This model is a useful byproduct of the research I did for my Prêt à Faire: Printable Readymade Models series, inspired by the works of the artist Marcel Duchamp.

After several failed attempts at creating a print-in-place piano hinge for one of the works, I concluded there was no reliable way to achieve that goal, so I pivoted to creating individual parts that could be assembled. Here it is!

This model is the smallest working hinge I could reliably prototype in a variety of materials without breaking. Interestingly, taken by themselves, the pieces are a bit fragile. But once assembled, the unit becomes surprisingly strong.

PRINTING

For the PLA prototype seen in the images, I printed solid using a 0.2 mm Structural setting on an MK4, with organic supports on the build plate only. This allows the holes to remain open without filling up with unremovable support material. It does NOT need a raft, despite the warning you may get in the slicer.

The round axle has a small divot carved out to lay flat on the build plate, and I never had issues with low adhesion from the start. 

AXLE ALTERNATIVES

The axle hole is sized so that one can use a piece of unprinted filament instead of a printed axle. However, I found it challenging to find filament off the roll that did not have curvature memory, which causes the hinge to warp. The printed hinge removes that problem. Nevertheless, you have the freedom to choose a printed or non-printed filament (1.75 mm) axle.

ASSEMBLY

You'll be shocked at how easily the axle glides into the holes! At least in my experience, I did not have to do any cleanout or prep. My only advice here is to go a bit slow, don't try to force the axle, and push it in a centimeter or two at a time rather than attempting to ram it in with one go.

CAN IT SCALE?

This model scales up well. I strongly discourage anyone from scaling it down.

A non-uniform scale-up along the long dimension can (theoretically) create a longer hinge, but I have not tested this. I wouldn't recommend a non-uniform scale-down for a shorter hinge. Instead, I would recommend the Cut feature in the slicer for that.

Making wider flanges: in a modeling program, you can extrude the long vertical face of the flange to increase its width, or Boolean combine a rectangle of the same height and length. Just make sure nothing interferes with the angled face adjacent to the round element, which is required for rotation clearance. If requested, I'll add an alternate with a wider flange.

CHANGE LOG

Watch this space…