Wednesday, September 23, 2009

Cross-Hatch

We cross-hatched our mirror to see where we had contact between our mirror and the tool. The tool is convex and the mirror needs to be concave, so that it will reflect the light from the stars better.
This is the line test. The mirror has lines on it, so that what when grinding it you can see where you have contact and where you don't. The lines came off after the second charge of 60 grit. We now have good contact!!



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Naming a Blog

Choosing a name for a blog is very difficult and fraught with dangers, but in consulting with Mary Kathryn, my dear bride, we decided on "Kenning through Astronomy Divine."

The name comes from Meditation 6 by Edward Taylor, a New England Puritan, pastor, and physician. Every week he walked hunderds of miles to tend to his flock and care for the sick, and he still had time to be a prolific writer.

About Our Project

In 1978, when I was 12, I bought a book on telescope making at Davis Planetarium in Jackson, MS. It started me on a quest to grind my own telescope mirror. Two years later I order a 6 inch mirror blank and abrasives from Edmund's Scientific only to be crushed when the blank arrived without the abrasives. Edmund's had stopped carrying them. Over the next 30 years, I had thought about grinding that mirror that I had been carrying around for so long. Now as part of a homeschool Astronomy class with my children, we will complete a project 32 years in the making. I hope you all enjoy following our progress in this. We hope that it culminates in February or March with a West Virginia Star Party that will include some of my nieces and nephews.

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