I was so excited about the idea of tidy bobbins I went to Home Depot & picked up a roll of the tubing. I could not cut it with the Exacto knife though. I finally found I could use cheap utility scissors I found at a swap meet to start a cut then I rolled the tubing as I continued to cut which now made a single thickness. Then it was fairly easy to cut the ring. I sometimes had to clean up an edge but it works great. My neighbor's husb. is going to take the rest of the tubing & use his jigsaw to finish cutting up the whole thing. I'll have lots of rings for friends. Thanks so much for sharing this site.
Pat