[ATM] 16 1/2" mirror grinding-NEED HELP

[Jim McPherson]

Hi Bob,
         Sounds like your mirror is making good progress. What can we 
help you with?

-Jim
horace r davis wrote:
> appreciate input on type of strokes to get the desired f5 focal length
>     center depth .200
>     Telescope mirror log 16.5 inch mirror
>     Started Jan 2007
>     Tool: 5 inch diameter pipe phalange
>     Beveled edge 1 hr
>     Hogging out mirror
>     2 hr first light center under straight edge
>     4 hr not using enough grit less .05
>     3 hr increased grit center depth .069
>     1 hr center depth .076
>     10 hr
>     1 hr center depth .089
>     1 hr center depth .106
>     1.5 hr center depth .120
>     Center 2/3 of mirror was hogged out buy the other 1/3 not touched
>     Increased length of stroke to reach the edge
>     2 hr center depth .149
>     1 lb * 60 grit used at this time
>     17 Jan 15.5 hr
>  
>     Thank you,
>     Bob Davis
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