It is not always convenient to uses a vice to hold an object or piece of material when milling. It is often better to use clamps and spacers to hold down the item. These small step clamps give you 2 mm steps from 4 to 24 mm and can be used with a separate bar or on there own via the bolt slot. I have used 25 mm square aluminum bar which is a common stock size. The cutter used is a 5 mm slot drill as it entails a lot of pocketing operations

Note: The Code has only been tested on my own converted milling machine using Mach 3 software. You may need to edit the code to suit the feed speeds and parameters of your own machine. The start reference point is the top left hand corner and a tool clearance of 2.5 mm. The G-Code consists of plunge rough routing and horizontal finishing routines.