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This is an easy to make little project that will really come in handy around the shop. The design for this compact compass is simple and uses common parts, but has a wide operating range – approximately 1/2″ to 7″ circles can be drawn using it.
I made a short video of how I made it:

I made a single page PDF that includes the template, and this can be downloaded here:

Compact Compass

Most browsers will open this directly and you can print it from there (set to “actual size” or “no scaling”). You can also right click the link above and select “save link as…” – this will save the PDF to your computer.

UPDATE: I’ve been using this for the past 5 years and it has proven to be a solid performer. And although the wood version is still working just fine, I thought I’d make a new one, but this time using aluminum:

Still soft enough to work with normal woodworking tools, but a lot more durable than solid wood of the same thickness. I laid out the shape of each arm freestyle, using washers for the circles.

Cut out with a hacksaw and fine tuned mostly on my belt / disk sander, which is perfect for this kind of thing:

The bottom arm (the one the pencil fits into) has a counterbore for the head of the #10 bolt to fit into, but the bolt needs to be filed down to fit flush. I drilled a 3/16″ hole in a block of wood and clamped that in my quick release vise:

I could then glue the bolt in with epoxy and let it cure. A change from the original is how I used a push pin for the pivot point on this one:

Simpler and more reliable, the push pin gets epoxied in as well.

When dry, I put it together and tried it out:

Works great!

I made a video on making this new version: