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Hand ground mirror? Answered

Any one hand ground a telescope mirror, how long did it take approx cost, UK suppliers of necessary parts, is it worth the effort?

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steveastroukBest Answer (author)2011-02-05

I've made a couple. A six inch scope would take about a week of evenings to do. I'll PM you a number to contact

Steve

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Re-design (author)2011-02-05

I don't think it's worth the time/effort/expense unless you just want to be able to say I dim.

This company supplies mirrors to the Museum of Science and History's telescope club in Fort Worth for a very reasonable price.

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steveastrouk (author)Re-design2011-02-06

SurplusShed are absolutely fantastic folks to deal with. Fred, the owner, can never do enough to help you find a weird lens or mirror from the comprehensive collection of stock.

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Re-design (author)steveastrouk2011-02-06

That's right, I forgot that you've actually been there.

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rickharris (author)Dr. Pepper2011-02-05

Not sure, Around 6 to 8 inch I guess - I have been asked by a local youth group if I can help them make a reflector telescope

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steveastrouk (author)rickharris2011-02-05

Hardest bit is the final figuring. Most amateurs have moved to reasonably fast optics, whereas the traditional amateur scope was like F8+ and didn't need parabolising, modern scopes are F3 and lower, and need considerable parabolising.

That said, an unskilled observer might struggle to spot the deficiencies, unless you get to high mags - a really good mirror, on a really good night can stand 50 X per inch of aperture.

Use a Ronchi screen to do the testing and you should be OK, for a small mirror. A big one needs a full Foucaultgram.

Steve

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