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Difficulties Connected with Non-Standard Mirror Requests

Requesting non-standard mirrors will result in increased costs. There are several reasons for this. Firstly. non-standard mirrors require unique tooling that has to be created for a single job. This costs money and additional time. Also, I maintain an assortment of blanks up to 10" having pre-generated curves. Having to grind these blanks into different curves (even if just one f number) will take considerable time.

Secondly, the production of a unique item can result in problems when the item comes back from the coater and a surface defect is detected that was unobservable prior to coating. This results in having to re-work the unique item rather than fabricating a new item or using another identical item made at the same time. (A defective standard item can be re-worked and re-sold at a later date, a unique item can not.) This can result in considerable delays. In the case of domestic orders I ship the mirror directly to the purchaser from the coater. With a standard item, if the mirror has a surface defect I ask the purchaser to use the mirror until I can send him a replacement. In the case of a foreign purchaser, where I examine the surface prior to shipping, the mirror must be held, re-made and re-shipped to the coater and then back to me again - very time-consuming and often frustrating to the purchaser unless he understands the difficulties involved.

Please think carefully when considering ordering a non-standard mirror, a standard one will very often do just as well.