How to fix, is this Stringing?

[Doug68]

I get this effect on parts with a concave side:

[img]https://lh3.googleusercontent.com/DDg7q ... no-tmp.jpg[/img]

This is with PLA running at 210c, as HE280, a 1mm retract at 25mm/s, z lift 1mm. Extrusion multiplier 1.

Any Ideas on how to reduce this?

Towards the middle of the part is where its starting the perimeter runs at that point there's a small bump on the top layer and the stringing follows out from this point also. From a practical point of view most of the time the concave side of the part is not important to me, but I'd like to get this cleaned up if I can.

[thingismith]

Not getting the pic...do they look like branches or columns? Try upping your nonprint movement speed.

[Doug68]

I think I fixed the picture (Google photos) let me know if you cant see it still.
Here's the URL if no picture above: https://goo.gl/photos/YAaJymvZJnVT6XTs8
Cheers.

[Mac The Knife]

You fixed the picture,,, and yes, that's stringing.

[Juicy]

https://www.simplify3d.com/support/prin ... ch-plastic

This is a guide I have used for tuning. It has to do with your retraction settings.

[Doug68]

To cut a long story short the retracts on my machine had become inafective due to slop in the bowden tube fittings, a cable tie as per the pic below fixed that.
Also after a few months of running nearly 24 - 7 I found nearly all the screws holding the machine together were lose.
And the spring apears to have gone soft on the extruder so that was slipping too easily.

[img]https://lh3.googleusercontent.com/76avh ... no-tmp.jpg[/img]

[knabo]

I will just add my situation to this thread, since it is relevant.

I finally got my V2 to V3 conversion printing decent walls and now it is on to retraction tuning.
References for this test are :

https://www.matterhackers.com/articles/ ... -to-oozing
https://www.simplify3d.com/support/prin ... eshooting/
http://www.sublimelayers.com/2016/10/so ... racts.html
And numerous posts on the subject

My current setting are:

Standard yellow PLA
190C hot end temp
300mm/s non-printing movement speed
and:

These are my results:

Where do I go from here?

[Juicy]

Where do I go from here?

From what I have read on this subject, and am going through as well; a lot of stringing is a result of a jam in the hotend. Are you sure your bowden tube is seated all the way? Heat the hotend up to 100C then pull the tube out and if you have a "hockey puck" of filament directly under the tube, you have found your problem. I believe that you should have no more than 2mm length on move for your retraction setting. Is your EZRstruder grinding filament?

[knabo]

The Bowden tube is seated and the tube locks are installed. I am using a bondtech extruder, it is not clicking or grinding.

My prints are pretty uniform, nothing that would indicate there is a jamming problem.

[geneb]

Stringing isn't a symptom of a jammed hot end.

Stringing can happen when your printing temp is a bit high for the speed you're printing at. When I first work with a material in S3D, I set up similar basics to what you've got, but also add in a 4mm Z lift on retract. I then print a pair of 20mm cylinders to tune the temp to get it to stop stringing.

g.