printing) speeds fast (travel speed, retraction speed) so there isn't time for the nozzle to leak (and then start up with less than ideal nozzle pressure).

 

Also make sure your wall thickness is a multiple of your line width - if line width is 0.37mm then wall thickness should be 1.11 or 1.48 (I prefer line width of 0.4 but 0.37 works fine).

 

For water tight:

 

Increase the line width to nozzle+20% so for a 0.4mm nozzle, try 0.5mm line width.  And again, make all the printing speeds the same (40mm/sec should be slow enough).  Make sure your wall thickness is a multiple of your line width.  So if line width is 0.5 then wall thickness should be 1.0 or 1.5 (1.5 probably better for water tight).

 

You can even go as high as 1mm line width but if you do drop the speed by about 2X.