Interns Corner: MAKE Robot Project

CNC & Machining
Interns Corner: MAKE Robot Project

By Nick Raymond
Photos by Gunther Kirsch & Nick Raymond

Working at MAKE is anything but boring. On any given day, someone might walk into the MAKE Labs and say, “So I was thinking about building [fill in the blank], can you help me?” The people here are open to the idea of collaboration and trying new ideas, one of the things that makes working here so great.

Recently, I was sitting at my workbench fiddling with some project for the magazine when one our sales folks, Cecily Benzon, walked into the Lab with a special and urgent request. The idea was simple: we needed to WOW a potential advertiser, to inspire them to open a box filled with material about MAKE and Maker Faire. The project had to be interactive, visually appealing, and fit into a standard shipping box. There was also the added challenge of making something that would not get tossed in the garbage or be some impractical desk ornament. After brainstorming for a while, we decided, “Let’s make a custom lid to the box; something that will really spark their curiosity, that can later be hung on a wall as a plaque or picture.”

But we had three questions:

1. What should it look like?
2. What should it do?
3. What materials should we make it out of?

The first question was easy. I immediately thought of our Maker Faire robot mascot. What better image to put on the lid of a box than a popular company icon? Of course, this meant I needed to enlist the help of MAKE designer Michael Silva, to ensure that the project would not drastically alter the appearance of the logo. Michael also helped me design the files used to cut out the robot, and helped me figure out the overall look and style of the project. (Thanks Mike!)

In trying to figure put what it should do, Cecily had proposed that we buy a programmable greeting card with a speaker and amplifier and take it apart for the simple electronic circuit. We would then hack the lid to play a prerecorded message once the recipient opened the box. We liked the idea, but were worried about the reliability of the sound mechanism and how we might attach it to the box lid and ensure that it would survive shipped across the country. I had never taken one of those cards apart, and since this project had to be completed in two days, I really didn’t want to spend all my time tinkering with a cheap electronics circuit. Not to mention, if we were actually able to program a message, what would we say?

After rummaging through a random parts bin in the Lab, I found two large red panel-mounted LEDs. These were a perfect fit for the robot eyes. We decided to go with a simple circuit to light the eyes, including a toggle switch and replaceable battery. This would ensure that we could ship the box with the lights turned off and that the batteries would not be drained once the package arrived.

In addressing materials, we had several options. The Lab is outfitted with 3D printers that extrude plastic, CNC routers that can cut wood, and a laser cutter that can very accurately slice thin sheets of cardboard and acrylic. After weighing our options, everyone unanimously agreed that we should cut the robot out of ⅛”-thick sheets of colored acrylic using the laser cutter. TAP Plastics sells acrylic in various colors and thicknesses and can quickly cut rectangular sheets down to size as needed. Mike took the vector image of the robot and used Adobe Illustrator to generate three separate cutting files.

It was Mike’s idea to add depth and dimension to the robot by using small spacers in-between the white and red layers. We found a handful of ¼”-tall aluminum spacers. These were pre-cut to the exact size needed for our project, but we quickly changed plans once I discovered that each spacer would cost 25 cents. Due to the robot’s layout, we wanted to use at least two machine screws per body panel. If we had used one machine screw to secure each body panel to the white background, we ran the risk of parts twisting and rotate during shipping. Since we needed upwards of 44 machine screws and spacers, the pre-cut aluminum spacers were not within our budget. I knew there had to be a more cost effective alternative.

A little discouraged, I walked around the hardware store for a while, contemplating whether I should just purchase a piece of aluminum tube stock, the stuff sold at hobby stores, and use a pipe cutter to make my own spacers. But I really didn’t want to cut and sand 44 spacers down to size, and I knew that inevitably, some of my DIY spacers would be longer or shorter than the others and it would not look right. I was about to give up and drive back to the office empty-handed when I decided to walk through the hardware aisle one last time. It was then that I noticed a box of ¼-20 nuts sitting out on the counter. EUREKA! These nuts were about the thickness that I needed, and not only were they uniform and shiny, they were CHEAP! I grabbed a box of them and a box of 6-32 machine screws for mounting the body panels to the background and rushed back to the Lab.

It was time to cut out the robot parts using the files that Mike had designed. Before cutting out the final acrylic parts, I used scrap pieces of cardboard to cut out a full prototype of each layer. It’s a good thing we did, as I forgot to tell Mike to add a few extra holes for the eyes. Cardboard is a great prototyping material, especially with the laser cutter, and it is easily found in our recycling bin at work. Once Mike fixed the files and we  verified that everything lined up, it was finally time to cut out the acrylic pieces.

We used three different colors of opaque acrylic for the robot, all ⅛” thick. The sheets were cut at Tap Plastics to 12”x24”, which cost about $45 for all three sheets. With this much material, it is possible to cut out two entire robots. The blue acrylic was used as a background, with the white acrylic serving as the second “outline” layer, and the red as the body panels. The red and white layers were separated using the ¼-20 nuts as spacers, and everything was secured together using the 6-32 machine screws with nuts and washers mounted on the backside of the blue background. It was a bit tedious to assemble all of the screws, but the laser cutter is very accurate, so everything fit together nicely and the holes lined up just right. (I LOVE laser cutters!)

After a quick bit of soldering to hook up the LED eyes to a toggle switch and battery pack, the project was complete. Mike and I looked over the final product, beaming with pride, and handed it off to Cecily and the marketing team to pack it up and ship it off. What started out as an idea quickly developed into a collaborative design, and finally a finished project with glowing eyes and stylish good looks. Just another day at MAKE Labs…

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