British Association Screw Threads : BA Thread Chart

[Richard Gawler]

Richard Gawler submitted a new resource:

British Association Screw Threads : BA Thread Chart - The history and salient dimensions of BA threads including tapping drill sizes

BA screws and nuts are useful for model making because the sizes progress in a geometric sequence.

Read more about this resource...

 

[Andrew Taylor]

As BA is a Metric standard, it may be more useful to have the metric sizes instead ( which are here)

British Association screw threads - Wikipedia

en.wikipedia.org

 

[Richard Gawler]

I have my doubts. This particular Wikipedia article omits tapping hole dimensions (which are surely the one thing the modelmaker can reasonably want to look up); it omits data for sizes 12, 14 and 16 BA (which we want to use); and it implies that threads continue down to an absurdly small 25 BA.

 

[JimG]

Russ Elliot's chart on the CLAG website gives all BA sizes up to 16BA with tapping and clearance drill sizes in millimetre sizes. Imperial sizes would be from the old number drill series which are getting fairly rare these days.

BA screw sizes

BA screw sizes

www.clag.org.uk

Jim.