2020-03-27 (F) Weekly Summary

When I was still picking out handle material, I bought a foot (300mm) of polycarbonate, aka Lexan, pipe. One reason I picked it was that the online measurements were precise, and I knew it would be durable. In the end, I built a single handle with this material because I didn't want to burden everyone else with the cost if I could find a cheaper alternative.
Clear handled prototype

I haven't done a lot with improving the blade design since my other teammates were eager to tackle that issue. I suspect they wanted to jump on the part that tossed sparks, and I don't blame them. In the meantime, my solution was aluminum tape over the rubber blade, and the more I used it, the more I liked the idea. Since it might not last a long time in a knife fight, I figured the best course would be to have spare strips of aluminum on hand, so I drafted a CAD file with templates for the two types of rubber knives I had on hand.
Screenshot of blade shape templates

I had enough experience and usable parts, so I started building a final run. I planned to construct three identical knives to make sure all my pieces fit together. If that worked out, I would buy the fourth set of components, and go through a final build with pictures so I could make concise instructions. I was waiting for parts, so I detoured for a few days.
Semi-flexible water pipe with a blade shoved into the end

Even though the aluminum tape was working out, I still wanted to experiment with different materials, like "conductive rubber" and Velostat. The rubber was actually a silicone sheet with embedded carbon fibers, and it was expensive. I already had some Velostat on hand, and more places online sold it. I tested rubber cement and E6000 on both materials, but only E6000 and Velostat stuck.
Adhesive test

By this point, I had a knife blade with an old hole pattern, so I tried a full-scale piece of Velostat even though I knew it might destroy it. When I applied E600 to the plastic, it curled up. While the glue cured, I kept it pressed, but the wrinkles persisted. Even though the plastic and rubber stuck together, it was ugly.
Wrinkled Velostat on a knife blade

One night, I was feeling squirrely, so I wrote a silly article based on the exhibition fight rules the team agreed upon. Here is a link to the PDF with the script.

The rest of the summary posts have been arranged by date.

First time here?

Completed projects from year 1
Completed projects from year 2
Completed projects from year 3
Completed projects from year 4
Completed projects from year 5
Completed projects from year 6

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