22" f/3 Mirror Project by Jerry Wright |
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Play Video Clip: | Rough grinding the 22" mirror on the John Wikswo machine. The focal length of the finished mirror will be 66" (f/3). | |
Play Video Clip: | Rough grinding continues but the desired curve depth (sagitta) is getting closer. | |
Play Video Clip: | Desired curve depth reached, now the curve needs to be spread out to the mirror's edge. | |
Play Video Clip: | 120 grit fine grinding. Goal is to remove the coarse pits from rough grinding, and to achieve and maintain a spherical curve. | |
Play Video Clip: | 220 grit fine grinding. | |
Play Video Clip: | Fine
grinding the 22" mirror with 5µ grit. Next step will be polishing. |
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Play Video Clip: | Polishing
begins. Stroke arm problem is noticed. |
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Play Video Clip: | Polishing
resumes. Improvements made to stroke arm. |
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Play Video Clip: | The
Singing Lap. |
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Play Video Clip: | Figuring
begins. |
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Play Video Clip: | Lap
facet overhang (viewed from below). |
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View Photos: | Rough
grinding the 22" mirror, working towards the desired sagitta (depth of
curve). |
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View Photos: | Oven photographs. Details of the
"Jerry-Rigged" oven used for drying the plaster tools. |
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View Photos: | Fine grinding the 22" mirror. |