I am an electronic enthusiastic. I made a lot of PCB. But most of them are the regular rectangular shaped. But I saw some custom designed PCB in most of the electronic equipment. So I try some custom designed PCBs in earlier days. So here I explain the making of a custom designed PCB. Here I use common tools for its preparation. Because, every electronic hobbyist do not have all the tools. So I use common tools here. This custom designed PCB is fully home made one. It help you to understand more about the PCB design. Here I use Instructables Robot as the PCB design and add some led illumination work to the PCB using SMD components. In the future steps I explain more about it. So lets go...
Here I use the SMD electronic components from old PCB. It reduce the project cost. You follow this method or purchase the components.
Copper clad
FeCl3 solution
PCB cleaner
All components are SMD
IC
Resistor
Capacitor
Led
DC connector
All component values are given in the circuit diagram.
The images are given above.
Here I use an dual op amp. IC. It is wired as an oscillator to produce low frequency oscillation to blink an LED. The 2 op amp. work independently and produce square wave signal. The two oscillator wired same manner to produce same signal. It is because otherwise we need to add a transistor to boost the current. Here it is not used because to reduce the complexity. So the LEDs drive by the 2 op amps. So current problem avoided. The circuit drawn in the 'spice' software. The circuit given above.
Here first I download the instructable robot image. Then covert it into drawn image by using image filters option in the Photoshop image editor. Then the images print into a paper for reference. The image size is same as the PCB size. This given as PDF file in below. Then I combine the robot image and the PCB design into a single image. This is used to mask the copper clad for etching. By this we get the circuit traces and the robot image in the copper clad. The images are given above.
In this step, we clean the PCB copper side by using the sand paper and reduce the thickness of the copper clad by using the sand paper and the file. The procedure given below,
Here in this step we apply masking on the copper clad for etching. The masking provide the circuit layout to the copper clad. This will avoid the etching at the masked portion. So the etching done only at the unmasked portion. By this made the copper tracks on the copper clad. The masking procedure given below,
Now the PCB layout is copied to the copper clad
It is the simplest method for creating the etching mask. Here we only use the permanent marker. It makes that, this method useful for any electronic beginner. In this way, we draw the layout in the copper clad by using the marker only. The steps are given below,
The etching is the removal of unwanted copper parts from the copper clad. By this method we create the circuit layout in the copper clad.The given procedure explain the etching process.
We need some hole to place the DC connector to it. This is the only through hole component in it. All others are the SMD components. It do not need any holes. For drilling I use a hand driller. Very small bit is used for drilling. Drilling starts from the copper side. Do not apply extra force. It will damage the PCB.
In this step I apply a coat of solder to the full copper traces like a mask. It will increase the beauty and it will protect the copper from corrosion. The copper react with water and air. So the solder will isolate it from the corrosion causing agents. For this First apply flux to the traces. Then make solder layer by using the micro soldering iron and solder wire. Then smooth it by using 25 W soldering iron. Then clean the PCB by using PCB cleaner solution.
Here we cut it into the Instructable robot shape. It is done by the ordinary tools like hacksaw blade, knife, file etc... The procedures are given below,
We done this step.
It is one of the main step in the PCB manufacturing. Here we check the continuity of each track with respect to the circuit diagram and check for unwanted short circuit.
Here I use the components from old PCBs. It will reduce the project cost and it will help you to study more about the electronics. This process increase our electronics knowledge. You choose this method or purchase the components. The de-soldering procedure shown in the above video. After the de-soldering, text the components using multi-meter and use it for this project and future projects. OK. Good luck.
This is the time for soldering. Here I use a micro soldering iron. First solder the IC and then the rest of the components. Do not apply extra heat. It will damage the IC. Solder the LED with care. Because it is heat sensitive. It will damage very quickly. The procedure is given below,
We done this step successfully.
Now it is the time for circuit testing and debugging. Connect a 9 V battery to it by using a male connector suitable for the PCB DC connector. If it is not blinking check the connections and the IC. Then check the LED. By completing the debugging section successfully, we get a good model of working Instructable robot.