Champaign-Urbana Community Fab Lab
Champaign-Urbana Community Fab Lab

Soft Circuit Assignment – Andrew Sun

For this project, I wanted to go with the theme of recycling. I chose to do an Earth design for my patch, and a colorful green fabric for the bag itself. When I started embroidering the patch, the green continents came out quite well. However, once it started doing the oceans, the bobbin thread started to show on the top. At first, I thought it might be an issue with the thread getting stuck, so I stopped the process and rethreaded the machine, but after a few stitches the problem returned. I asked some of the staff, and they said it might have been an issue with the size of my design (it appeared a lot larger in PE design), so I decided to make my design a bit larger and start over. The continents were still fine, but once again I had problems with the ocean thread. Unfortunately at this point I didn’t have enough time to completely redesign my patch, so I just continued with it. Later on when I was almost done with the pouch, I noticed that the     blue thread was slightly thicker than the green thread – this might have been why the machine had problems with it. If I were to redo this project, I would probably try it with a thinner thread (or maybe a different machine) to see if it gave a better result.

My finished patch (the white looks like ice, which is actually pretty cool)

Oops! (Hooray for seam rippers)

One mistake I made for this project was sewing the bag fabric together with the zippers before doing the circuits. I wanted the battery and switch to be accessible from inside the bag, but in hindsight this was not going to be possible, so instead I had it sandwiched between the inside and outside layers. The bag got in the way a lot, and I even accidentally stitched the inside and outside layers together. For future reference, I would strongly recommend putting the entire circuit on the patch before sewing it to the pouch. The circuit was surprisingly difficult – for my first attempt, I think the battery holder was broken; it only worked if I pushed hard on the battery. I had to remove all the thread and try another holder; this time it worked fine. To avoid the problem of the conductive thread overlapping, I arranged the LEDs so that the negatives were on one side, and the positives on the other. I also taped down the thread to prevent it from getting loose.

Patch plus zippers

Sewing the conductive thread

In the end, the design turned out pretty well!