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Overhang Test Generator: Find Your Printer's Steepest Overhang

Pick an angle range and a step, and the generator builds a row of fins on a back wall, each one steeper than the last, with its angle raised on the base. Print it with supports off: the first fin whose underside droops, curls or turns stringy is past your limit, so use the last clean angle as your support threshold.

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How to find your overhang limit

  1. 1

    Pick the angles

    Start with 20 to 80 degrees in steps of 10. Once you know the rough limit, make a second test around it in steps of 5 or less.

  2. 2

    Size the fins

    Longer fins show droop more clearly. A thin tip shows curling sooner. Keep the labels on so you can read each angle off the print.

  3. 3

    Print without support

    Turn supports off and print with your usual layer height, speed, temperature and fan, so the test shows what your real prints will do.

  4. 4

    Read the fins

    Look under each fin. The last one with a clean underside is your limit. Set the slicer to add support only beyond that angle.

How to read an overhang fin

Turn the print over and look at the underside of each fin, then at its tip edge. The table under the preview lists each fin's angle both ways.

CleanSmooth, flat underside and a straight tip edge, the same as the shallow fins. The printer handles this angle without support.
Slight droopLines sag a little or look rough underneath, but the shape holds. Fine for hidden faces; add more cooling for visible ones.
CurlingThe tip edge lifts up and the nozzle may hit it. Usually too little cooling or too hot: raise the fan or lower the temperature.
FailedLoose, stringy or missing lines. The angle is past the limit: use support, or turn the part so this face is less steep.
Angle in the slicerCura measures from vertical like this test. PrusaSlicer, OrcaSlicer and Bambu Studio measure from the bed: use 90 minus the number on the fin.

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Overhang test FAQ

A small print with overhangs that get steeper step by step, each marked with its angle. You print it without support and look at where the underside starts to droop or curl. That angle is the limit of your printer, filament and cooling.
From vertical: 0 degrees is a straight wall and 90 degrees is a flat ceiling. The table under the preview also shows each angle measured from the bed (90 minus the number), which is how some slicers set the support threshold.
Many printers print about 45 degrees from vertical cleanly, and with good cooling often more. It depends on the printer, the filament, the layer height and the fan, which is why you print this test with your own settings.
More part cooling, a slightly lower temperature, slower outer walls and thinner layers all help. Change one thing at a time and print the test again to see the difference.
Start with 20 to 80 degrees in steps of 10. When you see where it fails, make a second test across that range in steps of 5 or less to find the exact limit.
Set the support overhang angle (or threshold) to the last clean fin. If your slicer measures from the bed, use the "From the bed" column in the table instead.
No. The model is built in your browser and downloaded straight to your device. It is free, with no signup and no upload.

The STL holds the exact angles in the table. Every printer and filament is different, so treat the expectations in the table as a rough guide and trust what your own print shows.