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Joined 3 years ago
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Cake day: July 4th, 2023

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  • Hard to tell, most of it looks fairly good except a few spots here and there.

    That could be grease on the print bed, maybe time to give it a wash? When PETG goes wrong for me, it’s this 90% of the time.

    I use hot water and a little detergent with a lot of rinsing. Use gloves because even clean hands leave oils behind.

    With PETG it’s hard to get the first layer right but if it’s good the rest of the print generally goes fine.

    Molten PETG is very sticky and if you get a bit stuck to the nozzle it can build up, get worse and suddenly take out a bunch of nearby lines leading to gaps in the layer like this.

    To counter this PETG first layer should be:

    • Printed very slow e.g. 20mm/s
    • At a higher Z offset than PLA, the plastic should flow out the nozzle and fall onto the bed rather than be squished flat.
    • High bed temperature 80C / 176F
    • Zero or very low fan speed for the first couple of layers

    If you can see marks left by the nozzle it’s too low. The lines should have a rounded look.

    It could also be wet filament, does it make popping sounds when printing?


  • I was a bit of a deadbeat, I had a reasonably ok job but I was living in a tiny flat and spent most of the money I earned on drink and drugs, didn’t have a steady GF. I was into all sorts of extreme sports then and that led to a pretty serious biking accident requiring multiple trips to hospital. Was very lucky it wasn’t fatal.

    It was 2008 and that was the turning point.

    Maybe due my brush with death? I started to turn my life around. I stopped smoking. Changed my scenery. Quit my dead end job after finding better one. Moved from the city to the countryside to be with my girlfrend then got married.

    It’s hard to think all of that would have happend if that tree hadn’t been growing in that particular spot for me to crash into. Things could have gone very differently.










  • This seems strangely just a little bit wrong.

    As mentioned there’s no units on STL files so the slicer assumes millimeters but warns you if it thinks the scaling is obviously not right.

    My blender units are meters.

    If I just export the default cube from blender (which is 2x2x2) and load it up in the slicer I get a prompt saying the units seem to defined in inches. It’s assuming I can’t possibly want to print a 2mm wide cube. Do I want to convert it to inches?

    If I answer No, I get a perfect 2mm cube, good luck printing that. If I choose Yes, to convert it then I get a cube 50.8mm across. (2x 25.4mm) exactly 2 inches as expected.

    Going back to blender, deleteing the default cube and creating another cube but scaled to 0.1m. This time exporting to STL on the export save dialog there is a scale setting: set this to 1000 (to convert from blender 1m units to Prusa 0.001m units). Now the STL is imported into the slicer with no fuss and is exactly a 100mm cube.

    It seems I can’t recreate your problem.