Laser Cut Living Hinge and 3d Tenon Joint Kinetic Sculpture

A kinetic sculpture laser cut from 1/4" birch plywood made for Computational Fabrication MAT238

1/4" birch plywood, Fusion, Illustrator, Universal Laser Systems laser cutter

The stand was designed in fusion, first as a smaller prototype, and then later at full scale. I had user parameters set up, so it was easy to modify. However, one of my assembly choices caused some issues, as seen in the third image. Since the piece has symmetrical parts, I just used the side that was still intact after the size change. The hinges went through a few design iterations, one of which is shown in the fourth picture. This pattern with the angled cuts was abandoned for the curved patten in the fifth image. These curved cuts tended to get less cracking failures. The design of the hinge was moved entirely to illustrator so I could apply kerf offset only to the joint and not to the hinge pattern. The hexagonal cut-outs were added to remove weight from the piece.

After getting the laser cutter's settings dialed to cut cleanly through material without singeing and overly drying the material, the kerf was .2 for a snug press fit. The tight parts of the hinge pattern did get darker than the straight cuts, and a few did ignite, causing those hinges to fail. There were a number of hinges that didn't work because of material inconsistencies such as glue spots or knots. I got five nice hinges out of 7 after prototyping. Each hinge took ~15 minutes to cut. The entire stand also took ~15 minutes. With the amount of time I stood by the laser cutter you would think I'd have taken a picture or two...but nope. So these are the final results.

The stand goes together like a little puzzle and the hinge is press fit into the top rail. The movement is shown in the clip below.