STI thread gauges for BSW, Whitworth thread

Whitworth is the oldest standardised thread of all and still turns up on British machines, classic vehicles and older installations. The flank angle is 55° instead of the 60° of the metric thread, and the crests are rounded. STI gauges check the oversized thread that later receives a thread insert. It is a series of its own, because the receiving thread is larger than the working thread that follows.

VÖLKEL offers 12 versions, from BSW 1/8 x 40 to BSW 1" x 8.