Continuing my self-examination for assumptions that might be holding me back, I started thinking about the fact that all the fixtures I've built so far for the box exercise are external to the box. This seemed like an obvious approach - tools are almost always outside of the object that the tools are working on.

But while working with various fixtures, I've occasionally wished for something inside the box to brace against. At various points I thought about building an internal component to mate against the external fixture, but for one reason or another that hasn't happened. So let's try that now.

Internal Fixture

 

It turned out far more successfully than I had expected. When the fixture is on the outside of the box, my hands performing assembly had to work inside the tight internal volume. But when the fixture sits inside, my hands have far more freedom to move around outside and everything is easier to do. The assembly of a test box with this fixture was far smoother than any of the test box assemblies built with previous fixtures.

Since it worked so well, I went digging into the pile of scrap acrylic and cut panels for more boxes. While putting together these boxes by hand, I thought about how I'd automate the various tasks involved. The good news is that the fixture is no longer the biggest blocker, other aspects of box assembly now demand some problem-solving time.

Task #1: Peeling the protective paper backing off the laser-cut pieces of acrylic. At the moment this is a very tedious task that demands strong fingernails and luck. If we want to make a production line of a laser-cut acrylic product, we need a solution.

Task #2: Dispensing Weld-On 16 acrylic cement. Acrylic cements like Weld-On 4, with low viscosity and flows like water, have been outlawed by the South Coast Air Quality Management District government agency. So any dream of production will have to figure out how to work with the legal but far more viscous Weld-On 16. Applying by hand resulted in inconsistent beads of cement and aesthetically ugly joints.