The importance of calibration

Fast Eddie

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Not just calibration, but absolute measures, datum points, and ultimately, not trusting anything from China (according to the original post on Linked In the middle tape measure is Chinese):

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robs ss

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Scary - unless that's fake news. Then that's scary too!

(BTW - your phone's down to 35%)
 
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It's just an Alternative Measure, that's all.
Move on folks, nothing to see here.... :cool:

Must be very useful to the vertically challenged amongst us - I wonder if there's another version to make one slimmer as well?
 

Saber

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Are we assuming the tape measures have the same starting point? It's covered up in the photos.
 
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Many engineers do not know what the maximum allowable error should be in their measurements. On all engineering drawings there are tolerances specified. Your measuring equipment should be able to measure one third of the drawing tolerances. I.e you should be able to measure one third of the tolerance on the measurand. Also many engineerrs do not know how to calculate safety factors for materials. For steel, thinkung of a number and doubling it gives the right answer, if you are constructing a building. Aircraft materials are often stressed to 95% of their limit of elesticity.
 
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In AUS we call that downsizing, instead of putting the price up they put less weight or size, the food industry has been doing it for years and of course they say they are looking after the comsumers health by eating less or drinking less, but of course the prices do end up going up.

Ashley
 
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Q, where these tape measures manufactured in Wuhan, as I believe they have sent out a bad batch while the balance of their mind was disturbed . . . . .
 

Fast Eddie

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Q, where these tape measures manufactured in Wuhan, as I believe they have sent out a bad batch while the balance of their mind was disturbed . . . . .

I thought your Wuhan reference was gonna be about them under measuring / under counting things...!
 
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My first tertiary qualification is in Applied Science. Science is about measuring things. Engineering is based on science. If you don't calibrate your measuring equipment, science becomes irrelevant. Dynos , in particular are often good at measuring improvement, if their repeatability is good. But for comparison of the power of bikes present and past, they are probably not very good. I think that Heenan and Froude test brake that Bob McIntyre used, would have been properly calibrated with a dead-weight tester. However history is probably irrelevant when you are developing a race bike.

 
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Joe Craig claimed his Manx Nortons were developing 50 BHP. I have ridden Triumph 650s which were claimed to produce 46 BHP as well as a 500 cc Manx. Both were quick enough, but a Manx is better. I wonder what a good Commando 750 would show if run on a properly calibrated Heenan and Froude brake ?
 
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In Australia, engineering companies which have ISO9000 quality management system certification, usually have their measuring equipment calibration traceable to the standards in the National Measurement Laboratory in Sydney.
 
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