Nut sizes imperial measurements, disorientation!

I've heard of those, but never encountered them.

There are indeed some oddball metric threads about, but the thread I have in mind is way more common. Most adults & a lot of children would have actually screwed or unscrewed the item that has this thread.

Cheers.

Stewart.

Hot water bottle?

Way more common than that.

Bottle and Jar threads are listed in an old book I have , it simply lists about every thread you could think of!

Andrew.

Drain Rod threads appear to be Whit form, 7/8 or 3/4" ( From poor memory A While since i made an "unstopper" using broom handle and the rubber disc, for our daughter )

Howard

Yes: Drain Rod Threads are 7tpi BSW form! I can't recall the diameter without going and dragging them out to measure, but I don't think it's as large as 7/8" .

How do I know?

I made parts for a pump for a caving application, with a drain-rod section as its piston-rod / handle. It starts a siphon to drain a short "sump", a pool totally filling the passage with water, like a sink-trap.

I turned a brash bush with male thread, to fit the plastic piston that works in a short length of 150mm PVC drain-pipe. Calculating the wheels for an EW lathe with 20-65 X 5T change-wheels, two-stage only and 1/8" lead screw, was interesting.

'

I used that lathe too as a 2-axis dividing-head for drilling about 130 holes in a plastic tube for the pump's inlet strainer: using a hole through a brass block in the tool-post, to guide the bit in a small battery-drill. Workpiece between centres.

Fibre-tip pen marks on the 60T change-wheel on the spindle as angle indicator sighted against a headstock feature on the headstock as their "pointer"; similar but separately on the lead-screw for lengths. Guide-block against the work as angular brake, normal saddle lock for lengths.

Drinks bottle threads?

Good evening all.

The thread I had in mind is the Schrader valve thread. Invented by a German in the USA.....Says it all really!

Cheers.

Stewart.

Is it Unique though as there are several different sizes of the Vg thread form and the common tyre size Vg8 is just a 60deg 32tpi thread

I would have said threads like Edison, plastic bottle and glass bottle forms are fare more unique in shape though again have several size options

Edited By JasonB on 27/02/2023 19:26:28

Good evening all.

As far as I know there's nothing else that uses it. Bloody Yanks!

Indeed bottle threads are very unique in form, and there are considerable variations. Think how many times a day bottles get unscrewed vs how many tyres are pumped up. I wouldn't like to be the chap who had to count them!

Cheers.

Stewart.

My candidate thread in all our homes and probably operated by more people than is the tyre-valve thread, is that used on glass jam-jars:

A rounded-top, flat-bottom profile, multiple-start breech-thread; i.e.perhaps 4-start but cut through to give a quarter-turn action for a female thread that is no more than tabs!