French Boat - Imperial Sizes

Sailfree

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I appreciate that with convention and the size of UK & USA markets French boats often incorporate the length in feet in the boat marketed name but really surprised this weekend when replacing cutless bearing to find the P bracket internal diameter really was 1 & 7/8" on a 2004 boat! Shaft was 35mm.

Now we went metric some 30yrs ago but can understand some UK things still being an imperial equivalent - but the P bracket on a French boat.

Is this common on many European boats?

Can anyone advise a reason for this imperial dimension to be used when 50mm would appear to be "more metric!"
 
a pednat writes:

1 & 7/8 inches is 47.625 mm.

so a 50mm shaft would not fit by 2.375 mm, which is 0.093503937008 inches - roughly.

Which is the difference between precision and accuracy.
 
The Frogs are much more pragmatic about these things and use what is appropriate, for example you can get BSP fittings quite easily in France, you just ask for gaz. Perhaps in this case they bought a job lot from China where they had been selling to the US.
 
You should try the Irish Republic .. Copper pipe in 1/2 inch sold in Meter Lenghts .. All fittings still in Imperial .. So the French are no different to anyone else .. You can buy 1/4 of sweets in the Uk or 100 grams .. All our measuring is done in metric / Imperial .. We drive on the wrong side of the road and travel in MPH instead of KPH .. We buy cans of beer in 500ml cans and go out for a drink and buy a pint .. So why should the French not use Imperial ..

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The pednat misses my point entirely!!

I would expect the P bracket to be in metric and 35 shaft cutless bearing is standard with a 50 o/d for the P bracket why does Jeanneau fit a 35mm shaft with a 1 &7/8 o/d P bracket??
 
It could be so that the owners of boats sold into the US market don't have difficulty buying shaft bearings. A 1 7/8" OD, 35mm ID shaft bearing is standard and readily available in Europe as is a 1 7/8" OD, 1 3/8" ID shaft bearing in USA. So US boats could have 1 3/8" shafts but the same size P bracket could be used on all boats.
 
Yes, it is a market thing, the Yanks just can not cope with metric and insist that everything is imperial which of course they invented for their own use, you won't find any of that metric nonsense with its complicated maths. over there, it is also that way in American run plants such as Du Pont no matter where they are located. We 'Europeans' on the other hand, can tackle all types of measurements and calibrations, as we have for centuries.
 
[ QUOTE ]
The Frogs are much more pragmatic about these things and use what is appropriate, for example you can get BSP fittings quite easily in France, you just ask for gaz. Perhaps in this case they bought a job lot from China where they had been selling to the US.

[/ QUOTE ]
BSP is European standard although it isn't called British Standard Pipe. About the only British thread that survived metrication. It is now desribed as Rp, G or Rc.
 
A few years ago I was in Shanghai with a colleague. He went into a shop to get measured for a suit. Waist measurement 36 inches - that's not right he says, I'm at least 2 or 3 inches bigger than that. We later asked some Chinese colleagues about this and the answer was simple - metric inches, 36 to the metre!
 
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