Two weeks ago, a few of us ladies here at OMC, along with some of our friends over at Otherlab, participated in the Expanding Your Horizons conference hosted at UC Berkeley to help educate young girls about STEM careers. The conference gathered about 500 girls between the ages of 11 and 14 to learn about STEM fields from female students and professionals in various tech industries.
When our team sat down to plan our workshop for the conference, we were overflowing with ideas. We eventually decided that we wanted our girls to walk away with a basic understanding of electronics and something physical to help remind them of the principles they learned. We wanted the activity to be hands-on and most importantly fun!
Daunting though it seemed, we decided to mill out 60 double-sided circuit boards on the Othermill before the event and have each girl learn to solder one into a necklace on-site. The circuit was simple: one LED, one resistor, one battery, two wires, and a metal clasp to act as the switch. Our colleague Leanne Luce designed a beautiful board in the shape of a firefly.
Once the design was done, it was time to prepare our Othermill factory. I set up one file to cut the circuit side of two fireflies, with an L-shaped box around each of them to help with alignment on the second side. Then I set up another file to mill out the design side of the firefly, using the alignment jig to help with top-to-bottom registration.
Unsurprisingly, milling 60 of the same thing is not the simplest of tasks. Even though we got our cut time down to 10 minutes/side, it took around 40 hours to make all the boards we needed.
One of the things we had an especially hard time with was getting the design side of the boards to come out right. At first, we planned to cut all the way through the copper (the same way we did on the circuit side). However, with this strategy, we were having a very high scrap rate. We were using a rather large tool for the job (1/32") to save time and were having a lot of trouble with the leftover copper curling up off the board. We thought this might have been a depth issue, and in adjusting that, we ended up accidentally discovering a quite beautiful effect by etching the copper only a few thousandths of an inch deep.
We loved the look of these boards and decided that this effect was our new goal. But this came with its own set of challenges. Unfortunately, objects in reality, unlike our virtual designs, are not perfect. We only had a range of a few thousandths in the z-axis to work with and our boards were a) not all exactly the same thickness to the thousandth and b) held down by double-stick tape and therefore not perfectly flat. We eventually figured out a good strategy and flow to crank out perfect boards most of the time, and after a week of on and off focus, we met our goal of 60 boards.
The experience at the workshop itself was fantastic! The girls were very engaged, asked intelligent questions, and had a blast. One highlight for me was having a 12-year-old tell me that she wanted to have my job when she grew up.
Expanding Your Horizons is a nonprofit entirely focused on inspiring young women towards careers in STEM. They host over 35 conferences here in the States and a total of more than 100 conferences worldwide. If you’re interested in getting involved, either as a volunteer or a participant, check out their website for information about when the next conference is happening in your area! For more information about the workshop we put on, visit Light Up Lab.