Roy Smith wrote:

Yesterday I was holding in my hand a grub screw. A rather ordinary
object, costing no more than a few cents, but I realized I have no
idea how they are made.

The threads are no problem, but how do the get the allen-head
indentation in the end?


I'll make this WAG based on no first hand infrmation whatsoever:

They forge the allen socket first, then place/hold that blank on a hex
spindle matching the socket while they cut or roll the threads onto it.

Then, they harden and oxide finish/plate them.

Jeff
--
Jeffry Wisnia

(W1BSV + Brass Rat '57 EE)

"As long as there are final exams, there will be prayer in public
schools"