A list of stuff you will need for making a mirror.
| 1) | Telescope mirror kits are available from Willmann-Bell, ASM , United Lens or Newport Glass for a short list of sources that isn't necessarily complete. You can also build up what you need from these sources and a piece of glass from almost anywhere. If you do get your own glass, make very sure that the glass is well annealed or you will have problems with astigmatism as the glass relieves itself over time. |
| 2) | A bucket to wash your mirror and other parts out with. Mirrors up to 10" can use the 5 gal. or so white plastic buckets that are seen everywhere, especially along the roadway and in trashcans. Larger mirrors will quickly get to the point where you will need to use sponges or rags (use one per grit size or you'll transfer grit and get scratches!) and the bucket for a water source for washing the mirror, tool and other things. |
| 3) | Containers for each of the grits and the Cerium Oxide. Baby jars are often easy to find and do a good job of holding the material. Also get a small container or dropper bottle of glass or plastic for the Cerium Oxide so you can make a thin paste or thick wash with the stuff. You may also want a watertight container to hold the mirror and tool (good ol' burpware is very good) so that you can keep them in contact between polishing and figuring sessions without them drying out. I use the water bottles like from Evian, etc. with the pop sealing tops for holding grits ready to use in grinding as the water and grit mix makes for a quick and clean application of the grit to the tool. |
| 4) | Base to hold the tool steady. This can be a piece of 1/2" or thicker plywood that you can clamp down to a tabletop is fine. My solution was to get a 60lb. piece of steel from the scrapyard and put it on a lazy susan bearing. It doesn't move at all when pushing on an 8" piece of glass. You will also need 3 pieces of wood to hold the tool in place and 3 screws to hold them in place. You should be able to push fairly hard against the base and it won't move. Make sure that anything sticking up from the base is well away from where the tool is so that you don't hit the obstruction with the mirror. 1.5 times the diameter of the mirror from the edge of the tool is about enough space for a start. |
| 5) | A quiet place to do the mirror that's pretty dust free. A shed or the basement is fine although I do my work in the bathroom. There's nothing like getting the mirror almost polished out and then finding a new scratch because you are working in a dirty environment. |
| 6*) | An end cap for iron pipe if you are going to do the tile tool method. Either Galvanized or black pipe is fine. If you have a piece of steel or iron floating around the house that's pretty round, with a flat (or a bit convex if a small radius is desired) surface for a bottom and about 1/4 or less of the diameter of the mirror to be ground then that's good enough. A bronze gear have been successfully used by at least one person that I know of. |
| 7*) | Ceramic floor tiles for the tile tool. The kind that are hard all the way through, not the glazed ones of plaster. The size of the good ones are about 1" and have a square or hexagonal shape. Either variety is just fine. You may also want a cutter for them if you want to fill out the size of the tool to the edge. |
| 8*) | Dental Plaster or other plaster of similar strength for the tool and a bowl to mix the plaster in. |
| 9*) | Duct tape or a piece of flexible plastic (a vertical blind is one source) to be used as a dam for the plaster you pour onto the mirror. |
| 10) | A pan to warm the pitch with so you can pour it. Be careful with the pitch as a very small piece of it will make a very strong laxative and you will be very miserable until it gets out of your system! |
| 11) | A eyeloupe of about 10X or a 1"FL lens for inspection of the mirror for pits. A 25mm or so eyepiece can be used if you desire and you can get the focal plane of the eyepiece outside of any obstruction so you can put it near a flat surface and focus the image. |
| 12) | Foucault Tester and mirror holder. This is something that you can build or buy. Building one can be done with the information at these various pages. I note to you that there are several different types shown. All of them do the same basic job and the basic idea was invented in the 1850s by Mr. Foucault who did the classic stationary pinhole and moving knife edge. The latest versions have a moving light source (typically a LED now) and the knife edge is also used to partially block that source in the slitless version (which, I might add, is very easy to build). |
| 13) | A black marker so you can mark the big pits on the backside of the mirror and other jobs of marking that may be needed to be done. |
| 14) | A medium grit sharpening stone to make and keep bevels on the mirror and tool edges. Any cheap knife sharpening stone (the red and black stones are pretty cheap) will work nicely here. |
| 15) | A spray bottle for spraying water on the mirror surfaces as needed. When filling the bottle, use about 3-5 drops of detergent per 8oz. of water to allow for the better wetting of surfaces. |
| 16) | A (preferred painted) stick or rectangular metal rod or long ruler to make the facets in your lap or a facet mold to do the same. |
| 17) | Last, but not the least, a plentiful supply of water for washing and cleaning. Don't use your sink unless you like to run a lot of water at high rates for a while to wash the grit down the sink. It is better to throw the water out on the ground. You will also want a place where you can throw the water full of glass and other stuff that won't look bad. Often a corner of the grass is a nice place just before you water the grass. The water with the stuff in it is pretty environmentally safe except for the dust which can cause silicosis in if inhaled in large quantities in the lungs. |