. 418 moleswortii’s pocket-book
Screws. j
Angle of thread = 55°. I
Depth of thread = pitch of screw.
a of depth is rounded off at top and bottom.
Nlimber of threads to the inch in square threads = 4 number
of those in angular threads. -
Depth of threads i= -64 pitch for angular, = -475 pitch for
square threads.
Whitworth’s Standard Nuts and Bolt-heads.
1 Diam. of Bolt, inches. Width across flats. I Thickness of I Nuts. Thickness of Bolirlieads. Diam..ofBolt 1 at Bottom of Thread. Di am. of Bolt, inches. Width across Plats. Thickness qf 1 Kuta. Thickness of Bolt-heads. Diam^of Bolt at Bottom of Thread.
1 •338 i ’1093 •0929 - 1* 1-8605 It •9843 ■-’942
•44g To •1640 • 13+1 H 2-0483 11 1-0937 1-067
i •525 i •2187 •1S59 if 2-2146 14 1-2031 1-1615
• 6014 Æ •2734 •2413, H 2-4134 if 1*3-125 1'2865
4 7-1 •7094 .» •3281 •2949, if 2-5763 I« 1-4218 1'3688
• 8201 1% ’3828 •346 1 2’7578 If 1-5312 1-4938
•9191 i •4375 • 3932 U 3-0183 If 1-6406 1'5904
Io 1-011 Æ •4921 •4557' 2 3*1491 2 1'75 1'1154
3 1-101 i •6468 ■5085 2> 3-337 24 1•8593 1-8404
1-201 fa •6015 •571 । 21 3-546 21 1-9687 1’9298
4 1*3012 *6562 •6219 23 3'75 21 2-0781 2■0548
To £•39 •7109 *6844! 24 3-894 24 2-1875 2-1798
i 1’4788 •7656 •732? 21 4-049 2i 2’2968 2-3048
15. lö J. *5745 ■if •8203, • 7952j 2J 4-181 24 2*4062 2-384
1 1’8701 1 •875 | •8399 3 4-531 3 2’625 2-634
Whitworth’s Standard Gauges, deposited at the
Standards Department, Board of Trade.
Range from, 7 inches .. 5 liate of iu- ) crease per > gauge .. } No.of gauges i per set .. 5 Decimal. Fractional.
•01 to •! •001 in. 81 •1 to 1 •05 19 1*1 to 44’2 to 6 .. f 1 30 J 10 i to 1 TS 15 ' U to 4 4 J 21 to 6 i 8