How to Make PCB at Home
PCB or Printed Circuit Boards are used to electrically connect and mechanically support several different electronic elements using conductive tracks, signal traces, and pathways, which are etched from copper sheets that are laminated over a non-conductive substrate. Components are then connected through the conductive material beneath a non-conductive board. Since copper is a cheap metal, the conductive material used in PCBs are commonly copper.
PCB is used in almost all electronic products. Many prefer using customize PCB than the ready-made ones for many reasons. First, a customized PCB will be more compact as you have designed it well to make it compact. Second, homemade PCB is more convenient to use, as you are the one deciding the space needed on your board. And last, the board you have made will be stronger, unlike the ready-made PCBs that have more number of holes, which makes them weaker.
Making a Printed Circuit Board is quite easy, but for beginners, it can be challenging. Here is a complete step-by-step guide for making a printed circuit board at home.
Step 1: Assemble the Necessary Tools and Materials
You must have all the tools and accessories that you need to be assembled on your workbench so that you can do your project in an organized way. Given below is the list of items that you’ll need in making a customized PCB:
- Ø Mini Drill for drilling holes in your circuit board.
- Ø Flat Iron for transferring the circuit design onto your substrate.
- Ø Desktop computer with a decent PCB designing software to create your circuit design.
- Ø Laser Printer or Photocopying Machine for printing out the PCB design.
- Ø Latex Gloves for hand protection.
- Ø Safety goggles for eye protection.
- Ø Etching Solution, such as Ferric Chloride
- Ø PCB card
- Ø Marker with a fine tip
- Ø Ruler
- Ø Magazine Paper or Glossy Paper
- Ø Plastic Tweezers or plastic Straws
- Ø A small piece of cotton cloth
- Ø Sand paper
Step 2: Create the PCB Layout
Before making your customized PCB you must first design its layout on your computer. You can use a decent circuit board designing software to create your own PCB layout. The Eagle Layout Editor is a very good option for experts, but if you are looking for a less complicated editor than you can use Microsoft PowerPoint.
Step 3: Print the Layout
Now that you are done with designing the layout, you’ll have to print it out. For printing, you can either use a Laser Printer or a Photocopying Machine. If you are thinking about using an Inkjet printer, it wouldn’t work because its ink is soluble in water, and won’t be transferred onto the PCB board. You can use a glossy paper or magazine paper.
Step 4: Align and Iron
Cut out the PCB card according to the size of your layout and align the paper carefully over the board, with the print on the downside facing the board. Start up the iron and set it on the cotton setting and allow for it to heat up. if the paper is thick you should set its temperature to the highest setting, but if not, simply set it to medium setting. Once your iron has heated, carefully place it on the paper on top of the copper board and let it be for 35 to 40 seconds. The heat from the iron will melt the ink printed on the paper and get transferred to your copper plate.
- Ø The board is going to heat up rapidly so hold one end of the board by the cotton cloth or towel.
- Ø Pay more attention towards the edges of your board.
- Ø You must apply sufficient pressure.
- Ø Do the ironing slowly and don’t make any crease in the paper.
- Ø A long hard press works better and is safer than moving the iron around.
Step 5: Peel off the Paper
After the ironing is done, now remove the iron from the board and place the board in a container of water for two to five minutes. Alternatively, you can also gently rub it while you expose the board to running tap water. Before rubbing off the paper make sure that the paper on the board has become mushy so the ink won’t be removed while you do that. Get the water off by wiping the board with a napkin. Don’t rub vigorously; else the ink on the board may come out.
Step 6: Saw the Access Board and Restore
Cut off the excess PCB card with a metal saw, if any. To smoothen the edges use a sand paper. To have a finer finish you would want to use a finer sand paper.
Even though you may have rubbed the paper off, there still may be some paper residue left on your board. Check carefully and remove it using a sharp object such as the tip of a cutter, a tooth pick, or point of a sharp compass. While rubbing it off or sawing the extra board, the ink in some areas may have been removed unintentionally, so you should restore the areas using a ruler and a marker.
Step 7: Etch the Board
Now that you are ready with the board, it’s time to etch it. Etching removes any unwanted copper from the PCB and only leaves the wiring necessary for the final circuit.
Choose the Method and Etch
There are two common processes preferred by most DIY PCB makers; Acid etching or UV etching. You can choose any of the two methods for creating the PCB. Your choice depends on the availability of materials needed for the process, the difficulty level or the quality of board you want to obtain.
