lou
Aluminum
- Joined
- Feb 20, 2005
- Location
- Redding, CA
For some reason I feel that I need an Optical Flat, and like everyone else I'm trying to get the most bang for a buck. Ox Tool did testing on a surplus Russian optical flat Russian Optical Flat Testing - YouTube
From the results of his Youtube test, it looks like the Russian flat are very attractive in quality and price. This is a typical eBay flat Optical Flat Parallel Top 6 mm (Flatness . 7mm - . 28”) | eBay
If you look at the title of the listing "Optical Flat Parallel Top 60mm" and other listings will be "Optical Flat Parallel bottom 60mm". The difference between the 2 descriptions is wording "top and bottom". I'm going to make an wild assumption that wording of "parallel top" means that 2 surfaces, top and bottom, are parallel within a given measurement. The wording "parallel bottom" the top is not considered any measurable function of the optical flat.
An example "parallel top" would mean that it could be used to check the flatness and parallel of a micrometer spindle faces. The "parallel bottom" would not accurately function for this type of test.
From the results of his Youtube test, it looks like the Russian flat are very attractive in quality and price. This is a typical eBay flat Optical Flat Parallel Top 6 mm (Flatness . 7mm - . 28”) | eBay
If you look at the title of the listing "Optical Flat Parallel Top 60mm" and other listings will be "Optical Flat Parallel bottom 60mm". The difference between the 2 descriptions is wording "top and bottom". I'm going to make an wild assumption that wording of "parallel top" means that 2 surfaces, top and bottom, are parallel within a given measurement. The wording "parallel bottom" the top is not considered any measurable function of the optical flat.
An example "parallel top" would mean that it could be used to check the flatness and parallel of a micrometer spindle faces. The "parallel bottom" would not accurately function for this type of test.