Gaps between walls in one oreintation

[Link 34]

@smartavionics hoping you can help here again ?

 

this model, if printed in this orientation prints with the inner walls are not bonded together and have a small gap just along the area highlighted here

 

The area shown is just 4 line widths wide

 

 

 

on this horizontal area the two inner walls don't bond together leave a small gap, however if I rotate the whole model by 90 deg the gaps is gone and interestingly I don't get a gap on the other parts which are now in the horizontal plane. I have tried the obvious things, up the temp, reduce fan (as I thought it might be the fan orientation), also increased the wall over lap percentage to 25%, nothing made any difference, apart from rotating the model by 90 deg and then everything is fine !. I cant work out what might be happening, I know you are an expert with this stuff, so hopefully have some ideas. I haven't don't anything with the compensate all overlaps which I think you said wasn't working well, but for now I left that alone as it sounds like it should help ?. 

 

Its a odd one, as simply rotating the part fixes it.

 

Many thanks !

 

 

Edited September 19, 2018 by Link

[burtoogle 513]

Hi, @Link, could you please attach the project file (.3mf) or at least the model (.stl) so I can take a look. Thanks.

[Link 34]

Shelf Bracket.stl

[Link 34]

thanks !, just tried wall compensation disabled and it didn't make any difference, I am printing with a 0.6 nozzle, 0.35 layer hight. 0.6 line width. 

[Link 34]

the two parts just rotated by 90

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UM2_Shelf Bracket.3mf

 

this is in the orientation which has the problem. 

 

Thanks again

[burtoogle 513]

Sorry, I don't have an answer but one thing I have noticed is that UM advocate using nozzle sizes that are equal or even larger than the line widths specified in the slicer. Perhaps that works for UM nozzles but it is completely the opposite to what I do myself on my non-UM machines that have e3d v6 hotends. So, if you have a 0.4mm nozzle for your printer, please try the same print, using 0.6mm line widths and see what happens. I print 0.6mm wide lines using a 0.4mm nozzle often with no problems.

[Link 34]

Thanks for looking, I can’t work it out, I designed a test peice, a simple cross symbol with the same dimensions and all the legs print fine, no gaps, so it’s not a mechanical issue, I checked all the belts etc and gave them a tightness tweak for good measure. I also tried printing two of the problematic model at the same time, one in the default orientation and one at 90 decrease, in this scenario they are both fine !, so I thought maybe it’s due to the retraction from traversing between models somehow reduces the inderextrusion after layer change, so I enabled retract at layer change, and that didn’t fix it !. I have no idea, in one orientation on just that model it seems to under extrude right after the layer change. Print another model or rotate through 90 deg or print two models then it’s fine ?.