Search results
Results from the WOW.Com Content Network
Confusion can arise because each Whitworth hexagon was originally one size larger than that of the corresponding BSF fastener. This leads to instances where for example, a spanner marked 7 ⁄ 16 BSF is the same size as one marked 3 ⁄ 8 W. In both cases the spanner jaw width of 0.710 in, the width across the hexagon flat, is the same.
The size is imprinted on the spanners in millimeter values or inch sizes with intermediate sizes in fractions (older British and current US spanners). The two systems are in general not compatible, which can result in rounding of nuts and bolts (i.e. using a 13 mm (0.51 in) spanner in place of a 1 ⁄ 2 inch (12.70 mm)).
Spanner Jaw Sizes Archived 11 January 2010 at the Wayback Machine Additional background information and spanner jaw size table. Conversion chart Whitworth/BSF/AF and metric spanner and thread sizes; ER Type Hook Wrenches
Unified Coarse/Fine diameters and tap drill sizes (U.S. units) Unified Coarse/Fine tap drill sizes (U.S. units) Imperial Metric fastening size conversion charts; International Thread Standards; Conversion chart Whitworth/BSF/AF and metric Archived 2 May 2010 at the Wayback Machine; Spanner Jaw Sizes Additional information and spanner jaw size ...
] BSF threads use the 55 degree Whitworth thread form. It was introduced by the British Engineering Standards Association in 1908. [2] The table provides BSF sizes, the threads per inch and spanner jaw sizes. The BSC column indicates where BSF and BSC threads match. The table shows suitable tapping drill sizes. Uncommon sizes are shown in italics.
Spanners for Whitworth bolts are marked with the size of the bolt, not the distance across the flats of the screw head. The most common use of a Whitworth pitch nowadays is in all UK scaffolding . Additionally, the standard photographic tripod thread, which for small cameras is 1/4" Whitworth (20 tpi) and for medium/large format cameras is 3/8 ...
Tables of BS Whitworth, BS Fine and BS Pipe Threads: V Thread Form (55°) 1 ⁄ 4 ″-20 BSW ISO 68-1:1998: ISO general purpose screw threads—Basic profile—Part 1: Metric screw threads: V Thread Form ISO 68-2:1998: ISO general-purpose screw threads—Basic profile—Part 2: Inch screw threads: V Thread Form ISO 261:1998
Below are some common spanner sizes for metric screw threads. Hexagonal (generally abbreviated to "hex") head widths (width across flats, spanner size) are for DIN 934 hex nuts and hex head bolts. Other (usually smaller) sizes may occur to reduce weight or cost, including the small series flange bolts defined in ISO 4162 which typically have ...