Introduction: DIY PCB Etching Machine

About: Electrical engineer by profession

Hello friends in this video I have built a PCB etching machine.

this machine used or chemical treatment of Copper clad PCB


first black spray paint on blank copper clad PCB, then I trace the PCB track using Laser machine.

Then I dip this PCB in solution off ferrous chloride and here this machine came in picture, this machine continues to shake PCB so that exposed copper evenly dissolve in the solution.



Supplies

  1. 12mm wooden sheet
  2. M6 threaded rod
  3. M6 dome nut
  4. DC motor speed control PCB
  5. DC gear motor
  6. Motor clamp
  7. some plastic parts
  8. Plastic tumbler
  9. Ferrous chloride power
  10. PCB to etch

Step 1: What Is PCB Etching

PCB etching refers to the process of removing unwanted copper from a printed circuit board (PCB) to create the desired circuit pattern. PCBs are typically made of a substrate material, such as fiberglass, with a layer of copper laminated onto the surface. The copper layer forms the conductive pathways that connect the electronic components on the PCB.


The PCB etching process involves selectively removing the copper from the board, leaving behind the copper traces that form the electrical connections. Here's a general overview of the PCB etching process:


1. Design the PCB:

  - Use PCB design software to create the layout of the circuit, including the traces and component placements.


2. Transfer the Design to the PCB:

  - Print or transfer the circuit design onto the PCB substrate. This can be done using various methods, such as using a laser printer and transfer paper or using a photosensitive film.


3. Apply Etch-Resist:

  - Protect the areas of the PCB where you want to keep the copper traces. This is often done by applying an etch-resistant material (e.g., photoresist) to the entire board, exposing only the areas that need to be etched.


4. Etching:

  - Immerse the PCB in an etching solution, typically an acid (e.g., ferric chloride or ammonium persulfate). The acid removes the unprotected copper, leaving the desired circuit pattern.


5. Remove Etch-Resist:

  - After etching, remove the etch-resistant material from the PCB. This can be done by washing the board with a suitable solvent.


6. Clean the PCB:

  - Rinse and clean the PCB thoroughly to remove any remaining etching solution or residues.


7. Drilling and Finishing:

  - Drill holes for component leads and mount the electronic components on the board. Additionally, add any necessary finishing touches, such as a protective coating.


It's important to follow safety precautions when working with etching solutions, as they can be corrosive and potentially harmful. Additionally, proper disposal methods should be used for the chemicals involved in the process. PCB etching is a common method for prototyping and small-scale production of electronic circuits.

Step 2: Method

Design the Frame:

  • Plan and design the wooden frame to hold the various components. Ensure it provides stability and accommodates the size of the PCBs you intend to etch.

Build the Wooden Platform:

  • Create a wooden platform that can move up and down. This will hold the etching solution bucket. Attach the DC gear motor to the platform, ensuring it is securely mounted.

Assemble the XY Table:

  • If your design includes an XY table for precise movement of the PCB, assemble it according to your plans. This table should allow for smooth motion in both the X and Y directions.

Attach the DC Gear Motor:

  • Mount the DC gear motor on the wooden platform, ensuring that it is aligned properly. The motor will be responsible for raising and lowering the etching solution bucket.

Custom PCB for Motor Speed Control:

  • Design and fabricate a custom PCB for controlling the speed of the DC motor. This PCB should incorporate a motor driver circuit and a speed control mechanism. Connect the PCB to the DC motor using appropriate wiring.

Connect Power Supply:

  • Connect the power supply to both the DC motor and the custom PCB. Ensure that the voltage and current ratings are suitable for the components.

Testing:

  • Test the motor speed control by varying the input to the custom PCB. Make sure the DC motor responds accordingly, adjusting its speed as desired.

Safety Precautions:

  • Implement safety features such as a splash guard around the etching solution bucket and ventilation to mitigate fumes. Ensure the machine has emergency stop functionality.

Fine-Tuning:

  • Fine-tune the machine's movement and speed control to achieve the desired etching results. Make any necessary adjustments to ensure accuracy and reliability.

Assembly:

  • Assemble all the components onto the wooden frame, ensuring a secure and stable structure. Double-check all connections and fastenings.

Final Testing:

  • Perform a comprehensive test of the complete PCB etching machine. Verify that the motor speed control functions correctly and that the wooden platform moves smoothly.

Safety Gear and Environment:

  • Ensure that the operator wears appropriate safety gear, such as gloves and goggles, and that the workspace is well-ventilated to handle the etching process.

Keep in mind that this is a simplified guide, and the design may need adjustments based on the specific requirements and dimensions of your DIY PCB etching machine. Always follow safety guidelines and exercise caution when working with chemicals and machinery.





Step 3: CUSTOM PCB

Design of Custom PCB for DC Motor Speed Control


In this project, a custom PCB has been meticulously designed to offer precise control over the speed of a DC motor. The heart of the control system lies in the integration of a 555 timer IC (Integrated Circuit) and a TIP122 Darlington transistor.


Components Used:

1. 555 IC:

The versatile 555 timer IC is employed as the pulse width modulation (PWM) generator. Its astable mode configuration allows it to produce a continuous square wave output, the duty cycle of which is controlled by an external potentiometer.


2. Potentiometer:

A potentiometer serves as the user-controlled input, allowing for the adjustment of the reference voltage supplied to the 555 IC. This reference voltage determines the duty cycle of the PWM signal, thereby regulating the speed of the DC motor.


3. TIP122 Darlington Transistor:

The TIP122 acts as a robust and high-gain amplifier for the PWM signal generated by the 555 IC. Its ability to handle relatively high currents makes it an ideal choice for driving the DC motor.


