Misc: Speedometers Smiths Chronometric Speedometer

bmetcalf

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I always assumed that Chronometric was from Greek for time and measure. Shakespeare used iambic pentameter in his plays and sonnets, per Wikipedia and I hope he wouldn't have anything to do with that meter and gram rubbish!:)

No Greek expert here, I am most familiar with ouzo and retsina.
 

derek

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speedo springs

interesting chat on the 3" speedo. I have just overhauled one for my Comet, but I am missing a small spring that holds the milage recorder paul in contact. Does anyone know of a source, I have tried all of the repair people but they say that they are unobtainable. I can get them from a spring maker b ut minimum order £15. Cheers Derek
 

Vic Youel

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I always assumed that Chronometric was from Greek for time and measure. Shakespeare used iambic pentameter in his plays and sonnets, per Wikipedia and I hope he wouldn't have anything to do with that meter and gram rubbish!:)

No Greek expert here, I am most familiar with ouzo and retsina.

I prefer the rythm of elegiac couplets myself.:):):):

Vic
 

Tom Gaynor

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Chronometrics - and the dashing of Imperial hopes

Chronometrics are based on French Jaeger (therefore pronounced "jejere", not "jager" as I pronounced it for years) speedometers, using French Jaeger patents. Smith took Jaeger over / bought a controlling interest, whatever, and retained the tradename for a while. Upmarket cars had Jaeger speedos, the hoi polloi, us, or at least me, had Smiths. They were in fact the same. However, many of the threads on Smith Chronometrics are from a now obselete French metric thread system, with no modern equivalent.
I'm reluctant to explode the amazement this effortless display of arcane knowledge may (bloody well ought to...) generate. But any VMCC member who read the same six articles on Smith's chronometrics that I read (and scanned, and re-read) could tell you the same.
Where credit IS due, is that several months on I REMEMBERED.
Got to go. Lost the car keys again...

Tom
 
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tractorman414

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methamon

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Burman boxes

QUOTE=clevtrev;13429]
Perhaps I should also mention the Burman box, and the long studs, that go through the two outer covers. They are not 5/16 studs with a Whit thead ate one end and a BSF thread at the other, the body of the stud is 21/64"dia and it`s actually a dowel.
QUOTE]

Trev, please would you elaborate? Is this restricted to CP boxes or does it apply to BAPs and exactly what do you mean?:confused:
 

fgth130

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Strange, I thought we'd put these thread questions to bed in MPH some years ago.
The drawings in the Smith's catalogue's of the era shows the large thread on the body to be 0.718" dia (23/32") x 26 tpi Cycle Thread, and the speedo drive cable nut thread to be 0.5" dia x 26 tpi.
These were measured and confirmed by an Inspection Dept. - hardly a casual guess.
You pays yer money and you takes yer pick.
 

clevtrev

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Strange, I thought we'd put these thread questions to bed in MPH some years ago.
The drawings in the Smith's catalogue's of the era shows the large thread on the body to be 0.718" dia (23/32") x 26 tpi Cycle Thread, and the speedo drive cable nut thread to be 0.5" dia x 26 tpi.
These were measured and confirmed by an Inspection Dept. - hardly a casual guess.
You pays yer money and you takes yer pick.
Quite right they are. But the one I referred to is the input at the back of the speedometer case.
 

clevtrev

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QUOTE=clevtrev;13429]
Perhaps I should also mention the Burman box, and the long studs, that go through the two outer covers. They are not 5/16 studs with a Whit thead ate one end and a BSF thread at the other, the body of the stud is 21/64"dia and it`s actually a dowel.
QUOTE]

Trev, please would you elaborate? Is this restricted to CP boxes or does it apply to BAPs and exactly what do you mean?:confused:

The stud referred to is marked, A , long studs common to both covers.
I wrote stud with a plural, when it`s just a singular one. It works as a dowel in conjunction with the mainshaft.
 

Vic Youel

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Burman gearbox studs

The discussion and diagram in KTB (1989 edition) on the studs is wrong in this respect and does not mention the larger diameter dowel. Note that originally the securing nuts were BSW threads but are best changed to BSF.

Vic
 
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