BA threads are used for sizes under 1/8 inch the older British fastener system.

You'll find lots of BA threads on any British car, but only for fasteners smaller than 1/4". BA fasteners have their own set of spanner sizes. Typically, a set of "Whitworth" sockets will include a OBA (and maybe a 2BA--bigger number = smaller size) socket.

BA size chart, for BA nuts and bolts. Skip to primary navigation; Skip to main content; Skip to footer; Macc Models ... Over Thread: Threads per inch: Pitch: Diameter at Thread Bottom: Tapping Drill Size: BUY Taps and Dies: 16 BA: 0.0310 inch: 133.3 tpi: 0.0075 inch : 0.0220 inch: Number drill 73 0.6 mm

2013年2月12日 · British Association Standard Screw Threads are used mainly for instruments and clocks. The BA-series screw threads should not be used for new designs. Instead use the M-series screw threads.

2016年7月23日 · BA sizes are specified by the following British Standards: The angle of the thread is 47.5° [4]: 2 and the depth of thread is 0.6 times the pitch with rounded tops and bottoms.

British Association Screw Threads or BA Screws Threads, BA threads: tapping and clearance drills table

BA sizes range from 16BA (smallest) and 0BA the largest. Look below for a full chart of dimensions and measurements. If you are still unsure either email details or send in a sample for checking. Hex Set Screws Nuts - Chamfered on one side only

2012年3月13日 · Sizes of screw threads in the BA series, major diameter and pitch for each gage from 25 to zero

For most threads there is a choice of drill sizes. Smaller size drills will produce threads closer to the full thread form, larger drills will produce threads with less than the full thread form. The percentage of full thread form is indicated for each drill size (see below).

Home » Technical Pages » Thread Identification Chart » Thread Identification Chart (British) Thread Identification Chart (British) Basic Major Diameter. Nominal Diameter (mm) Threads Per Inch; Inch mm BA BSW BSF BSP BSPT.0118: 0.30 ... BA-British Association BSW-British Standard Whitworth BSF-British Standard Fine BSP-British Standard Pipe ...