DIY - Dual Layer PCB Making

by Pratik Makwana

12K11015

Intro: DIY - Dual Layer PCB Making

In this instructable, I will show you how to make dual layer PCB. I'm using this method for etching of the dual layer circuit boards at home.

What things you will need:

  • Copper - clad board

  • Ferric Chloride (FeCl3)

  • Acetone (Nail polish remover)

  • Glossy Paper
  • LASER Printer
  • Marker Pen

  • Scissors

  • Adhesive tape

  • Plastic container

  • Sand paper

  • Safety gloves

  • Saw - For copper board cutting

Let's Do it...

STEP 1: Designing of the Circuit

Design schematic diagram in EDA tool (PCB Design Software).

List of EDA Tools (PCB Design Software):

You can select any one of them.

I prefer EAGLE PCB Design Software.

STEP 2: Designing of the PCB Layout

After designing of the schematic diagram, Now start designing of PCB Layout in the Eagle EDA tool (PCB Design Software). After that Take print out of PCB Layout on glossy paper.

Note: Use Only LASER printer only.

Remember, Before top layer printing. You need to mirror image of the top layer layout. otherwise, The circuit will be inverted..

Note: Scale Factor set to 1.

STEP 3: Cutting of Copper Board

Cut the copper board according PCB layout size. After cutting the paper, put this top layout on the top side of the PCB. Now put bottom layout paper on the bottom side of the PCB.Use adhesive tape to stick the paper on copper board.

STEP 4: Toner Transfer Method

Use an iron to transfer the toner on the glossy paper to the PCB.Make sure your copper board is as clean as possible. Now start ironing on top side of copper board. After 2 to 5 minutes start ironing on bottom side of copper board (Approximate 2 to 5 Minutes).

For the toner transfer method, required temperature is 210 C (410 F). So set the iron temperature to its maximum value. After ironing, Now start peeling off the paper with tap water.

STEP 5: Etching Process

Before you start etching, check all the tracks. If any track broken, use permanent marker pen to draw a track with carefully. Use ferric chloride (FeCl3) as etchant. Get you ferric chloride(FeCl3) powder and mix with water in your plastic container.Now start to etching of PCB.

After etching process, use the acetone to clean it.

STEP 6: Drilling Process & Soldering Process

After cleaning of PCB. Now start drilling of copper board. After Drilling, Start soldering process.

STEP 7: Testing

After soldering, Start testing the circuit.

Job Done!

14 Comments

TimF96 11 months ago

If you want to use a IC socket or a pinheader (SIL type 0.1" pitch connector), use the onees that is purpose designed for wire-wraping.

JamesW440 6 years ago

It is not wise to use oil on PCBs. The material is relatively soft and drills very easily - though the drill bit wants to wander. To avoid that, use the etched board with etched 'holes' where the holes are supposed to be. The etched holes serve as guides for the drill bit and for locating the hole. The smaller the etched hole, the easier the drill will start in the correct spot - your error tolerance will be the difference between the bit diameter and the etched hole diameter.

I have found that drilling with an ordinary (though somewhat unwieldy) drill press works well using ordinary high speed (HS) drill bits. The carbide kind are better, but a bit harder to find and a bit more expensive. I bought 10 carbide bits one each from 0.3 to 1.2 mm for about $4. I bought 10 HS 0.9 mm bits for less than $2.

The trick is to get the drill press to run as fast as it can - the speed on my press is maxed at 3000 rpm. But set at 3000 rpm, I was able to drill over 500 holes in short amount of time. The main thing is that if the drill bit turns too slowly, you will begin to overheat the plastic so that it melts and grabs the bit. Then 'snap'! At the faster speed, it will operate better without heating as long as you lift the bit out of the hole to allow it to clear periodically. Using the carbide drill bits, I did not experience that problem as they would 'chip' the material rather than cut it. They also were hard to get started at the point that I wanted because they would bend the drill bit shank enough to allow it to start the hole in the wrong spot.

I used a piece of plastic cardboard under a fairly dense foam about 1/8" thick each as the support that rested on the drill press pad with the PCB unrestrained on top (I held it in place as needed by hand). As I neared the max thickness that the bit would drill, I pulled it up so it would clear itself and then returned the bit to drill through the rest of the hole. As it goes through the bottom of the PCB, it will lift slightly so you know that you can lift the bit out of the hole.

I have successfully drilled thousands of holes in 1/16" and 1/32" material without problems other than if I tried to stay at speeds lower than 400 rpm or so, where the plastic melted and 'grabbed' the bit which broke the bit. I used only 3 HS bits to do over 1500 holes in about an hour total drill time; one due to grabbing and two due to stupidity (moved the PCB before the drill bit was out of the way).

I will reiterate that the carbide tipped drills work better at 3000 rpm and the cost is not that much more than ordinary HS drills, however, the HS drills work well enough. I used 1/32" and 0.9 mm drill bits for the small holes usually (0.7 mm also works fine for small holes) up to 1.2 mm bits for larger holes.

I also have a Dremel tool, but no drill press guide for it. I did a couple of holes using it, but was unable to get them to start at the correct point - plus I am not steady enough.

pcbwiz 6 years ago

Thanks for the reply JamesW440. Since then, I have my drill press setup and have been doing a lot of drilling not using oil... Maybe for drilling metal, but for PCBs, no oil required.

PraneethC6 7 years ago

I didn't find ATTiny85 in Eagle PCB software..

Could someone help me..?

Pratik Makwana 7 years ago

Hi,

Please Download ATTiny85 library for Eagle PCB Software.

Click Following link..

ATTiny85

After downloading the .zip file, unzip that file. Now copy .lbr file to lbr folder. This lbr folder located in Eagle PCB software installed directory.

If you want download more library for Eagle PCB Software, Go to this web page..

DIYmodules.org

Thank You.

PraneethC6 7 years ago

Instead of using LASER printer , can I use any other alternative....?
I didn't find LASER printer nearer to me..!
Please reply to me asap...!

I am a beginner in building PCBs...

Pratik Makwana 7 years ago

This toner transfer method only works with LASER printer. This method won't work with Inkjet printers. You can use copier machine for this method. You can find this copier machine at copier shop.

Find a copier shop nearer to you. Take a print out on glossy paper and follow the above steps.

List of copier machines:
1. xerox copier machine
2. canon copier machine
3. HP copier machine
4. Konica Minolta copier machine

For better result Go for the Konica Minolta (KM) copier machine (If available).

Remember two things for the copier machine,
1. Set the darkness to maximum value for better result.
2. Scale factor set to 1 for copier machine.

gm280 7 years ago

I've built tons of PC boards. And for the most part I do the same techniques as well. However, I use a product called P-N-P Blue. It is put out by Teckniks. It stands for Press-aNd-Peel Blue transfer film. I have tried ever type transfer that there is and the PNP Blue is by far the best I ever used. It isn't very costly and does work better then gloss paper. You posted a nice project. Thumbs Up!

jphicks 7 years ago

I have used the P-N-P Blue as well and it works well. I have stopped using ferric chloride as my etchant. Too much trouble in trying to dispose of and messy as well. I now use one part muriatic acid to two parts 3% hydrogen-peroxide. Disposal is easy just flush the used mixture down the toilet. Muriatic acid is often used as a drain cleaner anyway.