Is this stringing or something else?  

  RSS
Andrew
(@andrewld)
Estimable Member

[caption id="attachment_31861" align="alignnone" width="600"]Stringing or not Travel lines but at full extrusion size[/caption]

Hi all

I have been getting this on bigger prints from time to time. Easy to remove with no real detriment to the finished job but I would prefer that it didn't happen. It's not at every layer as you can see and whilst I could tweek the extrusion settings the current print quality is so good I am loathe to alter them if this is simply "one of those things".

It appears at random heights and is clearly a travel path of the hotend but it isn't fine whispy strings I would normally associate with stringing it is full extrusion.

In short is it stringing or is it something else that I can look for a cure for?

Andrew

Posted : 26/05/2020 8:46 am
Neophyl
(@neophyl)
Noble Member

Doesnt look like normal stringing to me.  It looks like the filament hasn't adhered to the layer below it so its just being pulled straight across.  If that was the case then id expect there to be a slight gap in the layer where the filament that was pulled across should have been.

That model looks like it slopes outward so it could be that the overhang is too much and that the perimeter above is not close enough to the outer perimeter of the layer below for it to connect with.

If you could post the .3mf project (zipped up here) then we could take a look and check out the settings and preview the overhang etc.

Posted : 26/05/2020 9:33 am
Andrew
(@andrewld)
Estimable Member

I didn't think it was that because the layers it happened on were on a "foot" before the slope kicks in. Also its not on all faces. The first 2 layers were pristine (pause to feel really chuffed with myself). The "artefacts" appear to start at 3, 5 & 8 then stop....but that could be my eyes.

mf attached. 

Thanks

Andrew

Posted : 26/05/2020 10:49 am
Andrew
(@andrewld)
Estimable Member

I tried to attach the mf file but it said file type not allowed when I posted. Is there another format that would work?

Thanks

Andrew

Posted : 26/05/2020 10:52 am
Andrew
(@andrewld)
Estimable Member

Second shot as zip

Posted : 26/05/2020 10:55 am
Andrew
(@andrewld)
Estimable Member

emoji of me trying to squeeze zip file through SD slot

 

AD

Posted : 26/05/2020 10:57 am
Neophyl
(@neophyl)
Noble Member

That's actually a nicely designed model with good geometry for 3d printing so its not what I initially thought looking at the pictures.  This is why posting the .3mf is so important as it allows a more detailed look.

Had a look at the slice preview.  At layer 5 it starts to do some small areas of solid infill along the perimeters in spots.  It might be this that its dragging along in some areas only (maybe down to the cooling only coming from the front).  I tried various settings to get rid of this extra but the only change that seem to stop it is increasing the perimeters from 2 to 3.  For a functional part like that I would normally have 3 anyway.  It increases the print time slightly by about 15 minutes and does use more material but the part would be much stronger and I think its this small solid infill that's being done that is whats being dragged along.  It certainly matches up to your reported layer height and would also explain why the perimeter doesn't have a gap in it.

Anyway that's what I think is happening.

Posted : 26/05/2020 12:09 pm
Andrew liked
Andrew
(@andrewld)
Estimable Member

@neophyl

Thanks. As noted the finished product is really nice and a wee bit of fine sanding took the tags off. The laugh is that my last spool holder used rollerblade wheels that worked really well but my new prusa filament spools have a much smaller diameter. Once this is done I can get my enclosure put back together happy that I can use any spool. To be honest though I don't understand why my wife doesn't like it on the dining table. 🤣 🤣 🤣 

 

Andrew

Posted : 26/05/2020 1:22 pm
Share:

Please Login or Register