If I wanted to buy a bunch of 4.5" long shafts, 3/16 or 1/4 inch
diameter, mill finish, with one end turned down to 4mm with a 1mm flat
(to make a "D" 4mm diameter and 3mm from flat to round), about 5mm or so
long, with the shoulder profile being quite unimportant.

Prototype runs of 10 or so, production orders of one or two hundred.

My understanding is that this is a job for an NC lathe, and that most if
not all of them would have an attachment for milling the flat, so the
operation would be feed, turn down, cut the flat, cut off, repeat.

What I'm not so sure of is where to find someone interested in those
sorts of volumes, and if I can get this below the $13 that the one
online machine shop I tried wants. I'm also not sure of where I can
compromise on specs to get the price down (the "D" probably has to be +0
- 0.005", the shaft can probably vary +/- 0.005", since it'll be running
in plastic bearings).

Any guidance appreciated.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

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