Though this topic has been covered several times, here is my take on a low cost but effective hold down clamp system. It uses a Lee Valley router bit that cuts T slots in the spoil board. I think you can find similar bits on Amazon. I used a slot pitch of 96mm as a nod to the metric system but anything will work. The original idea came from CNCNutz but I 3D printed mine to allow a domed washer and knob that provides a good clamping force at a reasonable angle. The T Slot bolt is also available from Lee Valley but you can also use brass toilet bolts. The blocks clamp 1/2" on one end and 1/8" on the other but other sizes will work just as well with a little re-design.
Good idea, and that store looks pretty cool as well!
I’m thinking of trying the T-Slot system myself. I have the threaded 1/4"-20 inserts recessed every 50mm x and y, but the darn mud-dobbers keep trying to pack them full. I made my clamps similar to yours, but with a rounded head allen bolt that is recessed into the clamp itself. Just use my mini drill with a low torque setting. Also, my clamps are made of wood. Can’t tell you how many times I grazed them with no harm done to machine/bit.