Another "What is it?????"

[abunaitoo]

This one is kind of easy.
But you don't see them much anymore.
263096

[Scrounge]

Trammel points.

[JimB..]

Agree with @scrounge

Do love the old tools.

[Wayne Smith]

Yup, you can still find them in woodworking catalogs.

[bedbugbilly]

Trammel Points - fit on a "wood beam" that is easily shop made in long enough lengths to be able to stick arcs of desired radius. I used these often when I had my custom woodwork/millwork shop. Came in very handy for laying out arched head casings for arched windows. Also used them in laying out large wheels and stole locations for wheels I made for large "walking wheel" spinning wheels that I made a few of. The rims were made of white ash that I steam bent and spliced on a special drying jig I made for the purpose - spokes were turned and a wood split hub that was also turned and the spoke holes indexed and drilled on another jib I made. With these two pieces as you show, you can easily create a "compass" to be able to do layout work - still have my set and they hold a prized place in my tool chest.

[abunaitoo]

Well that was to easy.
I'll look for harder one's.

[Winger Ed.]

Well that was to easy.I'll look for harder one's.

Where do you find all this weird, odd ball stuff?

[abunaitoo]

Most of them I have picked up over the years.
I like old odd tools.
Some from friends.