Make your own Printed Circuit Board at home

Believe me it’s not that tough :)

When we start working with electronic components we face many problems with messy breadboard and Vero boards  though for smaller circuits they are best but as we move to some larger circuits we start facing problems. PCB is the best solution for these problems and also they are very handy, we can easily place our PCB on our bot without fear of short circuit or loose connection. But PCB is tough and costly to get manufactured from any commercial PCB company. 1500-2000 bucks can easily be saved if we do it at home.

Few days ago I thought of making one PCB and suddenly my friend Aniket told me about his project on chemical machining and there I got the initial spark for my work.

Printed Circuit Board can be made from components available in market or can be easily bought online. We will be using Chemical Etching method to make our PCB board.

Components required

• 1.      Copper Board ( FR 4)
• 2.      FeCl₃  (anhydrous)
• 3.      Drill
• 4.      Glossy Paper
• 5.      Pointed permanent marker.
• 6.      Laser Printer
• 7.      Cloth pressing Iron

These items can be bought online; I saw them on www.onlnetps.com , www.probots.com

Paper must be glossy, photo paper will be best but I feel any glossy paper will work.

The design which I made is a development board for ATmega32/16. The board is single sided that means circuit tracks are made on only one side of the board.

We first design our circuit using any circuit designing software like Eagle (CADsoft) or DipTrace. We must take care of the footprint of the component we use. Footprint here refers to exact shape of the component.

To get our PCB we must transfer the design to copper board but it is tough to do it directly as we cannot pass the board through the printer : P, so we have to look for another way to do it. We do it by transferring it with help of paper. We print mirror image (as we are concerned with the bottom of the final design) of our designed circuit on glossy paper. Please take print in high definition mode of the printer (Do not go for toner saver mode). USE ONLY LASER PRINTER TO PRINT THE CIRCUIT.

Mirror Image of the Circuit

Image on glossy paper

For BIT Mesra you can check Mishra Xerox, Mishra Ji was very helpful in my case (he has always been throughout our college life :))

So we have the image with us now printed on a glossy paper using a LASER PRINTER in high definition mode. It’s time to transfer it on our copper board. To transfer the image from paper to copper, we place the paper with circuit on copper board such that both the printed side and the copper face each other. Fix the paper on board such that it do not move, I used cello tape for this purpose.

Copper Board

Keeping glossy paper on copper board.

After confirming that the paper won’t move, place hot Iron on the paper and press it hard. Keep doing this for 5 to 10 minutes so that the toner melts and stick on the copper board. The paper must be pressed uniformly every side so that image gets transferred properly. Slowly remove the paper, yay!! We got our image on the board but this time the mirror image of the image on paper (remember I said to print mirror image on paper) so finally we get the desired image on our copper board.

Using Hot Iron to press the image and copper plate

If pressing is done properly the complete image will be transferred. If not don’t worry still we can correct it. Use pointed permanent marker to reconnect the broken tracks and mend pads. So we end up here with a copper board with circuit image (scientifically maskant) on it.

Impression of the image on the board

Tracks mended using permanent marker

Now it’s time to prepare Fecl3 solution. Concentration of FeCl3 should be 25 -30% by weight, there must be enough solution so that the board gets immersed completely in it. As water and FeCl3 reacts exothermically add FeCl3 to water slowly, do not add water to FeCl3. Please be careful about the preparation of the solution. Use any non-metallic container to prepare the solution. When the solution is ready, put the board in it slowly and keep agitating the solution. FeCl3 reacts with copper and copper erodes, due to this process unmasked copper gets removed and places where toner or marker’s ink was present get left unaffected. Keep checking the board at small interval of time; it took about 15 minutes in my case to decompose all copper from the board.

Putting Board in the solution

Half etched copper board

almost done :)

Board after etching

finally its here :)

 I failed first time, but I did it again and got the complete board, don't worry if it does not come out to be correct. Try again you'll get fully finished board 

Bingo!! We have now a board with complete circuit on it, just clean up the board, drill holes according to design. So we now have a PCB, solder your component and start your project :).

I said it’s not that tough.

Precaution

•  FeCl₃ is corrosive so avoid contact with eye or skin.
•  FeCl₃ act on your cloth too, avoid spilling the solution or FeCl3 on your cloth if you want to wear them again.
• Please wear glasses and gloves before trying it.

Note: The reader should understand the risk so please be careful while manufacturing, The blogger has done it carefully and is not responsible for any damage or loss.








Do comment if you like or any suggestion that can make this blog more helpful :)