Author Topic: Wanted: Buy or borrow Original manual for Edwards McLeod vacuum gauge.  (Read 1338 times)

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Offline TerraHertzTopic starter

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Pic is of an Edwards production of the McLeod gauge for measuring vacuum.
It needs some restoration work, and in preparation for doing that I find that there does not seem to be ANY online scan or text of whatever original manual Edwards sold with these gauges. Not even a single photo of it.

What I want is an original paper copy of that manual, either to buy or borrow. So I can scan it and put it online.
The McLeod gauge is still a very useful thing, for calibrating mechanical vacuum gauges. And the online pages about using it are pretty poor.
« Last Edit: March 21, 2017, 02:37:34 pm by TerraHertz »
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Offline noidea

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Hi Terrahertz
I don't have a manual but remember using these when I first started in my trade 30 years ago as a refrigeration fitter, for measuring what is considered high vacuums in our industry (0.1 mm Hg) as electronic gauges were only just making inroads back then.
It's a long time since then but the basic principle of using it is that you  have the gauge tilted horizontally so that the two narrow measuring tubes are subject to the vacuum of the system. You the slowly rotate it anti clockwise so that the mercury travels back up into the measuring tubes. When it's vertical you zero it by adjusting the scale to zero off the right hand column of mercury and read the vacuum by the depression of the left hand column.
 


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