I am currently working on a project that will require me to swing an arc with an 18 in. radius. I have trammel points with a scribe on either end but won't hold a pencil or marker and I also have a couple of smaller compasses. So this is what I was able to come up with. Everything was made from scraps and or recycled stuff. I can now swing an arc with a 24 in radius. I love making tools! made with oak dowels, and oak scraps from an old dresser.