Right now I interested in the motions of camshafts, so when we had the opportunity in class to create a mockup that I wanted to make that first! As cute as v1 ended up being, I think I became too ambitious at too small of a scale with this attempt. I wanted to see what it would look like to have different cams shapes for each section but I also made them all eccentric. Problem one: it was difficult to make the shapes of the cams neatly, causing the flat followers that I made to get stuck on the rough edges. Problem two: since they were all eccentric cams of differing shapes meant that the flat followers would move around erratically. As well as I didn't account for the long side of each of the shapes to fit very well in the box that held them. Problem 3: I made the slide holes too wide, which also caused the followers to flop around. I tried to fix this by adding so much hot glue into the cavities to make up for the missing material.
Over the reading week break, I created a larger four-section camshaft as a second prototype. At the larger size, cutting went much more smoothly as well as I learned from some of the mistakes from v1. Firstly even though I am very interested in the different motions that can be created by other shapes of cams I decided it was best to stick with a circular eccentric cam for all four sections just to get the movement and understanding of the build down. The flat followers run much more smoothly across the new cams.
I wanted each of the followers to rise and fall at different times so each cam is rotated about 45 degrees from the one in front of it. In this version of the prototype, I still had only one level of the slide and I found that the followers still would flop around even though the slide holes were only slightly larger than the shafts compared to v1.
So I created a second level slide! This fixed the issue handily. After thinking about it for a few days after this build I most likely didn't have to make the second level slide so tall, I probably could have laid it right on top of the first one.
Well, I will try that in the next prototype!
This working camshaft leads me into what I have been thinking about for the kinetic project.
I would like to create a similar box as my v2 prototype but be able to have fans pushed and pulled by the followers. I want to use the wave-like movement that is already being created by these eccentric cams in sequence and with the fans to bring about an ocean splashing effect.
I have been able to make a somewhat working proof of concept of this:
I was only able to make one of the camshafts into the concept as I realized with a bit of testing that there would need to be a counterweight for the flat follower in order to pull the fan back down the slide and I only had one coin-type piece of metal that was heavy enough to use for this experiment.
I am quite happy to see that it works okay right off the bat! I think that there will need to be some small amount of weight on each end of a fan to help pull it more open. I also think that making a V-shaped slide would help to ease the fans shut as they descended. I am not sure that is something I could do with the laser cutter? Some more experimenting is in order!
PS. I had forgotten that I already had some foam core at home and I picked up an approx 2x2 ft sheet at Dollarama and I think I like this cheaply made type much better for prototyping!
You can see the regular foam core on the top and the paper is much thicker which takes more strokes to cut through. The Dollarama foam core the paper is much thinner so a new blade just cuts through it like butter. The center foam seems just strong enough to build without issue since I made all of v2 using it. And best of all it was $1.25 so I don't feel like I have to be as precious with it as I did with the foam core in class, which makes me feel better about larger-scale prototyping and general mistakes and rebuilding.
THIS IS SO GOOD! Can't wait to see more.
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