Tools and Equipment required:
You’ll need some kind of circuit designing CAD program to make a schematic and layout for your board, I use EagleCAD by CadSoft
- Copper Clad Board – 1 oz copper or less recommended http://www.digikey.com
Don’t buy “pre-sensitized” boards; they are for transferring the image photographically.
- Toner Transfer Paper http://www.pcbfx.com/main_site/pages/products/transfer_paper.html
- PCB Etchant Solution (Ferric Chloride) - Radioshack usually has this in stock
- Nail Polish Remover
- Nylon Abrasive Pad - The thin green Scotch-Brite scouring pads cut into 1.5 inch squares
- Laser Printer
- Clothes Iron or laminator ("APACHE" model AL13P found on Amazon)
- Hot Water
- Latex/Rubber Gloves
- precision finger drill or mini drill press (Model GTT-104)
- Soldering equipment (soldering iron, solder, moist sponge, flux and the knowledge to use it all)
You first need to design and layout your board. Create the schematic and then the layout taking care that each component you plan to use is placed correctly and will fit with the other components in your drawings.
Be sure parts fit your design. I will print the schematic on my regular printer and "fit" the components to the paper and make any adjustment to the design if needed before I print to photo paper (do this with non-static sensitive parts ONLY!).
Print the Design
Print the design from a laser printer (NOT ink jet) using the darkest settings and highest resolution (e.g. Quality=Best, Intensity=Darkest, etc…). The goal is to get the greatest amount of toner onto the photo paper. Also, be sure to select “Photo Paper” or “Glossy Paper” as the paper type.
Now cut out the design around the boarder leaving about 1/8” of extra paper on three sides and 1” of extra paper on the fourth side (to grab it by).
Never touch the board part of the photo paper before or after it has been printed.
Transfer Design to Copper Board
Protect your skin: Use rubber gloves to when working with the acetone!
- Remove Toner Treansfer Paper
If things go wrong: If the toner transferred well except for a couple spots you can fill in the gaps with a resist ink pen (Sharpie). If there are more than just a few bad spots, you have the option of redoing the whole process. Just use hot water and a Scotch-Brite pad to rub off the toner and start over!
- Etch the Board
• Heat the solution in the oven or microwave to 110°F
• Jiggle the dish to provide some gentle agitation
• Gently wipe the surface of the board with a balled up paper towel as it etches
Keep if off the clothes: Be careful when working with the etchant solution. It will stain almost everything it touches! Flush it down the toilet if you have a steel sink.
Be careful not to over etch the board or your traces will begin to eat away from the side. If the whole board is etched (translucent looking) except for some stubborn spots, pull the board out of the solution and attack those spots individually. A Q-tip works well for this.
- Remove Toner
- Drill Holes
- Solder Components
- Fabricate the enclosure and make connections
The full monty –
Click here for other pics of putting it all together
Enjoy your new project!
Scotch-Brite is a registered trademark of 3M corporation.
Q-TIPS is a registered trademark of Unilever.