Bill of Materials
- Ferrous Chloride (PCB Etching solution)
- PCB Board
- Express PCB on PC. http://www.expresspcb.com/.
- Laser Printer or ( INKJET Printer and Photocopier which uses LASER printers ink)
- Ordinary Paper
- Permanent Marker PEN
- Hot Iron box
- Kitchen Dish wash bar (VIM dish cleaning bar)
- Scrub Pad
- Tissue Paper
- Paint Thinner Solution
- 0.1''(inch) drill bit and 0.08"(inch) drill bit
- Hand Held Driller/ Motorized Driller.
Caution : You are gonna play with Industry Grade Corrosive Solutions. Wear Eye Glasses and protecting gloves before working on this.
1. DESIGN OF PCB CIRCUIT
PCB components
Pad - The portion of the conductive pattern on printed circuits designated for the mounting or attachment of components. Also called land.
Traces - Literal wire for connecting pads and nodes.
A width of 0.010" is a good default for digital and analog signals. For power lines, use traces 0.05" or wider.
LAYERS of PCB board
Red -- Top copper layer selection
Green -- Bottom copper layer selection
Yellow - Top silk layer
Start designing the circuit and finalize the design.
2. PRINT OUT the circuit (Toner Transfer Method)
Issue a print out on the Laser Printer. Make sure to make darkened printout. This can be done by changing the printer darken properties. If you happen to have Inkjet printer make sure to print the circuit and obtain a photocopy on photocopier with LASER printer INK. Make sure to darken the copy Image too.
Note: You may/may not need to mirror the circuit image before printing out the circuit on the paper. This step may be need as per your design of the circuit.
Note: Laser Printer Uses TONER INK. Any printing device using TONER INK is sufficient.
My Printout of the circuit. If you have multi layered PCB(usually 2 layered). Make sure to take one printout for each layer. I went with single layered PCB only.
3. PCB Cleaning
Wash the PCB Kitchen Dish wash bar (VIM dish cleaning bar or any alternate). Make sure to use the scrubber pad and remove all the oily residue attached on the top of the PCB. Wash with water. Wipe it with dry Tissue. Don't ever touch the Copper side. Your touch places oil back on the PCB.
4. IRON Out the Circuit to the PCB
Make sure to place the circuit print on the copper side and fold out the rest of the paper around the PCB. Use of Sticking tape is not encouraged, as Tape tends to melt out when heat is applied. Apply the Hot IRON on the Paper. Make sure to apply heat uniformly across all the sections of the circuit. Keep the heat and press on the paper for minimum of 10 minutes.
Caution : You are playing with HOT IRON. You may get burns if not used properly. Entire PCB board with the Paper on top will be so hot to hold.
5. CIRCUIT on PCB
After hot iron, give some time to cool out. You will now notice that the CIRCUIT INK melted and stuck to the PCB board. Immerse, the PCB into water and start peeling of the paper. You get the Circuit on the PCB.
6. CORRECTION on PCB circuitry (if any)
You can use the Permanent Board marker to sketch up the left over circuit traces.
7. FERROUS CHLORIDE (the Magic Solution)
Make sure to read the instructions on the solution pack. Usually this chemical comes as a power form. You need to make sure to follow the instructions given in the pack to make the liquid form(Mix with water). Ferrous chloride eats away any exposed metals which comes in contact. Even its vapor is corrosive. Tie the PCB to a Plastic wire and lower it into Ferrous Chloride, which is contained inside a Plastic box. Ferrous Cloride can't attack Plastic. Never touch the solution on bare hands. If happened to touch it accidentally, wash it thoroughly on soap and running water.
Caution : You are gonna play with Industry Grade Corrosive Solutions. Wear Eye Glasses and protecting gloves before working on this.
Make sure to shake the container often, so that the solution is spread out evenly. Generally, it takes less than 20 minutes to etch the metal fully. You have to take out the PCB with the tied wire to check this.
8. PCB Cleaning
Once all the exposed metal are etched away. Dip the PCB in water. Use Kitchen disk wash bar and Scrubber pad to clean the TONER INK. You can also try Thinner solution on the PCB to remove TONNER INK.
10 . FINAL PRODUCT
Note : You have to use the Driller to punch hole for the components mount pads.
