Explain how to thread FCAW wire.

Question

What will be an ideal response?

Answer 1

Cut off the end of the electrode wire if it is bent. When working with the wire, be sure to hold it tightly. The wire will become tangled if it is released. The wire has a natural curl known as cast. Straighten out about 12 in. (300 mm) of the curl to make threading easier.


Separate the wire feed rollers and push the wire first through the guides, then between the rollers, and finally into the conduit liner. Reset the rollers so there is a slight amount of compression on the wire. Set the wire-feed speed control to a slow speed. Hold the welding gun so that the electrode conduit and cable are as straight as possible.


Press the gun switch. Pressing the gun switch to start the wire feeder is called triggering the gun. The wire should start feeding into the liner. Watch to make certain that the wire feeds smoothly and release the gun switch as soon as the end comes through the gun.


If the wire stops feeding before it reaches the end of the gun, stop and check the system. If no obvious problem can be found, mark the wire with tape and remove it from the gun. It then can be held next to the system to determine the location of the problem.


With the wire feed running, adjust the feed roller compression so that the wire reel can be stopped easily by a slight pressure. Too light a roller pressure will cause the wire to feed erratically. Too high a pressure can crush some wires, causing some flux to be dropped inside the wire liner. If this happens, you will have a continual problem with the wire not feeding smoothly or jamming.


With the feed running, adjust the spool drag so that the reel stops when the feed stops. The reel should not coast to a stop, because the wire can be snagged easily. Also, when the feed restarts, a jolt occurs when the slack in the wire is taken up. This jolt can be enough to momentarily stop the wire, possibly causing a discontinuity in the weld.