Craftsman 196.205680 Manual Del Usuario página 19

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If the wire burns back into the tip, remove
the tip from the gun and clean the hole
running through it with an oxygen-acety-
lene torch tip cleaner or tip drill.
.
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.
CAUTION
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, which is
NOT REPLACEABLE. The results of the
inaction will REQUIRE THE REPLACEMENT
OF THE ENTIRE GUN ASSEMBLY.
1. Stop welding and clean any accumulated
slag or spatter from the nozzle every 5 to
10 minutes of welding time.
2. If slag cannot be thoroughly cleaned from
the nozzle, REPLACE THE
NOZZLE!
Failure to keep the nozzle adequately
cleaned can result in the following problems:
A SHORTED nozzle results when spatter
buildup bridges the insulation in the nozzle
allowing welding current to flow through it as
well as the contact tip. When shorted, a
nozzle will steal welding current from the
wire whenever it contacts the grounded work
piece. This causes erratic welds and reduced
penetration. In addition, a shorted nozzle
overheats the end of the gun which can
DAMAGE the front-end of the gun.
TESTING FOR A SHORTED NOZZLE
Arcing between the nozzle and the work
piece ALWAYS means the nozzle is shorted,
but this can be hard to detect through the
lens of a welding helmet. The following
testing method is another way to tell if a
nozzle is shorted.
With the welder unplugged from the ac
power source, touch the probes of an ohm-
meter or continuity tester to the end of the
contact top and the outside of the nozzle. If
there is any continuity at all, the nozzle IS
shorted. Clean or replace as needed.
REPLACE A GUN LINER
When installing a new gun liner, care must
be taken not to kink or otherwise damage the
gun liner. See Figure 18 for the drive assem-
bly and Figure 19 for the gun assembly.
1. Turn OFF welder POWER SWITCH and
unplug welder from power supply.
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 turn-
ing the spool or the wire will unspool itself
when it becomes free of the gun liner), and
remove wire from gun assembly.
5. Lay gun cable and gun handle straight
out in front of unit.
6. Remove gun liner holding clamp by
removing two self tapping screws and
two bolts with nuts.
7. Take gun handle halves apart by
removing five phillips head screws.
8. Remove liner from fast coupler fitting on
brass block. Depress lip on fast coupler
back towards fitting and pull liner out.
9. Remove liner from outer torch sleeve and
pull out.
10. Remove fast coupler fitting from brass
block.
11. Install new liner, starting from handle end
and feeding towards unit with fitting end
of liner going towards the brass block.
12. Fit liner for length at feeder end by cut-
ting liner with wire cutters.
13. Reinstall liner holding clamp at feeder.
14. Return all components to the handle
casing and realign them as they were
originally.
15. With both halves of the handle case in
place, tighten the five phillips head
screws.
16. Reinstall the welding wire according to
specifications in INSTALL THE WELDING
WIRE section.
17. Close side panel.
18. Plug welder into power supply and turn
POWER SWITCH to ON position.
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