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Make Something Big

Week 5

"Make something big". That's the entirety of the brief, with the expectation that we use the Shopbot, a 2.5d CNC machine, or the water jet machine. Having played with both in the past and being low on time this week, I decided to use the much more predictable Shopbot to play around.

I wanted to make something that worked at many sizes, but really became fun at larger sizes. Unlike furniture, this piece doesn't really have a whole lot of utility on its own but seeing an iris diaphragm at this scale is a treat.

They're most commonly used to control light coming into a camera but you've probably seen them in video games, at Burning Man, and pretty much everywhere. It's because they look totally sweet.

After kicking around a lot of design ideas and playing around with OSB material, I slowly realized that without any substantial flex in the material, it would be hard to do some of the more clever, space-saving iris designs which have the individual petals overlapping each other.

I sucked it up, created a less space-efficient design that still overall had a decent-sized center hole and started cutting with the Shopbot. I was surprised how fast everything went. Everyone had been warning me that the machine was really slow and meticulous but when doing exclusively profile cuts on this low-end material, the full cut took around 5 minutes.

I'd initially spec'ed out using 3/8" bolts to hold everything together and act as rotation points, but after cutting, it seemed that I'd designed the holes to be waaay too tight. The screws would fit but it was tight enough that the threads were catching. I switched to 5/16" bolts that are too loose but still get the job done.

After a good amount of sanding on the edges to get rid of the intense flakes, filing down the holes to be fully cut through, and dropping in all the hardware, everything came together and it was super sweet seeing the full mechanism in action.

Hopefully in the composites week I can play around with some of the more complex iris designs and possibly integrate the whole thing into a tabletop with an integrated trash can.