Introduction: DIY Servo Extensions
Are you working on an Arduino or robotics project using servo motors where the wires aren't long enough? Then you need servo extensions. You can buy servo extensions at many hobby stores and online. They are designed for a particular brand of servo and have specific end connectors that usually don't fit my needs.
When working with DIY robotics projects we usually need some kind of custom servo extension so I'm often making up a special connector. I am also preparing for a Soldering Workshop at the CCCKC Hacker Space so this Instructable will help serve that purpose too.
Another gratuitous plug for CCCKC.
Building servo extensions are not breakthrough technology for an Instructable but this might help someone pick up a few tips.
Instructable By: SomeoneKnows
Step 1: Gathering Parts and Supplies
Solder and soldering iron.
Clippers, saw and small vice.
Heat gun or lighter
Male and Female connection headers
Use a low wattage soldering iron. 15W to 30W works best for me.
Solder - Some solder may contain lead so don't put it in your mouth (I saw someone do that once).
It is possible to use individual stranded wires but I like to use the 24 awg three conductor servo wire I bought from Servo City. It comes with the correct layout of the wires, red for + power connection, black for ground, and white (or yellow) for the signal wire.
Step 2: Preparing Header Connectors.
I wish Radio Shack stocked these male and female connection headers so I can just run down to the store when needing more. I usually order mine from DigiKey:
Female connetion headers DigiKey S7049-ND
Male connection header DigiKey S1012E-36-ND
The connection headers come with more pins than needed so they need to be cut down to only three. With the male pins this is easy with the clippers, place the blade in the little indentation and snip off your pieces. Be careful to hold both sides otherwise the pieces will fly off and get lost or hit someone in the eye.
The female connectors take a little more work. I like to use the band saw and cut off the amount needed. This requires special care that you don't get your fingers in the blade. I use a piece of solid core wire and stick into the smaller part that will be cut off so it doesn't fly away or fall into the machine after its cut.
The plastic part is not hard to cut and can be easily done with a hand saw too. If you are doing this by yourself you might want to get a small vice to hold the part in place.
Step 3: Preparing the Wires
Cut wire to the length needed.
Separate the wires. I've used a knife to slit the wire for separation but I like using these clippers instead.
Peel away enough wire for room to work.
Use wire strippers to remove insulation. Try to limit the length you take off to coincide with the length of the pins you're attaching to.
Twist the exposed strands of wire to keep them from fraying out an causing a possible short circuit.
Tin the wires to keep the strands in place and it makes attaching to the pins easier.
Step 4: Finishing Your Work
Before sealing up your work check for short circuits caused by solder bridging between any pins.
I like to use shrink tubing to tidy up the work, I'm using an assortment pack from Radio Shack. Simply select the diameter that fits best then cut off a piece, insert over wires, and apply heat to shrink the tubing. I like using a heat gun but sometimes use a lighter. Be careful not to over heat or burn your wiring. Too much heat can melt the plastic holding the pins in place too.