For our metric members working on old Brit bikes. I just ordered one of these digital verniers with a display in mm. imperial and fractions. It's probably not for a professional engineer. But just over £17 with free delivery in the UK.
http://www.rdgtools.co.uk/acatalog/Vernier_Calipers.html
I can't believe you haven't already got a set of these Ron, you're not still trying to read one by eye..?
They are good value and available at all the shows. You can get better quality ones but they're all useless when the battery goes flat
Then it's back to the original set and reading it by eye
I bought one of these with fractions at Beaulieu last year. It rounds to the nearest 1/64" which can be a bit misleading. Handy for checking screw sizes (and control lever clamp diameters if you don't have a British Standard thumb).
Mine is not as accurate and consistent as it should be when working in thou. I have the impression that it rounds up or down there as well.
Well there's the problem Ian. It's gone and broke itself whilst laying in a draw. I've tried new batteries but it seems to have developed a mind of it's own. I saw these with the fraction readings and bought one. Ron
Hi Matt..Absolutely right...If you need to measure anything accurately and be sure of the dimension use the appropriate micrometer...Verniers are particularly poor on internal diameters.
They are OK if you are machining (measuring) to 'fractional' tolerances..ie + or -.015" (.381mm)... ....or if you quickly want to convert a dimension from Imperial to metric or vice versa..Ian
G'day Ian.
As an apprentice fitter and turner it was drummed into us that a measuring device was only good to 1/10th of the devices scale. ie. A tapemeasure measuring in mm was only accurate to 1 cm, a vernier measuring 1/10th of a mm, to 1mm, a micrometre measuring 1/100th of a mm, to 1/10th of a mm and so on.
Here in Australia we converted to metric in '68 but there are still old lathes and milling machines in use with the imperial scale, so you learn very quickly to become conversant with both systems.
Hi Matty..We have both systems, as we only ever achieved a partial change to the metric system..even today stock material is available in Imperial and metric sizes..pipes come in both formats etc. etc...and as in Oz there is a vast amount of old equipment still around that is all Imperial...
At the time of Metrification the Railways refused from the outset to convert the millions of bolts holding the tracks down from Whitworth to metric..and the Government themselves quickly rejected the idea of changing every road sign in the UK to kilometers!
Whilst the idea of 'standardisation' on the metric system was laudible I don't believe the full implications of costs, the lifespan of existing equipment or the time it might take were fully appreciated. When you think about it every building in the UK was constructed using Imperial measurements and materials...a bit problematical when you come to replacing anything if you have done away with all of the old system...so they didn't.
Now we have an even more non standardised system...
The problem there is that beyond a certain date no one was taught the Imperial system in schools...so people younger than a given age have no idea about the 'Imperial' things that are all around them...Conversely, as I 'pre date' metrification I was never taught 'metric' and just had to pick it up....
However, I did, and still do 'think' in Imperial..when I got Engineering drawings the first thing I did was to convert them back to Imperial before starting the job!..It was just easier for me to work that way and I was less likely to make a mistake...and I can still only visualize weights and dimensions in the Imperial measurements.... .For a period of time machine tools had 'dual gauges' to work in both systems..My own Harrison 300 lathe is all metric..but I soon got the hang of using the metric scales to produce Imperial parts.. ..Ian
Yep, couldn't agree more Ian. I also convert everything back to imperial. But not as important for me as I leave the machining to the experts.
The 58 kg that just appeared on the bathroom scales means nothing to me.....I'm used to seeing my normal 9 stones Ron