Introduction, Belgian Ulster rep

[Erich]

I'm fairly new to Sevens, so by no means as well experienced as others here. One other thread system to have access to is British Association. Most(if not all) British electrics used BA. The dizzy and dynamo use this. It is based on a Thiry thread which is a metric thread developed for the clock making industry in Switzerland. As adopted in the UK, it was rounded off to the nearest decimal. The largest is 0BA and gets smaller as the numbers go up. I think 6 BA is about smallest you'll encounter. The brilliance(IMO) is that like Whitworth and BSF, the crests and troughs of the threads are radiuses, so there is less chance of stress fractures. Model makers still use BA threads with regularity. A final thread(s) is British Standard Pipe which comes in BSPT(British Standard Pipe Tapered) and BSPP(British Standard Pipe Parallel). Drain plugs and fuel and oil lines come with this size. Sorry for the detail, I'm a bit of nut(;-)) for British threads.

Erich in a rainy Seattle.