CNC hold down blocks

First order of business, prior to even calibrating the machine is to create some hold down blocks to clamp the work.  My friend had used these pretty cool ones called pinchblox, but their website seems to be out of commission, so I decided to make my own.  Basically they have a notch on each end, one for 1/2 inch material, and the othe for 3/4 inch.  They go in the t-slots milled in the cnc table and then clamp down with a nylon wing nut.  I could have made them out of wood, but wanted to try some plastic as I have never really worked with that material before.  I looked up a local plastic supplier (Lion Engineering) and went and visited them.  They were very accomodating and gave me a 30 minute tour of their facility.  I had no idea there were so many types of plastic.  I had planned on UHMW, as I had at least heard of that, but they talked me into some high density which was about 1/2 the price, running around $20/sq ft.

It machined very nice, and I created a little video documenting the process.  Hopefully future posts will be a little more exciting than clamps..

Machining the plastic hold downs