English or metric. How to tell?

[Patrick Chadwick]

"I have also accumulated a large stock of BA, UNF, metric, Whit, BSF and cycle fasteners over the years."

With 400 sq ft available! Try harder.

"I don't say the above to brag..." Neither do I

But to the above list I can add such quaint items as Panzergewinde (German conduit thread), British conduit, BSP, NPT, ACME, ME, UNC, UNEF, metric series 1mm, 0.75mm, 0,5mm and some oddballs (like multi-start taps) that really puzzle me.

I learnt a long time ago to keep all machined thread items (nuts, bolts, spindles...) from every piece of dismantled equipment that I could get my hands on.

Motto: it might come in handy one day. 99% will probably never be used, but the usable 1% is priceless.

- Of course, the trick is to find it when you need it!

But if you want to refurbish old rifles (back to 1670 to date) then you need to be a bit flexible about things like thread forms.

Today's useless information: did you know that the barrel thread for a Luger pistol is 18mm diameter x 20 tpi? Eat that, standards fanatics!