Homemade insert tool holder with homemade inserts

.A multi radius corner rounding insert holder. The inserts are made from hardened gauge plate. Out of interest the radii were machined after hardening using a tapered solid carbide end mill.
This tool is a "working" tool and therefore not MTES (Made To Exhibition Standards) it was conceived during a small production run of prewar(WW2) spark plug caps, where there were several corners that needed consistency to look "professional", and is another example of 'if you want, make it' which is the philosophy behind all invention.
Any questions please feel free to ask