An acquaintance of mine has this square and is seeking info. I haven't seen it myself, but he says it has no maker's marks. It has holes on the arm that look like they are for a carpenter's pencil. Perhaps for layout, or marking an arc or circle.
Seldom if ever find maker's marks on one of these. Very common carpenter's tool & predecessor to speed squares. The diamond shaped holes are for a carpenter pencil. Never used one for an arc myself, but marked rip or offset lines on boards.
Mortise/tendon layout 4 post/beam construction.
Got a quick answer from Kirk Eppler on Facebook- Seen in a Southington Hardware catalog from 1930. Called a scribing square.
I used to have that same type of square. I know it had numbers stamped on it for the holes I think they were whole numbers with fractions at every hole, so if you put a pencil in the 1"1/8" hole you could scribe a line 1"1/8" from the edge of the board.
Mine did not have a makers mark either but it was very handy to use and surprisingly still square being made out of lightweight steel.
It is hard to tell from your picture but it looks like the end of the rule part of the square has a radius on one side and mine had that as well. I thought some knuckle head had stuck it into a grinder.
This is the picture of the page the square is on. I don't see the radius on one side.
I can see drawing a circle, using any slot, or a spot in the oval on the head as your center point. Place a pencil at the desired radius, whether it be a slot, or the edge of the square. Not the most convenient way to draw a circle, but would work in a pinch. Regards, Lou
Quote from: Papaw on October 15, 2019, 03:25:04 PM
... I don't see the radius on one side.
Is the inside corner of the arm rounded?
Thanks for that Papaw.