I'm doing the fiddly bits of the Cassegrain subreflector support for the 122 GHz mmWave ham radio project. The wavelength at these frequencies is 2.44 mm and I need to be accurate to about 1/20th of a wavelength on an 18 inch/450 mm aluminium parabolic dish. Positioning of the feed axially and radially, plus ensuring the reflector and main dish axes are coaxial, is quite an engineering challenge. I'm using my Colchester 1800 lathe and Bridgeport mill to make some tiny but precise parts in Brass, Carbon Fibre, Aluminium, Delrin and Stainless Steel
