ATM SUPPLIES NEEDED

LIST OF MATERIALS

MAKE A PLASTER DISK:

Plaster of Paris
Clean Water
Mixing Container*
Mixing Stick*
Measuring Cup
Mirror Blank (as a form)
Plastic Food Wrap (to cover mirror surface)
Cereal Box Cardboard (as a dam)
Alternative: Aluminum Roof Flashing
Masking Tape (to secure cardboard form)
Alternatives: Big Rubber Bands or Big Hose Clamp
Sandpaper or File (for cleaning up the disk and beveling the edges)
Waterproofing (Polyurethane Finish or Epoxy Adhesive)
Paintbrush* (to apply waterproofing)

MAKE A GRINDING TOOL:

Plaster Disk (see Make a Plaster Disk)
Alternative: 1-1/2" waterproofed plywood disk (two 3/4" disks laminated together).
Epoxy Glue (No Alternatives - you need epoxy's strength for this job)
1" Bathroom Tiles, Solid Porcelain or Industrial Grade - Hex or Square
Alternative: Glazed tiles, but many have soft centers and wear through too quickly. If it's shiny on the scuff surface but not on the bottom it's usually an indication that the center is soft. You can tell real fast by scraping the bottom with you finger nail and if it scratches, it's not the best for this purpose.
You should be able to find appropriate tiles locally at your home center or tile store. One-inch unglazed hex tiles can be mail ordered from Willmann-Bell, P.O. Box 35025, Richmond, VA 23235 in one square foot lots. (Catalog item only, not on their web site).
Cardboard* (to mix epoxy on)
Mixing Stick*
1" Disposable Brush* (to apply epoxy)

POURING A PITCH LAP:

Plaster Disk: Alternative: Tile or Glass Tool you used for grinding this mirror.
Pitch: You need about 0.5 kg or 16 oz for a 6" or 8" lap. Use Gugolz 64 or Tempered Burgundy for working at room temperature. See our Grit, Polish & Pitch page for more information.
Pitch Pot*: Something to melt the pitch in and pour it from. Many people use coffee cans, or buy a very inexpensive pot at a yard sale or dollar store. A double boiler arrangement works well, and prevents overheating the pitch; you can stand a coffee can on a metal ring made from a cat food can in a pot of water.
Hot Plate or Electric Stove: To melt the pitch. (Fire hazard - do not use an open flame burner)
Mixing Spoon or Stick*: To stir the pitch, smooth it when poured and pop any bubbles.
Liquid Cerium Oxide: Used as a release agent, so the mirror will not stick to the pitch when pressing.
2" Wide Masking Tape: Used to make a dam around the plaster disk.
Razor Blade or Utility Knife: Used to trim the lap, and clean up the channels.
Channeling Tool: Used to press channels into the soft pitch. 3/8" Wood Dowel, 1/2 Aluminum Angle or Thick Metal Bar will all work.

GRITS AND POLISH:
Picnic style plastic salt and pepper shakers that seal up are handy for course grits; they can be sprinkled on the mirror directly. Finer grits and polishing compounds are often pre-mixed with water in a suspension; here plastic squeeze bottles (also squeezed-style mustard containers) can be used effectively.
https://firsthanddiscovery.com/
Rough Grinding:
80 grit
120 grit
220 grit
Fine Grinding:
32, 20, 12, 5 micron grits.
Polishing:
Cerium Oxide.
Gugolz 64 Pitch.

BEVELLED EDGE:
The key item is a Sharpening Stone, often called a Carborundum Stone, used for sharpening knifes. You can buy a large stone in hardware, kitchen, sportsman or department stores.

MEASURING SAGITTA:
Metal Ruler
Feeler Gauge

MISCELLANEOUS:
Plastic Water Bucket for dunking your mirror and tool to clean off spent grit. Plastic is soft and won't chip your mirror. Do not wash grit down a sink - it will harden in your pipes and you will have to call the plumber.
Spray Bottle to spray water on your grit when you grind.
Red Laser Pointer

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BUILDING THE TELESCOPE
(rougher, to be done later when mirror is nearly finished)
-wood, teflon, hardware for the rockerbox
-aluminium tubing. 8" width, 6 feet length.
--OR sonotube. Easier to work with?
-secondary mirror. (and mirror spider?)
-black matte spray paint and sawdust for baffling.
-white primer for the outside. Either final gloss paint or something more creative?