Note: If you do not want the plate glass tooling that goes with the achromatic blanks just add the letters 'NT' to the part number, e.g., ACF4.10NT.

The blanks are furnished with the mated surface machined. These surfaces are used to polish each other. The opposite (outside) surfaces of the achromatic blanks are machined also and the matching plate glass grinding/polishing tooling is supplied for these surfaces.

The tolerances you have to finish at are as follows: Radius tolerance is 1/20%; finished thickness tolerance is +/-.010*.

The system design was contributed by Max Bray, Phoenix, Arizona.

Please note that these kits are not recommended for a person who has not polished glass or mirror blanks before. The chances of making a mistake are much greater and costs for replacement materials are much higher. For discussion on fabrication and cementing of the lens blanks, please refer to the following articles:

"How to Make a Lens", Telescope Making 3, p.34.

"Cementing Achromatic Lenses", Telescope Making 28, p.16.

See the appendix or our web site for additional information called Grinding & Polishing a Lens by Max Bray on how to polish lenses used in an Achromat arrangement.