Moonrise Over A Mountain – My Midterm Project

If anyone has been binge reading this blog, you may notice an absence of posts since about a month of this post’s publication. This is because the first Big Project of the semester came around: the dreaded midterm. Designing, drawing, cutting and assembling your own unique project takes a toll on everyone. WEll, the month-long development period has finally finished, and I’m proud to present my project titled “Twilight over a Mountain.”

Kind of corny title, but at least it has one

The back mechanism. Simple, but effective

As always, there are a few distinct steps I took when developing this device. This time there were 5 main steps: Planning, Designing, Cutting, Refining, and Assembling. They each took around a week, with Assembly being the exception. In the first step, Planning, I had to decide what my project was going to be and draw rudimentary sketches that I could later transfer to the cutting board. I went through several possibilities, including a cuckoo clock and a jack-in-the-box mechanism using springs, before settling in the moonrise design. I choose it because it did not require ordering materials, effectively showcased the Geneva Stop mechanism without adding unnecessary complexity, and looked pretty.

With the planning done, now came the (first) hard part: Designing. THose paper sketches are useless to the laser and plasma cutters, so I had to redraw my design into Illustrator. The problem? Illustrator is bad at accurately drawing gears. The solution I came up with is complex, but functional. Bear with me:

  1. Go to http://hessmer.org/gears/InvoluteSpurGearBuilder.html and design the gears to your liking. There are other gear generators online, but this was the most effective for drawing rack and pinion gears. If you need more than 2 gears like I did, draw the first pair then change only one gear and download both files.
  2. Download the .dxf files from the gear generator nd open them in SolidWorks. Mess with the settings a bit (import them as sketches), make them 3D, then save as .stl.
  3. Import the .stl files to TinkerCad, rescale them if necessary, then export them as .svg.
  4. Open the .svg files in Illustrator.

And voila! Accurate gears in Illustrator. There are probably better ways to do this, but this is the one that works for me. Just make sure that your gears are correct at step 1 or you have to start all over again.

With the gears done, I moved on to Cutting. Pro tip: you’re going to use more wood than you expect. Test cuts and prototype cuts and recuts and recuts and… By the end of this step, you’ll know the perfect way to cut any piece of wood. Hopefully. I was lucky and only had to cut most things twice. All of my project is laser cut wood except for the Geneva Stop, which is made of plasma cut aluminum. The mountain stand I cut twice, one without holes and one with holes. The one without holes had them drill pressed so that I knew how the gears would best mesh, then I laser cut it again with holes. I also drill pressed the center hole into my aluminum piece using a laser cut piece as a guide.

First laser cut pieces

Second batch, now full size

Moving on, I entered the 4th step, Refining. The base wood I dyed black and the back gears walnut to give them a distinctive look. The aluminum gear I angle grinded, then sandblasted, and finally etched with the fiber laser. All of my wooden gears were treated with tallow and sanded at the edges to make them fit better.

Dyed base, newly-cut moon rack and upside down mountain

Etched aluminum gear

Finally, I Assembled my project. The base and stand were cut to fit perfectly, but the bottom edge of the stand was somehow too long and the base curved. A lot of sanding fixed that issue. Then, I secured my gears to the stand using small wooden cylinders (which took ages to sand so they spun nicely) and blocked off the edges by super gluing laser cut wooden stoppers on them. I added a small knob on the central metal gear. Finally, I finished the device off with a plaque at the front.

Cutting the axles

Honestly, this was an amazing project. Could it be better? Sure. I wanted to test how different dyes looked on the mountain stand, and the base could be better adhered to it. But overall, I’m proud of my device, and all my classmates who gave their best. Shoutout to my teammate Scout, whose planetary gear mechanism leaves me speechless. Go check it out. And now, I’ll go take my well-earned spring break. Sayonara!

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