Sewing Needle Holder
I made two needle holders. Not sure which one will be best. I'll edit this when I print both and figure it out.
This thing was made with Tinkercad. Edit it online https://www.tinkercad.com/things/cC4rLtwKely
Edit 9/7/2018: I printed the needle holder with square holes and it worked great, albeit a bit thin on the cap. It's robust enough to hold a few needles. To clarify, this holds needles used for cross stitching and sewing, not for injecting medicine.
Edit 9/24/2018: I split the two holders into two separate files.
Edit 9/26/2018: I added a new, bigger, threaded holder. Haven't tried printing it yet, I'll change the file if it doesn't work.