Print error - stringy holes

Hi all, having an issue with “stringy” and incomplete prints. The attached image will explain. Print settings are for high detail and I’m using the basic PLA, maybe I need a better material? Thanks.

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Here could be a lot of solutions.
It seems that just the first layer is stringing at the holes,- right?

This means your bed calibration is not good enough for your print settings.
I would suggest you to slower your 1st layer speed,- make a custom profile and ride the first layer at 12mm/s instead of 18mm/s. Maybe give the material a bit more heat (+5°C).

The easiest way to figure problems out is to watch the print when your issue happens.- Then you would see, aahhh, bed adhesion.

Such problems could also cause:

  • print or bed temperature is too low
  • print speed is too fast

Right picture, hole near the hole:

I see there is a kind of under extrusion, i would recommened you to improve your linear advance (also called K-factor), see in this post :slight_smile:Improving Print Quality - #13 by C.Harris

Hope this helps!

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I have experienced issues printing concentric circles before as well. Check the sliced file you may see that because you are trying to print a smaller circle within a larger one, that if you have too few walls, your machine ends up trying to print the walls of the smaller circle in mid-air with no or minimal support.

If this is the case you can simply increase your number of walls/shells or re-orient the part so that the circles are not parallel to the build plate.

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Yes, there is a hole within a hole. Basically there is a hole for a screw to pass through and around that hole is a wider recessed area for the screw head to sit flush. The wider recessed area is only 1mm deep. So I think you are saying there may not be enough slices within that 1mm? And to increase the resolution.

Not the resolution as that would be layer height, instead you need more walls in that area.

I assume you are printing with a 0.4mm nozzle with 2 shells, this will result in a wall thickness of 0.8mm, but as you said your print has a recessed area around the hole which I assume has a larger radius than the hole by more than 0.8mm? If so your printer will end up printing the circles that make the walls of the hole in mid air after printing the walls of the recessed area.

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