PETg stress/strain test

[Tim]

I was curious as to just how springy PETg is, so I designed this spring clip (see attached zip file with an STL in it), which is supposed to be a filament clip (although I don't think it works particularly well for that purpose; I think the arms of the clip should be about 1/3 the length they are now, and the filament hole needs to be reduced by about 5%). When printed, the clip deforms to its maximum extent under about 12 pounds of force, and readily springs back to its original shape. I'm going to try playing with other variations, see how much force I can get the PETg to generate on a clamp without breaking or deforming.

[Tim]

After a few tests, I settled on this clamp design (attached). It bends to its maximum extent under about 18 pounds force. However, after a number of flexing cycles, it does not return completely to its initial state. Still, it does not appear to be weakening, and it has an impressively strong grip.

By the way, I printed this in Simplify3D using manual supports at 2mm resolution, and never had any issues with the printing.

[jsc]

What's the intended use for the clip?

[Tim]

I advertise it as a filament spool clip, and it works reasonably well as such, although mostly I was just interested in the geometry of that kind of clamp and whether or not the PETg would be able to take that much force without breaking or deforming.