Tripod/Camera Screw Thread

[Dave Osborne]

Hello Folks,

There was a discussion on here maybe earlier this year, maybe last year about whether the thread on a tripod/camera was 1/4-20 Whitworth or UNC. ISTR we got into discussions about thread angles and somebody pointed out that Wikipedia was (allegedly) wrong.

Thing is, I can't remember who had the last word, and I can't find the discussion on Google Groups.

Without wishing to open the debate again, did anyone find the definitive answer, cos my colleagues and I were having fun recently with a load of (supposed) Whitworth bolts/nuts and studding, some of which was compatible and some of which wasn't!

1. Stud would screw into camera
2. Bolt would *not* screw into camera
3. Nut would screw onto *both* stud and bolt

Cheers,

Rumble

[John]

As I recall, it is Whitworth - the camera standard was set before UNC was introduced in 1948.

UNC is a 60 degree form and Whitworth is 55 degree. Pitch is the same - 20 threads per inch. Obviously there are manufacturing tolerances which may explain your experience.

[Mike Clarke]

It's Whitworth. I've just fished out one of my ancient cameras that dates back to the early '50s when the standard was Whitworth. It's held in it's ever-ready case with a screw which goes into the tripod bush and has a female thread on the bottom for mounting on a tripod while in the case. The screw fits my current digital camera and also mates with the screw on my fairly recent tripod. So I'd say that the current standard is still Whitworth, or is given a generous clearance so that both Whitworth and UNC will fit.

[RW]

Running fit thread.

Normal

Nuts are usually always slack (Fnarrrrrr !)

[Dave Plowman (News)]

It may have been in the UK - but the UK was never a major camera maker?

The other one that hasn't been mentioned is American Coarse.

[Steve Firth]

No such thing as American Coors. It's all brewed at the old Bass factory in Alton.

[Andy Champ]

AFAIK the thread is the same everywhere. Certainly my tripod has fitted fine on a German, a Japanese, and an American camera.

So I googled...

"I think you will find that 1/4" BSW (British Standard Whitworth) is close enough to 1/4-20 UNC (Unified National Coarse) to be considered interchangeable for non-critical applications such as this (if this were an airplane, I'd think differently). The differences are out in the third decimal place, being on the order of 0.005" or less.

This interchangeability is fortunate, since BSW is considered obsolete and is approaching extinction (Britain having gone metric), while the UNC should be around for a good while longer. Certainly tooling in UNC is a lot cheaper than BSW." (this was in a discussion about Rollei, so not toy cameras)

"The de facto standard threading for the screw that attaches the camera to the tripod is Whitworth 1/4"-20 for small cameras or Whitworth

3/8"-16 for larger cameras. (This otherwise obsolete thread system is similar to the Unified Thread Standard still used in the USA, but with a different thread angle.)

Most cameras and tripods?even those manufactured and used in countries which use the metric system exclusively?are built with Whitworth tripod threading."

HTH

Andy

[Dave Plowman (News)]

Sounds like you should lay off it for a while.

[Steve Firth]

The probability of me drinking Coors is about the same as the probability of you sitting down for a nice pint of petrol with a paraffin chaser.

[Dave Plowman (News)]

How do you know I'm not a fire eater?

[Steve Firth]

I haven't seen you in the Cathedral close.

[Grimly Curmudgeon]

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember Andy Champ saying something like:

So, in the world of photography, there will be a small corner that is, forever, Britain.

[Bruce]

More of a small helix, really. ;-)

[nightjar]

That was rather the point of the Unified thread - to provide something that would work with both British and US standard threads, to improve interchangability between allies during the war. They were, incidentally, used in some aircraft equipment although, according to my late father who was an aircraft instrument fitter, where the British aircraft were designed so that you could dismantle anything with a standard toolkit, the Americans would design the aircraft first, then a set of specialised tools you needed to get to the fixings they had put behind things.

Colin Bignell

[Grimly Curmudgeon]

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember "nightjar" saying something like:

Reminds me of an old RAF airframe guy who told me the Spitfire was an utter bastard to repair battle damage on, as everything was crammed in and needed lots of time to take panels off and rivet back on, whereas the Hurricane was repairable with a pot of glue and a bedsheet.

[tony sayer]

In article , Grimly Curmudgeon scribeth thus

Yep thats what my dad and uncle told me too, and they used to do those very jobs;!...

[1501]

Yet the tooling remains readily available and, according to the supplier, will continue to be available for the foreseeable future.

[dennis]

The Hurricane won the battle of Britain as the spitfire didn't have the fire power to bring down the bombers and there were ten times as many Hurricanes. Somehow they couldn't pin a medal on a piece of furniture.

[Andy Champ]

The Spitfire won the Battle of Britain, because the Hurri didn't have the speed to keep the 109s off. Or it was the Defiant. Or the barrage balloons. Or the Home Guard.

Or perhaps they all played a part?

Andy

[dennis]

Probably the people really. It wasn't the spitfire as is frequently told.