While it is not necessary to use a machine to make a mirror, it can lessen the time it takes to do all the grinding and polishing. It is still best to make your first mirror by hand to understand how a mirror is made and works. You'll find pictures of the basic machine on this page plus one modification I've made which should help with figuring the final parabola into the mirror. I can attest to the machine's ability to grind and polish to a very smooth figure. I built mine from the plans that Dennis sells at his web site.
Members send in questions and observations about their machines and the group responds.
The two posts are for the table and the eccentric. The mirror rides on this table and may be either taped to the circular disk or wedged between three blocks as I do. Mirror centering is extremely important. The image to the right shows the bottom pulley and the dogs which keep the table and pulley turning together. The dogs also allow easy removal of the table from the machine for cleaning and adjustment of pulleys and belts.