Robots - Notes - Do It Yourself Printed Circuit Boards

Use caution when working with chemicals and hand tools. No matter what I say here always follow manufacturers directions. I am not an expert on any of the items or procedures listed!

Usually you can find outstanding kits for most of the advanced items on your robot like the microcontroller or motor controller. Some times there are things that are harder to find or they may cost more than you were willing to spend. In my case I need wheel encoders and proximity detectors for every robot I make (and I am usually working on more than one robot at a time.) It is simpler to make up a batch of small circuit boards than it is to wire the same amount by hand.

Here is a brief list of items I use and some tips for making the circuit boards. There are many more (and better) web pages on DIY printed circuit boards so look around. 

Book - TAB Electronics Build Your Own Printed Circuit Board by Al Williams $18.33
Covers EagleCAD (which comes on a CD with the book) and all the procedures I used. Found the process explained on many web pages.
Software - CadSoft EAGLE Light Edition - $ Free!
Layout circuit with bottom layer only. Made sure thru holes are on a .1" x .1" grid (used 0.05" grid in program)
Paper - Pulsar Toner Transfer System 10 Sheet Pak $14.95 Digikey
Came with instructions in pack. Printed mirror image of bottom layer on TTS. Printed one test copy then used spare laser label to tape small flap of TTS over image. As the say think upside down "post-it" note.  TTS overlapped image by about .25 inch on all sides.
Blank PCB and Etchant - RadioShack PC Board Kit Cat# 276-1576 $15.49
Two 3x4-1/2" copper-clad circuit boards, etching solution, Sharpie pen to create circuit patterns
Cut blank PCB with bandsaw but a break shear would do better and a paper cutter is said to work. Please use caution.
Used cheap iron to transfer printed circuit image to cut blank.
Put prepared PCB in small Ziploc bag with etchant. I used multi-purpose disposable vinyl gloves I bought at the grocery store, $3 bag of 5 pairs. Etching took less than 10 minutes.
Removed toner with acetone from hardware store. Use as directed by manufacturer.
Drill Bits - Jameco PC Board Drill Bit P/N:16580 $1.75
PC Board Drill Bit P/N:16580 $1.75 Size: 59, Shank diameter: .125", Drill diameter: 0.040"
- The main one I used. Perfect for .1" header pins
PC Board Drill Bit P/N:16619 $1.55 Size: 75, Shank diameter: .125", Drill diameter: 0.021"
- I used this only once for very thin legs of Hamamatsu P5587 IR Photoreflector
Drill Guide - RadioShack IC-Spacing Perfboards Cat#: 276-1395 $2.59
Prepunched .042"- diameter holes in a standard 0.100x0.100" grid pattern, Size:2.75" x 6"
Used double stick tape to line up hole of perfboard with drill pads of circuit board. Used #59 drill bit on my drill press. Perfboard acted as a great guide and drilling went quickly. Perfboard can be used again.

If you have any questions or comments about this page please email me at: debots_replacethis_dinkdaze.org with at sign.