I've worked on a wooden CNC machine before and it used a basic screw-down system, but I found so many times that I spent as much time hunting down screws and washers and clamping down my work as I did milling simple parts. I also found screw-down systems caused me to use larger material than needed to accommodate the fasteners and to get clearance for the router. I needed something different.
I started by making two sets of plywood braces that would hold the bar
clamps as close to the outside edges of the bed as possible. The
rectangular holes in each must provide for a snug hold but still allow
for easy movement. The braces are held to the Fireball's frame with
three bolt-and-washer connections.
The vise-action side of the clamp would protrude in the front of the
machine attached to the wooden brace in front by two small bolts run
through two small holes easily drilled in the aluminum bar clamp base.
To gain a small bit of clearance I ground off the lip on the moveable
boot for the clamp. About twenty seconds on the grinder and this step