More 122GHz Chaparral® Style feedhorns

I made up another batch of my variant of the VK3CV model choked Chaparral®-style feedhorns. Chokes are 7mm diameter, bore is 2mm, Body is 30.75 x 15mm, with an adjustable 4mm diameter coupling cavity. These are made from brass.

Grooves are 0.5mm wide by 0.75mm deep, made with a toolpost spindle at 14,000 rpm using a two-flute carbide end mill in the lathe at 8rpm

First of the batch fresh from machining.
Batch of 122GHz Chaparral-style horns ready to ship
Microscope view of the 0.5mm grooves
Part-machined battels and coupler bodies
M8 x 0.5mm mandrel to machine locknuts to thickness
Spacer and part-machined locknut on the mandrel ready to machine to thickness
Toolpost spindle drive made to fit my Aloris-style toolpost. 600W, 48V variable speed motor