CNC Hold Down Clamps with changeable contact heads

There are many different hold down solutions on Maker World but all of the ones I'd seen and used had the same issue.  You needed to print a lot of different parts and if you managed to break or nick one while the CNC was working you needed to reprint the whole clamp. 

To address this I made a clamping system with a replaceable head to allow you to swap on different heads based on the thickness of the material and should one get damaged, you can just replace it and not the rest of the clamp.  Each head provides a full ½ inch or 12.7mm of clearance from the front face of the head to the clamp.  I made the heads in sizes from ¼ inch to 1-½ inches and can add additional sizes if needed.  Note, each clamping head is designed with a 1/8" “tooth” that comes down to allow for you to apply some downward pressure to the piece being held and account for minor variations in thickness.