Custom Circuit Boards
In this Instructable will show how I make custom circuit boards and Arduino shields for my projects. The instructions will be general showing the basic methods I use and examples of boards I have made. These instructions are written for people who can prototype electronic projects and have basic soldering skills. These instructions do not provide detail steps for mounting all components. I hope this will give you ideas on how you can use these methods for building custom circuit boards your projects.
Step 1: Methods:
In general, I make all the more expensive components removable and the inexpensive components like LEDs, resistors and switches soldered to the board. I also use plain old perf board with no metal solder pads. Perf board can be easily cut to fit your project. Lately I have been making my own boards on a 3-D printer. The methods used are the same.
Wire Wrap: I have seen wire wrap refereed to as “Lost Knowledge”. I don't find reference to this method being commonly used, but I find wire wrap an extremely handy way to make wire connections that are solder-less and very reliable. This method requires a wire wrap tool and wire wrap wire. You will need pins that protrude from your perf board long enough for the tool to work. Here are instructions on how to wire wrap on Instructables.
Soldered Connection: If the pins are too short for a wire wrap tool, I use a soldered connection. To make a component removable, I solder on a header or IC socket. The component can be plugged into the header or socket. The header is superglued to the perf board. Use small gauge wire like 30 gauge wire wrap wire. Strip about ¼ inch of the insulation from the end of the wire. Wrap the wire around the pin using a small flat head screw driver. Solder the wire to the pin. You can do just a half wrap, but the wire need to be tight enough to stay in place to make the solder connection. Remove any extra wire with a side cutter. The female header can be cut to size with a hack saw or coping saw. I cut right through the next unused hole, cut down through the metal connector. Touch it up by filing the rough cut end of the header.
Step 2: Board Layout:
Here are general steps to do before wiring up your circuit board.
Prototyping: First prototype your circuit on a solder-less breadboard. When your circuit is ready
to be moved to a circuit board, you will need to plan the layout and wiring.
Board Layout: You can draw your wiring diagram and wire routing using graph paper or use a program like Fritzing. In Fritzing, I like to manually route the wires to plan out the best routing. The 30 gauge wire is small enough to run it through the perf board holes to make orderly wire routing. When you have a completed layout that you like, cut the board to the right size using a hack saw or coping saw.
Component Placement: Using your diagram, pencil the locations of headers and components onto the perf board. Glue the headers onto the perf board. Wire wrap or solder wiring per your diagram.
Board Layout Considerations: Headers will add thickness to your completed project. Wire wrapping directly to the perf board will reduce the thickness. Consider the placement of displays, buttons, switches or other controls and build your layout around these. If you need access to USB ports or SD cards they will need to be positioned at the edge of the board.
Step 3: Arduino Shields:
You can use the same methods to create an Arduino Shield. You will need to use male header pins for the female headers to connect to. Digital 9-13 pins are offset and will not line up with the holes in the perf board. I use a dremmel and a cutting blade to cut a slot between these holes. The slot is finished off with a hack saw blade. Using the Arduino for a guide, line up the offset pins and super glue the female headers in the proper location on the perf board.
Don't limit yourself to a circuit board the size of your Arduino. You can make the circuit board bigger and put the male pins on the bottom side of your circuit board to attach your Arduino.
Step 4: 3D Printing:
If you have a 3D printer, you can not only make your own custom cases for your circuit boards, you can make your own circuit board. Better yet, you can integrate the circuit board into the case. The methods for wiring are the same.
You can download my 3D printer files on Thingiverse. My user name is DaveGun. Not all the 3D projects shown here are available on Thingiverse at the time of this writing, but I plan to add them in the future.
Step 5: Conclusion:
In the instructions we covered the basic methods for wire wrapping or soldering headers. We discussed circuit board layout, Arduino Shields and finished with an example of 3D printed boards and integrated 3D printed boards. I hope this gave you some useful information or ideas and will inspire you to create your own custom circuit boards.