How to Make a Printed Circuit (with Pictures)

2024 Author: Samantha Chapman | [email protected]. Last modified: 2023-12-17 09:13

And so, you have a circuit designed and ready. You've done some computer aided simulations and the circuit is working fine. Only one thing is missing! You need to make a PCB of your schematic so you can see it in action! Whether it's a school / college project or the final part of a professional electronic device for your business, converting your circuit into a board will make it look a lot more professional, as well as give you a physical idea of that. that will be the finished product! This article will show you the different methods by which a Printed Circuit Board (PCB) can be created from an electrical / electronic schematic using different methods, suitable for small and large circuitry.

Steps

Step 1. Choose a method to use to create the PCB

Your choice will generally be based on the availability of the materials required by the method, the technical level of difficulty and the quality of the printed circuit board you wish to obtain. Here is a brief summary of the different methods and their main features that will help you decide:

1. Acid engraving. This method requires extreme safety measures, the availability of various materials such as the corrosive agent and moreover, it is a slower process than the others. The obtained quality of the PCB varies according to the materials used but, generally, it is a good method for circuits whose complexity ranges from simple to intermediate. Circuits that require denser wiring and the use of thinner wire connection tracks usually use other methods.
2. UV ray photoengraving. This method requires more expensive materials that may not be available everywhere. However, the steps are simple, require fewer security measures, and can produce more subtle and complex circuit layouts.
3. Mechanical engraving / routing. This method requires special machinery that will cut excess copper off the board or create empty separators between the connecting tracks. It can be expensive if you intend to purchase one of these machines and usually leasing them requires the availability of a nearby workshop. However, this method is good if you need to make multiple copies of the board and also produce thin PCBs.

4. Laser engraving. This method is usually used by large companies, but can be found at some universities. The concept is similar to mechanical engraving, but in this case, laser beams are used to carve the board. It is usually difficult to have access to such machinery, but if your local university is one of the lucky ones to have them, you may want to use its facilities if they allow it.

   

   Step 2. Create the PCB Layout of the circuit

   This operation is performed by converting the wiring diagram into the physical distribution of the physical components on a board, optimizing the spaces, generally using special software. There are several open-source software packages for creating and designing printed circuit boards, some are listed below to give you a starting idea:

   • PCB
   • Liquid PCB
   • Shortcut

   

   Step 3. Make sure you have collected all the necessary material according to the method you choose

   Step 4. Draw the circuit layout on the copper clad board

   This is only feasible in the first two methods. Further details can be found in the section on the in-depth analysis of the chosen method.

   

   Step 5. Engrave the card

   Read the sections of the "Specific Steps" to understand what the engraving processes are. It basically involves removing all unnecessary copper from the board, leaving only the connecting tracks of the final circuit.

   

   Step 6. Drill holes in the mounting points

   Usually, the drills used for this operation are made specifically for this purpose. However, with a few modifications, it is possible to use a normal drill to do the job even at home.

   

   Step 7. Mount and solder the electronic components to the board

   Method 1 of 2: Specific Steps for Acid Etching

   

   Step 1. Choose the etching acid

   Ferric chloride is a common choice as a corrosive agent. However, you can use ammonium peroxidisulfate crystals or other chemical solutions. regardless of which corrosive chemical agent you choose, it will still be a dangerous material; therefore, in addition to following the normal precautions mentioned in the article, you should also read and follow any further safety instructions related to the corrosive agent.

   

   Step 2. Draw the PCB layout

   For acid etching, you will necessarily have to draw the connection tracks using a material resistant to corrosive agent. If you intend to draw them by hand, you can find special markers to use for this specific task (not exactly ideal for medium and large circuits). However, laser printer ink is the most commonly used material. The steps to use laser printers for this purpose are:

   1. Print the PCB layout on glossy paper. Make sure the circuit is mirrored before proceeding (most PCB layout software have this option to print). This method only works if you are using a laser printer.
   2. Put the shiny side, with the print on it, in front of the copper.
   3. Iron the paper using a common iron. The time required depends on the type of paper and ink used.
   4. Soak the card and paper in hot water for a few minutes (up to 10 minutes).

   5. Remove the card. If certain areas seem particularly difficult to peel off, you can try letting it soak a little longer. If all went well, you will have a copper board with a PCB of pads and tracks traced with black toner.

      

      Step 3. Prepare the corrosive acid agent

      Depending on the type you choose, there may be further instructions. For example, some crystallized acids require dissolving in boiling water, while others are ready to use.

      

      Step 4. Dip the card in acid

      

      Step 5. Make sure you shake every 3-5 minutes

      

      Step 6. Remove the card and wash it when all unnecessary copper is dissolved

      

      Step 7. Remove the used insulation material

      There are special solvents available for almost all types of insulation materials used to make PCB tracks. However, if you don't have access to any, you can always use sandpaper (fine-grained).

      Method 2 of 2: Specific steps for UV Photoengraving

      

      Step 1. Draw the PCB layout on the special copper coated board

      

      Step 2. Cover with transparent foil (optional)

      

      Step 3. Put the card into the ultraviolet photoengraving machine / chamber

      Step 4. Turn on the machine for the time necessary to the specifications of the card and the machine itself

      Warnings

      • If you are using the acid etching method, you need to take the following precautions:

        • Always store your acid in a cool, safe place. Use glass containers.
        • Label your acids and keep them out of the reach of children.
        • Do not dispose of used acid in household drains. Rather, set it aside and when you have enough, take it to a recycling and hazardous waste disposal center.
        • Use gloves and air masks when working with corrosive acids.
        • Be extremely cautious when mixing and shaking the acid. Do not use metal objects and do not put the container on the "edge of the disc".