Photo Chemical Machining is accomplished by selectively masking the metal, then spraying with an acid. As the droplets of acid impinge on the metal erosion occurs. This process removes metal without creating burrs and does not work harden the material. Other advantages are that most metals can be processed by Photo Chemical Machining, and the temper has no bearing whatsoever. Photo Chemical Machining does have unique characteristics that must be considered to achieve the optimum results. Some of these are presented here, but it would be prudent to contact your Vaga Industries representative if in doubt.
UNDERCUT - As the acid droplets impinge on the metal and begin
to cut through, a certain amount of side erosion occurs. This is referred to as undercut and is the main factor governing the tolerances
that can be held. As the thickness increases so does the undercut,
and in turn so do the tolerances that can
MATERIAL WIDTH BETWEEN HOLES AND METAL THICKNESS - The metal thickness puts limitations on the material width between holes. Minimum widths are shown in Table 1. Also see Fig. 2
| Table 1 | |
|---|---|
| Thickness | Spaces between holes (w) |
| less than .005" | At least metal thickness |
| Over .005" | At least 1.25 times metal thickness |