In this, you’ll need an acid to etch the PCB. the extreme safety measure is necessary for this process. You’ll need many materials such as the etchant and this method is somewhat slow. The quality of board obtained will vary according to the materials used but generally, it’s a good process for a simple to intermediate level of circuit complexity. Circuits that involve tiny wires and more close wiring usually need other methods.
Steps of Acid Etching
- First, you should choose etchant. Ferric chloride is preferred by most. However, you can also use Ammonium Per-sulfate crystals or any other chemical solution that you may find suitable for your project. No matter whatever chemical you choose, it’s always a danger, so besides following your own safety measures, you must also read and strictly follow the additional safety instructions that come with the specific etchant.
- Then you must prepare the acid etchant on a sturdy and non-metallic container. Depending on the chemical that you are using, there might be some additional instructions. For instance, some crystallized chemicals must be dissolved in hot water, while other etchants come ready to use.
- Now submerge the PCB in the solution for at least 30 minutes and make sure that you stir it every 3 to 5 minutes. Also, check in every 5 to 10 minutes if the PCB is etched or not.
- Use non-metallic pliers to take the board out and check if the entire unmasked area is etched properly. In case it’s not etched leave the PCB in the solution for some more time.
- After the unwanted copper has been entirely etched from the PCB now wash the board in running water.
- Finally, remove the drawing material used on the PCB. There are specially formulated solvents available in the market for almost all sorts of material used in drawing the PCB layouts. However, if you don’t have any type of solvent, then a fine sand paper is always a great option.
Etching with Ultra-Violet Transposition
For this method, you’ll have to follow a totally different procedure from the very beginning, than the one mentioned above. this process is used for transposition of the PCB layout onto the PCB board. It requires more expensive materials that may not be available in many places. However, the procedure is relatively simple and you can obtain finer and more complex circuit layouts.
For this method, you’ll need a photosensitive laminated PCB card, distilled water, a UV insulator and a transparent sheet. There are many ready to use cards available that are coated with black nylon layer. Else you can use a photosensitive spray to apply on the copper part of a standard blank PCB card. You’ll also need to purchase a photo-revelator compatible with the PCB photosensitive coating or the photo spray.
- Draw the layout of your PCB on the transparent sheet, either in positive or negative mode, depending on the photosensitive coating of the PCB card.
- Cover the copper side of the card with the layout and place the PCB in the UV insulator device.
- Now turn on the UV device. The insulator will irradiate your PCB card with the UV for the desired amount of time. Many UV insulator devices have adjustable timer. Generally, 10 to 20 minutes of irradiation is widely sufficient.
- When done, remove the PCB card from the UV chamber. Use the photo-revelator to clean the copper part of the PCB. Now gently rinse the PCB card with distilled water before placing in acid bath. The acid will etch the parts destroyed by the UV.
- For the acid bath, you can follow the same steps applied in acid etching.
Some of the most basic safety measures that you must follow while etching:
- Ø Always store your chemical in a safe, dry and cold place. Only use glass containers to store.
- Ø Label your etchant and store it out of the reach of children.
- Ø Do not dispose of your used etchant in the home drains. Instead, you can store it and when you have a good amount of used acid, take it to your nearest recycling center or harmful waste disposal facility.
- Ø Use air masks and gloves when working with the acid. Always wear safety goggles when etching and never look directly into the mouth of the chemical container.
- Ø When stirring or mixing the acid you must be extremely careful. Never use metallic objects and put the acid container on the edge of your workbench.
- Ø While using the UV method, be very careful not to have a direct visual contact with the radiating part of the UV insulator. To avoid this you can use a special UV protection glasses. And in case you need to check your PCB during the irradiation process, better stop the machine before opening it.
Step 8: Drill the Holes
Your final step is to drill the holes or mount points. You can use a mini drill for drilling the PCB. The copper layout will guide you, so make sure you drill on the copper side. Check the board carefully so that you don’t miss any point. After the drilling is done rinse it again with water and dry it using a piece of cloth.
Now that you know every step of making your own PCB, you might be thinking that this task is not very complicated after all. It’s very simple and you can create a perfect PCB at home if you carefully follow the procedures. I would only suggest you be organized and careful about your own personal safety.