Working Principle:

1. Potentiometer Input:

The potentiometer provides a variable voltage reference to the 555 IC. By turning the potentiometer, the user can set the desired speed for the DC motor.


2. 555 IC PWM Generation:

The 555 IC is configured in astable mode, producing a continuous square wave output. The duty cycle of this PWM signal is determined by the voltage received from the potentiometer.


3. TIP122 Amplification:

The PWM signal generated by the 555 IC is then fed into the base of the TIP122 Darlington transistor. The TIP122 amplifies the PWM signal and controls the current flow through the DC motor accordingly.


4. DC Motor Control:

As the duty cycle of the PWM signal changes, the TIP122 modulates the power supplied to the DC motor. This dynamic control mechanism allows for smooth and precise adjustments to the motor speed.


Advantages of the Design:

- Fine Speed Control:

The use of PWM allows for fine-tuned control over the speed of the DC motor, providing versatility in various applications.

- Cost-Effective:

Leveraging common components like the 555 IC and TIP122 transistor ensures a cost-effective design without compromising performance.


- Reliability:

The TIP122 Darlington transistor, known for its reliability and high current capability, enhances the robustness of the motor control system.


In conclusion, this custom PCB design effectively marries the time-tested 555 IC and the TIP122 Darlington transistor to create a reliable and efficient DC motor speed control system. The integration of a potentiometer adds user-friendly adjustability, making it suitable for a wide range of applications requiring precise motor speed modulation.



Discover Excellence with JLCPCB.com for Your PCB Needs!

Embark on a journey of precision and reliability with JLCPCB.com, your go-to destination for top-notch PCB solutions. At JLCPCB, we bring you the perfect blend of high quality and affordability, ensuring that your PCB needs are met with excellence.

Why Choose JLCPCB?

  1. Unparalleled Quality: Our commitment to quality is unwavering. Experience PCBs that meet the highest industry standards, crafted with precision and care.
  2. Affordable Rates: Quality shouldn't break the bank. JLCPCB offers competitive and pocket-friendly rates, making top-tier PCBs accessible to everyone.
  3. Versatility: Whatever your project demands, we've got you covered. JLCPCB provides a range of services tailored to your needs, from standard PCBs to advanced offerings.
  4. Swift Turnaround: Time is of the essence, and we understand that. Benefit from our fast and efficient turnaround times, ensuring your projects stay on track.
  5. Comprehensive Services: JLCPCB goes beyond PCBs. Explore our additional services, including 3D printing and metal CNC, to bring your ideas to life with unparalleled precision.


Whether you're a seasoned professional or a passionate hobbyist, JLCPCB.com is your trusted partner for bringing your electronic designs to fruition. Join countless satisfied customers who have chosen JLCPCB for their PCB needs.

Visit JLCPCB.com today and experience the perfect synthesis of quality, affordability, and innovation. Your projects deserve the best – choose JLCPCB for excellence that goes beyond expectations!


If you want to order the same PCB I have used in this project so you can download PCB files from the link

https://drive.google.com/file/d/10GNT80hahipvUGRRnu6U1uAicV74jcg0/view?usp=sharing

Step 4: PCB Etching Solution

PCB Etching Solution Using Ferric Chloride and Water:


PCB etching is a crucial step in the fabrication of printed circuit boards, and the etching solution plays a key role in selectively removing copper to create intricate circuit patterns. One commonly used etching solution is made by combining ferric chloride (FeCl3) with water. Below is a brief note on the characteristics and usage of this solution:


Composition:

The etching solution consists of ferric chloride, a compound composed of iron and chlorine, dissolved in water. Typically, the concentration of ferric chloride in the solution can vary, but a common ratio is around 40% ferric chloride to 60% water.


Characteristics:

1. Corrosive Nature: Ferric chloride is known for its corrosive properties, making it effective in etching copper from the PCB surface.

2. Dark Color: The etching solution often has a dark brown or orange color, reflecting the presence of ferric ions.


3. Temperature Dependency: The etching process is temperature-dependent. Higher temperatures generally accelerate the etching reaction, but excessive heat can lead to undesirable side effects.


Usage Instructions:

1. Safety First: Prioritize safety by wearing protective gear, including gloves and goggles, as ferric chloride is corrosive. Work in a well-ventilated area or under a fume hood.


2. Preparation: Mix the ferric chloride with water in the appropriate ratio. Use a non-metallic container, as metals can react with the solution.


3. Immerse the PCB: Submerge the PCB into the etching solution, ensuring that the copper side faces down. Agitate the solution gently to promote even etching.


4. Monitoring: Regularly inspect the progress of etching. The solution turns a clear greenish color as it reacts with and dissolves the copper. The time required depends on factors like temperature and the concentration of the etchant.


5. Neutralization: Once etching is complete, carefully remove the PCB and neutralize the remaining ferric chloride by rinsing the board with a solution of baking soda or a similar neutralizing agent. Dispose of the neutralized solution responsibly.


6. Cleaning: Thoroughly clean the PCB to remove any remaining etchant residue. Isopropyl alcohol is often used for this purpose.


Advantages:

1. Effectiveness: Ferric chloride is highly effective in etching copper, providing precise results.

2. Readily Available: Ferric chloride is widely available and is a popular choice for hobbyists and small-scale PCB production.


3. Affordability: The solution is cost-effective, making it an economical option for DIY projects.


In conclusion, a ferric chloride and water-based etching solution is a reliable choice for those engaged in PCB fabrication. Adhering to safety precautions and proper disposal practices ensures a smooth and successful PCB etching process.



at last create you PCB by any method I have first black painted on blank PCB then used laser machine to burn the paint from the traceses in this way I get the traces exposed and the dip it in solution and start machine.

PCB get ready in few minitus


Step 5: VIDEO