[Geof]

Material is 6061 T6.

Picture below shows the tool; diamond with 30 degree tip and .008 nose radius or something like that.

Both parts were finished inside and threaded and roughed on the outside then screwed onto mandrels for the full outside finish. As far as I can remember the final cut was 1800 rpm, around .01" DOC (diameter measure and a feed of .003" per rev., I would need to look at the program to confirm these.

The side hole for the mounting boss was done on a mill.

I should defy you to figure out what it is but I will relent. The mouthpiece on the left gives a little hint but possibly a misleading one. In the jargon of today it is a Human Interface Device aka Mouth Operated Joystick Mouse. It is for people with high level spinal cord injuries who do not have much muscle control below the neck to control a cursor on the PC. Moving the mouthpiece up/down/sideways give full cursor control; puffing into the mouthpiece gives left click, sucking gives right click. All the electronic stuff inside was developed locally by a society for people with disabilities; I am doing the mechanical design and prototyping and financing a start-up company that will manufacture and market it along with some other products for people with a disability.

I am quite proud of it, totally hand coded.