Your fish tape broke. You don't have time for the round trip to get another one and still finish the job today. Will you have to come back tomorrow? Not if you know how to fix it in the field.
Some people skimp on a quality fish tape because "those tapes break, then I'm out the extra money." Well, the newer fish tapes are much more break-resistant than their ancestors; however, fish tapes still break. The good news is you can repair a fish tape. While the procedure for repair depends on the type of tape, no matter what type of tape you are repairing, make sure to wear your safety glasses whenever you use or repair a fish tape. Always inspect the fish tape for damage or kinks. Then, remove any damaged or kinked tape prior to repairing. Let's look first at the swivel ball on spring steel fish tape.
Repairing a tape with a 1/8-in. swivel ball end. To remove the swivel ball from an old tape, unscrew the pulling eye from the base and slide the base away from the crimped end of the tape. Cut off the crimp and slide the base off of the fish tape. (If you are using a new swivel ball, this step is unnecessary.) If you are using a new fish tape coil, cut off the preformed loop.
Next, slide the base onto the fish tape. Use pliers to hold the tape, or place the tape on an incombustible table and heat its end to a dull red color with a torch. Do not hold the tape with your hands while heating; the tape gets very hot even 2 ft away from its end! While the tape is red, use a pair of pliers to make a curl at the end. Make the curl approximately 3/16 in. long.
Reheat the tape's curled end to a dull red state again and allow to air cool. Do not quench in oil or water. This reheating process will anneal the metal and reduce fatigue and brittleness. This decreases the likelihood of another break.
After the tape has cooled enough for you to handle it again, slide the base to the end of the tape and reassemble with the pulling eye. Tighten the assembly with a wrench or pliers to secure the parts together. The swivel ball should turn freely on the end. If it doesn't, you'll have to disassemble the ball. Then reheat, reform, and anneal the end of the fish tape again.
This same procedure applies to repairing a tape with a quarter-inch swivel ball end, with one exception. For the larger tape (quarter-inch swivel ball end), grind approximately 2 in. of fish tape to 1/8 in. wide. Then follow the same procedure that applies to the smaller tape (1/8 in. swivel ball end).
Repairing the loop on a spring steel fish tape. The repair method is the same for all sizes of this type of tape. First, cut off the damaged part. Again, holding the tape with a pair of pliers or placing it on an incombustible table to protect your hands, heat the tape where you need to make a bend until it is a dull red color. With another pair of pliers, bend tape to form a completely enclosed loop. To do this, make a 90 degree bend about half inch from where the loop should begin, then bend the tape over to complete the loop.
Reheat the loop end of tape to a dull red, and allow it to air cool, annealing the loop. Quenching weakens the bend, possibly causing it to break while in use, causing serious injury.