The idea for our project began with Alexis thinking about a music box. Typically, a person is spinning around on top while the music plays. From there, we somehow got to having a boat with a giant squid coming out of the water.
With this idea in mind, we began looking through the 507 mechanical movements website to find our desired motions. We selected 39, 68, and 100. Shown below.
Our plan for these movements was as follows: movement 39 would move the boat in a circular motion to give it a bobbing motion. 68 and 100 would be used on the giant squid. Movement 100 would raise and lower the squid, while 68 makes it so that the squid would slowly rise out of the box.
Next, we created the drawings for our project. We used makerbox to quickly make a box. The gear generator was used for 39. For 68, initially, we were going to make it ourselves, but as noted by previous students, image trace does not work well here. Doing a quick Google search, a link was found to a former student’s blog post from 2017. Shout out to Noah Kenner for including the downloadable link to his Adobe file so that we did not have to do it ourselves. For 100, the image was uploaded to Adobe and then traced over. Since this system is a lot simpler than 68, it was not tricky to recreate. Shown below are the image and my drawing made in Illustrator.
With our drawings completed, we worked to create a low-fidelity prototype out of cardboard. Some of the cardboard available was a lot stiffer, which made it much better for creating functional gears. We found the good cardboard after making the gears out of wood, as the first cardboard we used did not work well for our gears.
Our low-fidelity prototype demonstrated our three intended movements. It was at this point that we realized movement 39 was going to be more challenging than expected. It is towards the back of our prototype in the photo above. Getting the small gear to go around the larger one on a vertical axis was certainly not going to be an easy feat. Movement 68 worked well; we just needed to refine the spacing. Movement 100 worked well, although not properly integrated into the design.
Over the midterm recess, no progress was made on our project, leading to a grind on Wednesday and Thursday to get gate 3 completed. Our low-fidelity prototype lacked precise spacing of our components, so the first step was to figure this out. We continued working with cardboard for cutting while we refined the spacing. We cut two more versions in cardboard, but only cut the floor and a wall, as the rest of the box was not needed. After a few iterations, this was our current model.
It was still very much messy, but was more refined. The spacing for 39 and 68 was proving to be challenging. For starters, the center holes for the dowels were not actually centered, despite using the centering features in Illustrator. We believe it had something to do with how the gears were made, since one file came from the gear generator and the other from a previous student. Additionally, it was at this point that we made a pivot to remove movement 39. The gear spacing was challenging, and the movement was very complex to actually get right. Instead, we agreed to place the gears side by side and attach a stick to one gear to hold the boat up. This will give a similar motion as before, but simplified.
After testing in cardboard and making the pivot, we moved to our first wood model.
It was far from perfect, but we scrambled to get it ready for gate 3. The spacing for 68 was still a mess, movement 100 worked well, the dowels were not cut to length, and our new boat movement was still a work in progress. To improve the boat mechanism, we made the gears larger, as other teams did not have the same gear issues as us. They had also used the gear generator, so we assumed the larger gears would work better. For us, this proved to be true. The new gears still did not have a properly centered hole like before, but having larger gears helped mitigate it. For movement 68, Alexis properly centered the holes, and we doubled the gears. After a lot of tinkering, Alexis got movement 68 working smoothly. Our project was coming along nicely. Now, we had to make the boat, the squid, and the rest of the box, then some post-processing.
For the design of our boat, we looked online for free files. The first boat we tried proved to be too complex to be cut at such a small scale, so that was scrapped. Eli then went searching for a simple, easy-to-cut boat. Finally, he found one, but the file was designed for a thinner wood material than we had access to. We had to improvise with the design, which worked out nicely. The giant squid was much easier to make, especially since it was kept to being 2D.
The boat, squid, and crank were all spray-painted. The box was coated with tung oil and some vinyl was put onto the the outside of the box and the box was finished!
Cost Breakdown
- 2x 2’x2’ plywood 3/16 – $12.99
- Spray paint –
- Aluminum sheet 3/16” = $26.28
- Dowels 5/16” – $8.99/20 * 3 = $1.35
- Cardboard – Free from packages
- Hot glue gun with glue sticks – $6.39
- Miniwax Tung Oil – $14.98
Tools
- Epilog Pro 48”x36” – Free at oedk – Very expensive otherwise
- Bandsaw – Free at oedk – Between 180-200+ otherwise
- Makercase – Free
- Adobe Illustrator – Free at OEDK – or around $23 per month otherwise
- Gear generator – Free with EDES 210
- Wood file – $14.99
Labor Costs
- ~20hr/person x $18/hr = $720
- Increase in hourly wage as skills have gone up by now
Total: $811.94 without including full cost of other machines. With would easily be a few thousand.
