PETG 1st Layer Problems - many small parts

Bambu Lab P1 Series
1

I have had my P1S for a few weeks and generally getting on well. However, I have consistently found issues when trying to print lots of small parts in petg. The first layer would commonly fail for some parts while most would be fine. The location on the bed would vary.

I tried adjusting temp/fan/retraction settings etc but these did not resolve the issue. In the end I have landed on slowing down the first layer to 25mm/s for anything with separate parts or a complex geometry and this seems to have made a massive difference.

Simple, larger objects seem fine at the default of 50mm/s.

Is this something others see or am I missing something else which could be the real culprit?

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3

Small prints have a small interface with the build plate, so it is quite natural that they can more easily be dislodged.

You can maximize 1st layer adhesion by

  • using a thoroughly cleaned bed (soap and water),
  • going nice and slow on this layer as you have done,
  • use a textured PEI or a smooth plate with glue (apply glue stick and distribute evenly and thinly with a wet cloth or use a liquid glue stick)
  • use a brim (may need to reduce the brim gap for really troubling parts)
  • increase bed temp by 5° for the first layer only
  • increase nozzle temp by 5-10° for the first layer only (caution: only when using glue as a release agent as it may stick too well to the build plate)

:crossed_fingers: and hope this helps!