Huh. The holes looked bigger. Maybe it was a close-up photo. 200 mesh means 200 holes per inch, so it must have been the same.
Mesh is graded by the size of the items that pass through it, not by the number of wires per inch.
Market grade mesh of 180 has holes to pass items 0,0033" and
Market grade mesh of 200 has holes to pass items 0.0029"
There are different scales, but Market Grade is what we have been dealing with here.
Check the rightmost columns at https://en.wikipedia.org/wiki/Mesh_(scale)
I received mesh of both grades and the 180 has about 78.4 wires per inch and the grade 200 has about 80 wires per inch.
The size of the wires were slightly different. The 180 uses 55 micron wire and the 200 uses 50 micron wire.
I doubt that those meshes differ much unless it would be in the quality of the nickel used. Both sources claimed high grade mesh.
Burnishing them with Palladium was much easier after they were roughened up with sandpaper.
Deneum's use of Nitrogen to purge their system was impressive and very professional.
Most people probably shouldn't try this experiment without a mass spectrometer or Residual Gas Analyzer so that they can "see" what is happening.
Our team's plan is to purge using D2 and repeating the purges until the Residual Gas Analyze says that the system is clean.
We will report how many repetitions it takes so that others can gauge how long it takes if they choose to not use the mass spec. or RGA.
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