What Every Hobbyist Needs to Know about the Etching Process of PCB Fabrication

What Every Hobbyist Needs to Know about the Etching Process of PCB Fabrication

Experts are often divided on the argument about which part of the PCB fabrication contains the highest level of difficulty. Some say that creating the schematic diagram is the most difficult because it requires a lot of attention to the smallest details. This process has been made easy by the availability of various programs that can be installed on a computer. These programs contain all the necessary tools that PCB fabricators can use to create diagrams.

However, some programs still require some manual polishing to ensure that the diagram is neat and the symbols are well-organized. The degree of polishing required for a computer-drawn schematic diagram depends primarily on its level of complexity.

Another part of the PCB fabrication process that people encounter some difficulty with is the process of etching the diagram onto the copper plate of the base board. One thing that can help PCB hobbyists in this respect is to use the PCB etching kits available in electronics stores. These kits often contain the basic necessities for etching, including:

1. Copper laminate

This is the most important part of the kit since it is where the circuit design would be printed on. This often consists of a thin sheet of copper foil that is laminated around several layers of fiberglass. The thickness of the copper laminate depends on the type of PCB that would be produced.

However, most starter kits for PCB fabrication often contain a standard-sized copper laminate that is large enough to create single-sided and double-sided PCBs.

2. Transfer Paper

This is useful in transferring the circuit design onto the copper laminate. The paper itself has to be made out of a material that is durable enough to stand the heat of a clothes iron. Some DIY PCB hobbyists have tried various types of glossy paper, such as the paper used on magazines or thick glossy photo paper.

These are good substitutes to the transfer paper on a starter kit. However, it is often better to just stick with the paper that came with the kit since the manufacturer would already have made sure that it is transfer-ready and durable.

3. Sealing Foil

This is useful in sealing the ink that has been transferred from the printing paper to the copper laminate. There are different types of sealing foils that can be used for PCB fabrication. The foil that comes in a PCB starter kit normally has instructions on how exactly the foil would work and in which type of etching process it would best be used on.

pcb fabricationMost PCB starter kits do not include the tools required to print the computer-drawn circuit design. For this purpose, hobbyists have to have a high-resolution laser printer. When printing using a regular laser printer, hobbyists have to make sure that the design they create on the computer program fits seamlessly onto a regular-sized printing paper. They wouldn’t consider this to be a problem if the circuit design is simple enough and contains only the basic components for PCB fabrication.

In order for the etching process to be completed, hobbyists also need several other supplies, such as:

1. A flat iron : Some long-time hobbyists have invested on an etching laminator since this is often safer to use than the flat iron.

2. Etching solution : The exact components of the solution vary according to what the hobbyist is most comfortable with, though the most commonly-used solution is muriatic acid or hydrogen peroxide.

3. A drill bit : This is useful in drilling holes onto the copper laminate according to the circuit design.

Once the etching process is finished, hobbyists can now focus on the fun part: mounting the components onto the homemade PCB.