Splicing wires is a simple chore

Have you observed that the cords furnished with many appliances seem to be just a trifle too short to reach the nearest outlet? An extension cord is a help, but the real cure is to add a permanent length of wire to the existing one.

Electrical and hardware stores carry a variety of cords and wires, and you can match the old and the new without much trouble. Joining them is a simple hand operation, and requires the use of only pliers, knife and soldering iron. If you are new at the game, it is a good idea, of course, to make a few practice joints with scrap pieces of wire.

Cords of all appliances contain flexible wire, which actually consists of a bunch of very fine wires held together by the covering of insulation. Solid wire is found in power conduits, bell circuits, intercom hook-ups and other fixed applications.

The secret of good electrical joints is merely cleanliness. The quickest and easiest way to brighten up wire is to scrape it very lightly with the back edge of a knife.

The wire inside most cords is bare copper. Depending on the age of the cord and the type of insulation, the metal might, be of any shade from shiny bright to corroded black. In the better grades of cords, the wire is "tinned"; that is, covered in manufacture with a very thin layer of solder. This usually remains quite clean, and takes solder instantly.

Outer layer of insulation is best removed with sharp knife, in same manner as sharpening pencil. Make three or lour short incisions, blade held at flat angle, then twist off insulation with the fingers. Be careful with depth of cut, to avoid nipping off outer strands of wire. Twist wires and scrape  lightly  with back  of  knife  if  dirty.

With practice, you can remove insulation quickly with side-cutting pliers. Sever insulation by making a carefully controlled cut, and with jaws still partially closed, pull the covering off. The trick is to cut the insulation without nicking the wire. Some types of insulation do lend themselves well  to this  method,  while  other types  do  not.

Spliced wire will show minimum thickness at points of joining if ends of the new and old wires are stagger-cut to length of about two inches. This is  first   step  in   splicing   common   twisted   lamp   cord.

Illustrations show typical splicing jobs. ·

Twist together the long wire of one cord with the short wire of the other. Leave the other pair apart. The idea is to complete only one joint at a time. The job conies out neater in this manner.

Using rosin-core solder, make first joint solid. Then leave the iron in contact with the connection until all of the rosin has boiled out and you have only a shiny coat of solder remaining.

The next step is to finish the first joint by taping it tightly. A good sticky tape for this purpose is sold as "friction tape," is obtainable in a width of about ¾ inch and color is black.

Staggering preserves general lines of the cord. If it is not convenient to solder the joints, make them about two inches long and tie them up with three or four strands from the cut-off ends.

Light colored cords don't look attractive when spliced with black friction tape, so why not use white tape? Borrow some adhesive tape from the medicine chest. You'll find   it  sucks   tightly   and   insulates   well.

For splices that need protection against water, oils, acids, etc., an excellent tape is Scotch No. 33. It can be pressed with fingers to shape, and proves to be  virtually air and liquid tight.

"Wire nuts" are widely used in both new and revamped electrical wiring because they offer quick and easy means of joining wires without soldering. This is an advantage when no current is available for a soldering iron (power circuit having been deactivated to permit work to be done on it) and when use of a blowtorch or other open flame is too hazardous (which is often the case). The wire nut comprises an insulated body with threaded metal insert. The wires to be Joined are pushed into the latter and the nut turned in either direction two or three times; the threads bite into the wires and twist them together. Nuts are identified  according  to  the  wire  sizes  they  fit.

If the wires are bared to the proper length, a wire nut will be found to insulate your splice properly, and it is obvious that no additional covering in the form of tape is then necessary.
 
In this case, the wire ends have been bared too much and the unprotected sections remain exposed after the nut has been tightened. The joint can be easily opened and the wire then recut to fit.

Quick-heating soldering "gun" makes a fast job on wire splicing. Here, it is being used on single-conductor solid wire which is usually found in power conduits. See position of gun point and solder in relation to the joint. As the solder melts, the molten metal runs into the joint and forms a firm bond over the termini of the wires.

Solid wire in the No. 18 size, and smaller, is used for bell, buzzer, intercom and like low voltage applications. Easiest way to splice wire of this type is to twist the ends together with a pair of pliers. Soldering is advisable but not as important as in power circuits. Taping is necessary,  of  course,  for prevention  of short circuits.

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