Overview
Photochemical machining or etching is a manufacturing process to produce close tolerance, precision metal parts. It combines Computer Aided Design (CAD), photography, chemistry, and metallurgy. It can be used to create prototypes or production parts while avoiding hard tooling costs.
Dimensions and Tolerances
This section lists some general guide rules for determining results. Specific results vary depending on material and application. In general:
- A hole diameter can approach material thickness in thinner materials, however a hole diameter can never be smaller than material thickness unless reamed.
- The smallest outside radius is equal to 75% of the thickness of the metal. Under certain conditions, a radius smaller than a standard radius is achievable.
- The smallest inside corner radius is equal to the thickness of the metal.
- A tolerance of +/-15% of metal thickness is generally acceptable. On certain applications, a tolerance of +/-10% of metal thickness is achievable.
Materials and Alloys Commonly Etched
This section lists some commonly etched materials.
- Stainless Steel
- Alloy 300 and 400 Series
- 17-4
- 17-7
- 15-4
- Cold Rolled Steel
- 1008
- 1010
- 1018
- 1020
- 1075
- 1095 (blue clock spring)
- Copper and Alloys
- Copper
- Brass
- Phosphor Bronze
- Beryllium Copper
- Nickel Silver
- Nickel and Alloys
- Nickel
- Alloy 42
- Alloy 48
- Alloy 49
- Monel
- Kovar
- Inconel 600 Series
- Mu Metal, Hi Mu 80, Ad Mu 80
- Aluminum Alloys
- Most Alloys
- Other Metals
- Molybdenum
- Iron
- Metglas
- Solder Ribbon
- Beryllium Nickel
Thickness
Metal thickness from .0003" to .063" can be etched.