In this tutorial we are going to build our own servo extension. In this tutorial we will go through step by step on how achieve a 150mm (6inch) 22awg Futaba servo extension lead. Each image can be enlarged by clicking on them First of all we are going to need some tools. From left to right they are as follows: Ruler. Small flat head screwdriver (1.4mm). Pair of side cutters. Set of automatic wire strippers. High quality crimping tool (orange handles). We found better results from reversing the dies. If you leave the tool as is, the pin will twist slightly when its being crimped. The picture on the left shows the dies already changed over. Remove the 2 screws that hold the dies in place and re-position them as shown. The small V-shaped slots should be in the right hand side with the smallest V at top (The crimp tools writing facing up). Once in position do not tighten the screws just yet. Close the crimp tool like the picture on the right, then tighten the screws. This will make sure its in the correct position.   On the tool there is a slotted disc to allow you to adjust the tension. Tension being when the tool will release itself from the ratchet mechanism. If you use thin cable ideally you want the tool to apply more pressure during the process than say a thicker cable. If you apply to much pressure then you can deform the pin quite badly which would weaken the pin. Not enough pressure the cable can be pulled away from the pin. This process is trial and error. On Heavy duty servo cable the second slot from the + sign seems to work best. More to the positive side releases the jaws early. Let’s identify the connectors. At the top left of the picture is the male housing. At the top right is the female housing. This slides on to the male housing to convert it into a female. On the bottom left is a male crimp and on the bottom right a female crimp. note: Male = Plug. Female = Socket. Now let’s start making our extension. First of all cut your cable to length. For best results cut the cable all in one go rather than each wire in turn and cut it as square as you can at both ends. Also try to use a set of side cutters that have a long enough cutting edge. Now we have our cable cut to the correct length. Now it's time to strip it ready for crimping. First of all we to split the cable. Using the side cutters line up the blade in between the two a joining wires. Be careful here, if you don't have the blade lined up correctly you could cut in to the insulation.   You only need to split them about 10mm or so. I've opened out the wire here to show you but try to keep the wires as straight as possible as it would make your life easier when it comes to stripping. Place the cable in the jaws as seen. We need to strip about 3 - 3.5mm. The Good thing about this tool is that we can strip all three wire simultaneously. Make sure you lined up all three wires parallel to the cutting blade in order to achieve equal stripping. This can be correctly later if it does not quite work out. If your lucky to have a set of strippers with a length adjustment then its about 2 clicks from the most forward position. With all three wires stripped. Gently separate the wires from each other until you have an individual length of 20-30mm. As you gain experience this distance can be reduced. Now look at the stripped ends and if they are not equal (insulation removed) they can now be re-stripped. Here is a crimp (male). It has two sets of wings! A1-A2 is the strain relief. This wraps round the wire insulation. B1-B2 wraps round the wire strands and gives the electrical connection. Now we are ready to do our first crimp. Always start with the negative wire towards you as shown. (Black = Futaba, Hitec, Sanwa, Airtronics, Traxxas. Brown = JR). Hold the wire & crimp as seen on the picture on the left so the bare strands are between B1 & B2 & the insulation between A1 & A2. Once you have a firm grip pinch the wings of A1 & A2 to bring them together as seen on the right picture (best results use your nails). This finger crimp will make your life easier later.   Here are the actual crimp die (lower half). From the pictures, you can see, like the crimp it has two halves. The die will crimp both parts in one pass. Normal crimping convention is to line up A1 with the Right edge of the die. Since these crimps are slightly smaller than normal non-insulated crimps this rule does not apply. Good example why, can be seen from the picture of the right. The crimp shown is a BEC crimp. If you were to crimp like this then it would close the end part of the connector which would not allow the pin of the mating crimp to be fully inserted. For this reason it is good practice to line up the crimp by B2 flush or 0.25mm in on the left side of the die.   Now we can do our first crimp as seen on the left picture. Gently load the crimp assembly in position making sure it's square before closing the jaws. Then crimp until you hear the tool click once! this will allow to make further adjustments if need be. Once your happy, follow through until the ratchet mechanism is released. Then your first crimp should look like the right picture.   Once your happy, follow through until the ratchet mechanism is released. Then your first crimp should look like the left picture. Repeat this for the rest of the wires until all three are done. Now insert the crimps into the plug housing by hand until you can't push them in by hand any further. Hold the connector like you would a key (below picture). Then using the tip of the flat screwdriver to gently push the crimp in until A1 is flush with the housing . As the crimp slides down you will see and feel the fingers of the housing raise. Once again with the tip of the screwdriver gently rest the tip on the bottom of A1 and apply a small force to push the crimp. You will know when you have done this. Firstly you will hear a click but more importantly holding the connector in this fashion you will feel the finger drop down. Do this for all three wires. And that's it one side done! All we have to do now is to repeat it again but using the female crimps. When it comes to do the female side you must start on a certain colour otherwise you will have your connectors the wrong way round. The dots correspond to the colour that should be used.   Type Male (Plug) Female (Socket) Futaba     JR     HiTec     Sanwa/Airtronic       The female end uses female crimps and a male housing. So you end up with something like this. If you look inside the female housing you will see three ridges sticking out as indicated in red on the left picture. This is used to clip securely the housing on to the connector and convert this into a female connector. Slide it on until it clicks in place. For what ever reason you get into trouble crimping. The tool has a release mechanism. Slide the lever in the direction shown and the jaws will be released. And that's it! All done! Now you can make your own extensions at any length. If you have any questions or queries then please feel free to email me at ash@ashtekelectronics.com Happy Crimping!