In recent decades, the materials available to the small scale electronics prototyper have not kept pace with the requirements of professionals. MG Chemicals has addressed this by releasing our new Professional Prototyping Process.

This process allows electronics engineers to prototype their own double-sided circuit board with plated through holes without having to send the design to a prototyping company.

It is also a valuable learning tool, because it mirrors the actual process used by contract manufacturers.

Some of the chemicals in this process pose significant safety hazards and disposal challenges, and for that reason this process is for professional use only. For amateurs and those making simple one sided boards, the MG Chemicals Basic Prototyping Process is more suitable.

These instructions assume the design of your circuit is completed, it a double sided board with through-holes, and you are ready to construct it.

There are 11 basic steps:
1. Cutting and Routing
The board is cut to size and routed to the desired shape.
2. Drilling, Deburring, and Reaming
The through-holes are drilled, the copper that lifts up on the opposite side is sanded smoothed ("deburred"), and refuse material is cleaned out of the holes ("reamed").
3. Electroless Copper Plating
A thin layer of copper is deposited on the inside of the through-holes using a five-step chemical bath system.
4. Resist Application, Exposure, and Development
Negative dry film resist is applied, exposed, and developed so that all of the copper that will be eventually etched off is covered by the resist, while the desired circuit and through holes are exposed for electroplating.
5. Copper Electroplating
The circuit and through-holes are plated with copper, making the through-holes usable.
6. Tin Electroplating
The circuit and through-holes are plated with tin, which will act as the etch resist, protecting the circuit when the unwanted copper is removed.
7. Resist Stripping
The resist is washed off with acetone or a sodium hydroxide solution.
8. Copper Etching
The board is placed in an sodium persulfate solution, which dissolves the unwanted copper but not the tin plated circuit.
9. Tin Stripping
The tin plating is removed (because it is very corroded after step 8).
10. Solder Mask Application
Solder mask is applied.
11. Electroless Plating of Connectors
Connecters are tin or gold plated using an electroless process.

View the complete Professional Prototyping Process manual

Training Videos:

Step 2: Drilling, Deburring, and Reaming
coming soon

Step 3: Electroless Copper Plating
Part 1: Introduction and cleaning the board
Part 2: Setting up the solution (part 1)
Part 2: Setting up the solution (part 2)
Part 3: Submerging the board

Step 4: Dry Film Resist Application, Exposure, and Development
Part 1: Overview, making artwork, safelight
Part 2: Resist application and exposure
Part 3: Resist development

Step 5: Copper Electroplating
Part 1: Introduction, calculating current, micro-etching
Part 2: Setup and electroplating

Step 6: Tin Electroplating
Part 1: Introduction, setup, tin electroplating

Step 7: Resist Stripping

Step 8: Copper Etching

Step 9: Tin Stripping