PHOTO CHEMICAL
MACHINING PROCESS

The Photo Chemical Machining process has 9 essential steps to achieve simple or complex thin-metal components of one to one million parts. This is a very economical option for research and development or prototype phase of a project when quick turnaround is vital. Our PCM process is used to etch through metal thicknesses between .0005″ to .060″ and between .060″ to .250″ for depth etching on metal only.

  1. Engineering Support
  2. CAD/In house plotting
  3. Tooling
  4. Metal Preparation
  5. Exposure
  6. Developing
  7. Etching
  8. Stripping
  9. Inspection

Northwest Etch Photo Chemical Machining

1. ENGINEERING SUPPORT

Our Engineer is available to assist in designing your product for the best Photo Chemical Machining results including which alloy material best suits your product for form, fit and function.

  • Provide low cost prototypes
  • In house forming

2. CAD/IN HOUSE PLOTTING

Our Full-Time Graphics and CAD Lead can help you with:

  • Drafting
  • Artistic capabilities
  • Decorative projects
  • In-house plotting (1/8 mil plotting up to 24″ x 24″)
  • Outsource plotting (oversize up to 60″ x 80″)

3. TOOLING

Our Tooling is unique to your individual part and is stored in our in house library:

  • Standard size tooling is 12 X 24 inches
  • Custom size tooling is available

4. METAL PREPARATION

Is the process for surface preparation and cleaning of the metal to enhance adhesion for photo sensitive film that is acid resistant. Types of surface preparation are:

  • Pumicing
  • Scotch Bright
  • Brushing
  • Laminator capabilities up to 60 inches

5. EXPOSURE

Photo tool and laminated metal are exposed to white light leaving photo tool image on the laminated metal. Standard size 12 X 24 inches up to 60 X 80 inches

6. DEVELOPING

Exposed metal is put through a potassium carbonated wash which washes away unexposed photo resist.

7. ETCHING

The etching process is a controlled method of removing the exposed metal left behind by the developing process.

  • Up to 60 inch wide material

8. STRIPPING

A caustic solution is used to remove the remaining resist from the metal

9. INSPECTION

The C=0 Sampling Plan is used to determine the number of parts that are dimensionally inspected. The sample size is based on the number of parts and the historical level of confidence regarding the part acceptability. Generally, the parts are presented to Inspection in sheet form. Parts are checked in the four corners and in a zig zag pattern throughout the sheet. If one part is rejected, the parts surrounding the scrapped part are checked until we are confident that there are no more out of tolerance parts in the sheet. When parts are given to Inspection as pieces, a sample size is determined using the C=0 Sampling Plan. If one part is rejected, the entire lot is checked. Breaking the parts out of the sheet and packaging for shipment is a critical role of the Inspector. This presents an opportunity to visually inspect the parts and assess cosmetics.

Sampling Plan

FIRST ARTICLE INSPECTION

CERTIFICATION PROVIDE BY NW ETCH

  • Certificate of Conformance (NW Etch Packing List)
  • Specialized Certifications as required by customer
  • Metal Certification

SERVICES CERTIFICATES

  • Forming, Plating, etc.
  • All products are evaluated before and after services work.
  • Records are maintained as required by ISO guidelines.

INSPECTION AND TEST EQUIPMENT

  • Calipers
  • Micrometers
  • Depth gage
  • Pin gages
  • Surface plates
  • Surface profilometer
  • Optical Gauge Product Machine

Calibration is maintained on all inspection tools. Training records are maintained on all staff. Inspection stamps are issued after initial training is completed and documented. The inspection stamp number is based on the employee number and is therefore, unique. When an employee leaves the company, the stamp is pulled and the number retired.