What better way to celebrate Pi day than to eat it? But what if you love cookies? Last Thursday we tried something new and fabricated a Pi shaped cookie cutter out of sheet metal.
The first step was converting the drawing to a file to be cut on the water jet, and making a metal version of the cookie, just because…
Next, we used the water jet to cut out a rectangle the right length, complete with rivet holes. We contemplated which order to make the bends so that the bends wouldn’t collide with the un-bent material, and we decided to start at the inside of the legs, and work our way around so the rivets would be along the top. After careful measuring on the model, we made the first few bends using a hand held sheet metal bender, and the larger vice mounted bender.
We made the last few bends, and after a bit of final adjustment the result was beautiful!
A few days ago we had some scrap 2.5mm 1/8″ titanium end up in the workshop, left over from a previous job. I had never handled the raw material before. I could tell it was strong and resistant to flex like steel, but it feel light like aluminum. I knew this metal would be great for an aerospace project, so I designed some hub mounted arms and cut a prototype out of slightly thicker aluminum. This has some of the smallest holes and details that can be cut on this machine. The triangle fillet radii were cut slightly larger than my model specified.
Here they are all together. I think it looks quite nice, though It’s a bit on the heavy side and I think the aluminum could be thinner. Not as thin as we could go with the titanium. There are certain features that can definitely be thinned a bit more to shave off some weight. It’s so much fun to see an idea transform from a drawing to a tangible object!
I love modeling in Solidworks. Here’s how it can fold.
When I realized I would have access to an industrial waterjet what’s the first thing that came to mind? “What fun stuff can I cut up?” of course. Starting off the list is a regular slab of rock. It’s abundant and we hadn’t tried it yet. I scrounged a local dried up creek bed for a few prime candidates and it cuts like butter, especially considering the thickness. Check out this geology!
We wanted to get interlocking spinning gears, but need to play with the teeth pitch a bit more and cut at a slower speed. The gear on the left (below) was cut significantly slower than the two on the right, but all show a bit of ghosting (for lack of better term) at the base.