- 1). Purchase a mirror kit which will include a pyrex mirror disc and a ceramic tool disc. These discs will be flat and evenly thick. They will become your mirrors for the telescope and the pyrex mirror will be placed above the tool mirror. This helps coordinate the distance along with the grinding (to make its curvature).
- 2). Determine the radius and focus length you want. For instance, using a 6-inch diameter mirror you can make the radius curvature 72-inches by making the focal length 36-inches.
- 3). Rough grind the discs. You will use fine sanding or a sharpening tool. Grind the edges of the disc to produce a concave curve. Use a stroke in the shape of a "W" when near finished grinding.
- 4). Smooth the mirrors. Use a finer grade of grit when sanding to smooth out the edges.
- 5). Clean work area. Once the grinding and smoothing is done you will need to remove everything related to the grit so that there is nothing left behind. You do not want to get fibers onto your mirrors. Spray laquer on your sharpening tool if you used it for the previous steps. Lay down newspaper where you will begin polishing.
- 6). Prepare to polish the mirrors. This can take at least 10 hours to finalize. Buy the polish that is made up of cerium oxide and water. Then develop what is called a pitch lap. The pitch will be included when buying a mirror kit. Wrap masking tape around the sharpening tool. Pour pitch into a pan you will not use again. Heat at a low temperature and stir until there are no more lumps.
- 7). Pour pitch onto tool. Pour slowly and carefully until there is 1/2-inch thick of pitch on the tool. The tape used on the tool will keep the pitch on the tool. Once the pitch hardens then cover the mirrors with a thick layer of cerium oxide. Place the mirror down onto the tool that has the hardened pitch. Circle the mirror around and do the same on the other side. Let it dry. Then place the mirrors on the telescope.
- 8). Put the pyrex mirror disc above the tool disc in the telescope. There should be two plac
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