Machine Screws--Machine screws come with four head styles: round, oval, flat and fillister
Pads are normally attached with Phillips screws but some are attached with the square, slotted type, either fillister
or round head.
Miniature precision fillister
head screws, with modified cone point ends for ready positioning during assembly, are 1-72 UNF parts manufactured to meet the high tolerance requirements of ANSI B18.
There are machine screws, metric screws, wood screws, countersunk screws; with square-drive heads and slotted heads, torx, Phillips, pan head, button head, round head, fillister
head, with high-low, self tapping, wood, metal threads and many more I can't think of right now, but you get the point.
the parts help prevent automatic insertion equipment from jamming and can incorporate flat, fillister
, pan, hex, and other head styles.
This includes an 8-40 taper and bottoming tap, numbers 28 and 19 wire gauge drills, an 8-40 Fillister
counterbore and a dozen each of 1/4-inch and 3/8-inch socket head screws.
Those most commonly used include the slotted Fillister head, Allen or socket head and the more recent addition of the Torx head.
My original set consisted of quarter-inch hex driven shafts with a good selection of bits for Fillister and American Phillips type of screws.
Let's say it is a fillister
head, head thickness unknown, with a length overall of 3/4 inch and with 1/8 inch cut to 5/40.
A hundred years ago a carpenter's tool chest typically would have contained dozens of varieties of planes, and a typical hardware catalogue would list hundreds of varieties (astragals, fillisters
, snipe bills, ogees, Grecian ovolos), each one adapted to a highly specialized purpose.