Print Strength Test Rig

This is a small rig I designed to test filaments for usability to print enclosures.

It's used to test how hard it is to break the print along the layers.

Print the bar vertically with 100 % infill and not only perimeters but at least one line of diagonal infill for more rigidity. Use a brim of 10 lines or so. Should take only around 10 minutes to print.

Then insert it into the rig as shown on the first photo, slightly fastening it with the screw. Measure with a caliper how far the screw head sticks out from the frame, should be about 22,5 mm.

Slowly tighten the screw until the bar breaks, hold the screw in place and measure again.

The difference is the result. The higher the number, the sturdier the layer adhesion is.

Best result so far, with non-flexible filament: all the way in (22,5 mm) and not broken, just cracked: PETG at 240 °C nozzle temperature. See second photo.

At the wrong temperatures / cooling settings it breaks as early as 3 mm in.

Last photo: PP