Maintaining The Contact Tip; Maintaining The Nozzle - Craftsman 117-076 User Manual

Tools Required:
• 5/16 inch open end wrench
• Crescent Wrench (6 or 8 inch)
• 9 mm open end wrench (or 3 inch crescent)
• Phillips Screwdriver
• Straight Blade Screwdriver or ¼ inch hex driver
1. Turn OFF welder POWER SWITCH.
2. Open the welder side panel.
3. Loosen the tension arm and lift it up off the drive roller.
4. Turn the wire spool counter-clockwise (be sure to hold
onto the wire itself while turning the spool or the wire will
unspool itself when it becomes free of the gun liner),
removing wire from gun assembly.
5. Remove two ¼ inch hex head screws (may also be
removed with a straight blade screwdriver) and one pan
head Phillips screw (inlet guide tube end) from the drive
roller and lift away the strain relief clamp that holds the tail
end of the gun in the drive assembly.
6. Leave the gun assembly (consists of nozzle, gas diffuser,
goose-neck, handle and cable containing gas tubing
electrical cable and liner) attached to the welder but move
the welder to a place where the gun assembly can be laid
out straight on a table or workbench or similar flat surface.
7. Unscrew and remove the nozzle.
8. With a crescent wrench (six or eight inch), turn the gas
diffuser clockwise (has left hand threads) and remove the
gas diffuser (and contact tip together) from the conductor
tube on the end of the gun.
9. Remove the four Phillips head screws that hold the handle
case together. With the exception of the trigger, completely
remove the contents of the handle case.
10. Cut the plastic cable tie away from the cable covering
(tubing).
Note: In the following procedure step, it may be
necessary to remove the gas fitting from the gas
valve in order to make room to turn out the head
end of the gun liner.
11.With a 5/16 inch open end wrench, unscrew the head end
of the liner from the gas valve. Save the internal star lock-
washer and note the orientation of the live wire terminal. If
you find it necessary to remove the gas hose connector,
press down on the ring at the rear of the gas fitting to
release the gas hose and pull out the gas hose. Remove
the gas fitting with a 9 mm open end wrench or three inch
crescent.
12.Pull the liner out of the cable covering (tubing) from the
handle end and push the small piece of liner out of the
conductor tube.
13.Carefully insert the new liner into the cable taking
particular care to keep the liner straight (especially at the
terminal end) to ease its passage through cable covering.
It may be desirable, perhaps even necessary, to apply
some silicon grease to the outside of the new liner so that
it will slide easily through the cable.
14.Insert the new piece of liner in the conductor tube.
Note: If you found it necessary to remove the gas and
hose connector at step 9, remember to reconnect it
after completing step 12. The gas hose can be
reconnected by simply pushing it into the back of
the connector.
15. Insert the head of the gun liner through the internal star
lock washer and the live wire terminal (repeat the
orientation noted in step 9). With a 5/16 inch open end
wrench, screw the head end of the new liner into the gas
valve.
16. Insert a new plastic cable tie in place around the cable
and tighten it in approximately the same location as the
plastic cable tie that was cut in step 8.
17. Return all components to the handle casing and realign
them as they were originally.
18. With both halves of the handle case in place, tighten the
four Philips pan head screws making sure the trigger
remains seated in place.
19. Push the cable into the welder far enough so that the end
of the gun liner protrudes through the inlet guide tube end
of the wire-feed torch clamp far enough so that it is within
approximately 1/16 inch of touching the drive roller.
20. Make sure the cable covering (tubing) is far enough in the
machine so that it is covered by the wire-feed torch clamp.
21. Tighten the two ¼ inch hex head screws (may also be
tightened by a straight blade screwdriver) and one pan
head Phillips screw to the drive roller securing the gun in
place.
22. Re-install the welding wire according to INSTALL THE
WELDING WIRE.

MAINTAINING THE CONTACT TIP

The purpose of the CONTACT TlP is to transfer welding current
to the welding wire while allowing the wire to pass through it
smoothly.
Always use a contact tip stamped with the same diameter as
the wire it will be used with.
1. If the wire burns back into the tip, remove the tip from the
gun and clean the hole running through it with an oxygen-
acetylene torch tip cleaner or tip drill.
2. Over time, the hole in the contact tip will become worn by
the wire passing through it. The more worn this hole
becomes, the less efficient is the transfer of welding current
to the wire and eventually arc breakage and difficult arc
starting will result. Replace contact tips when signs of wear
become apparent.

MAINTAINING THE NOZZLE

The nozzle directs the shielding gas to the weld puddle,
determines the size of the shielding area, and prevents the
electrically hot contact tip from contacting the work piece.
KEEP THE NOZZLE CLEAN! During the welding process,
spatter and slag will build up inside the nozzle and must be
cleaned out periodically. Failure to clean and/or replace
the nozzle in a timely fashion WILL CAUSE DAMAGE TO
THE FRONT-END OF THE GUN ASSEMBLY.
For best results, coat the inside of a new or freshly cleaned
nozzle with anti-stick spray or gel.
1. Stop welding and clean any accumulated slag or spatter
from the nozzle every 5 to 10 minutes of welding time.
2. When welding overhead, if any molten metal drips from the
weld puddle and falls into the nozzle, STOP WELDING
IMMEDIATELY and clean the nozzle.
3. If the slag cannot be thoroughly cleaned from the nozzle,
REPLACE THE NOZZLE!
CAUTION
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