Adjustable Prismatic Square

This small square was my first ever toolmaking project. I wanted a small square to use when squaring blocks in the mill. There wasn't material available to make a one piece square, and I'm still unsure about how silver soldered machinists squares are ground on all sides after assembly. So, the base and blade would have to be two pieces, and why not make them adjustable. I didn't go for a traditional rectangular blade like often seen in combination squares because grinding such a thin part would be very challenging, and grinding the mating slot nearly impossible.

Instead I used a square profile blade clamped at 45 degrees. This allows for easy clamping with the clamp remaining withing the edges of the base. The clamp is spring loaded so it loosens easily. The blade is made from a M2 HSS tool bit and the base is 1095. Its a fun little quirky square. I didn't do any formal design for this; no sketches even. As a result the proportions are a little clumsy but that doesn't effect its use.   

Close up of clamp with blade in a middle position

Small relief for checking an outside corner