> Don't have U-tube....... do either of these finally show how a
> 2500 year old surface was cleaned to cleanroom level
> cleanliness i.e. all particles greater than or equal to 0.0001"
> and all organic residues completely removed?
> Archae Solenhofen (email@example.com)
You are totally out of your depth.
This method of measurement has been used for well over a century and is still today used in the aerospace industry when a quick and reliable indication is required, not just on metals but transparent plastics and various types of glass.
You now seem to be deflecting by claiming that the modern restoration involved skilled machinists entering the boxes and working down the surfaces to a high planar tolerance.
I'm sorry but you appear to be in your death throes. You don't appear to understand the difference between a flat surface and a polished surface.
Here are the videos again..
Just let people watch them and make their own decisions about whether or not the straight edge method is viable or not .
So therefore readers, just click on the links. Enjoy, and make up your own minds.
Here's another method using "feeler gauges" and a straight edge, instead of the "light leak" method.
This guy is working between 0.004 and 0.007 that's 0.003
That is three one thousandths of an inch, or three "thou" as we say in UK. One and a half times the thickness of a human hair.
Chris Dunn would have had no problem measuring the flatness of the inside of the boxes, using his easily portable straight edge combined with a flash light and/or feeler gauges
Post Edited (07-Apr-15 20:52)