I needed a break. I’ve been working hard on the osPID for several months, and I just needed to not look at code or control algorithms for a little bit. Nothing says “break” like an out-of-left-field project.
I only started knitting recently. Something that’s been bothering me about it is the length of the needles. They’re 14″ long, and I’ve been worried they’ll be bent while riding in my backpack.
It occurred to me that some sort of collapsible needle might be useful in this situation. Taking my inspiration from elastic tent poles, I got to work on my “not PID” project.
construction
The first thing to do was cut the needles in half. I used a pipe cutter for a nice clean cut, then cleaned up the seam with a drill.
With the needles prepped, I then used a lathe to make the supporting inserts.
I didn’t quite get the diameter of the inserts right, so I touched things up at the sanding station.
To get some decent springiness, I looped 3 rubber bands together, then doubled that over. This was pulled through the insert and locked in place with a piece of paperclip. I then super-glued the insert into the pointed half of the needle.
The last thing to do was anchor the other end of the rubber bands in a hole drilled in the cap.
Results
I’m really happy with how these turned out. The weight increase was negligible, and the seam is almost invisible. It puts a slight drag on the yarn, but nothing major, and I haven’t had any hangs yet. Also, because the halves are connected, you can fold the needle with your knitting on it, without worrying that things are going to fall off.
