76.5mm CNC PCB holder

Inspired by another model like this, except their's was too small. Designed for a 76.5mm x 103mm board (what I get from Amazon, 3"x4" I think) is what I started with, but ended up with the smaller clamp fitting inside the main, so you can pretty much clamp any size board as long as the length or width is the 76.5mm. I created this guy to mill and drill with out changing everything out. The main clamp is about 85mm long (76.5 wide) with the smaller clamping to the top where ever you can fit it, the edges are 1mm in width. The M4 t-nuts use a M4x12 screw, washer and M4 nut, just use a pair of pliers to fit the nut into the hex hole - tight fit.