Lincoln Electric IDEALARC SP-250 Service Manual page 28

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4. Press the CENTER UP & DOWN ARROW keys to
set the required Spot On time. Suggested initial
setting is 1.2 seconds.
5. Press the SPOT key.
screen. Spot timer status is shown in bottom left
corner of screen.
6. Install spot weld nozzle (if available) on gun.
7. Press spot weld nozzle against the top sheet so
the top and bottom sheets are tight together. If a
spot weld nozzle is not used, smoother welds will
result by moving the welding wire in a small circle
while making the weld.
8. Close the trigger and hold it closed until the arc
goes out.
MAKING A STITCH WELD IN AUTO MODE
A stitch weld is used to weld thin material because
warpage and burnthrough are a problem. Properly
adjusting the ON and OFF times and arc travel speed,
permits welding thin sheet metal using small welds that
result in minimum distortion and no burnthrough.
To make a stitch weld
1. Set the procedure for the metal thickness to be
welded.
2. Press STITCH key. Stitch screen is displayed.
3. Press CENTER ARROW keys to set Stitch ON
time. Start with a Stitch ON time setting of 0.5 sec-
onds. Increase the Time ON setting to increase
penetration and weld size. Decrease the Time ON
setting to reduce burnthrough and distortion.
4. Press the RIGHT ARROW keys to set the Stitch
OFF time. Start with a Time OFF setting of 0.5
seconds. Increase the Time OFF setting to reduce
burnthrough. Decrease the Time OFF setting to
produce a flatter and smoother weld.
5. Press STITCH key.
Stitch timer status is display in lower left portion of
screen.
6. Close the gun trigger and hold it closed for the
length of seam. Hold gun in one place during ON
time and move gun just beyond edge of molten
metal during OFF time. For smoothest welds on
thinner metal, point gun slightly towards the direc-
tion of travel.
OPERATION
Display returns to Auto
Auto screen is displayed.
IDEALARC SP-250
USING THE GUN TRIGGER SWITCH
The Gun Trigger Switch turns on arc voltage, wire
feeder, and gas solenoid (except with Innershield)
when the Gun Trigger Switch is closed. When closed,
the LED screen displays the Auto or Manual screens,
depending on which mode is being used. When the
Gun Trigger Switch is released, or opened, arc voltage,
wire feeder, and gas solenoid are turned off.
NOTE: When the trigger is pulled, the wire feeder
feeds wire at low speed regardless of the set wire feed
speed until the welding arc starts or 2 seconds has
elapsed. This feature enhances starting and makes it
easier to set the stick out. The 2 second limit permits
high speed loading of the gun and cable.
USING THE GUN
(MAGNUM SP-250 ONLY)
The Gun Thumb switch is used to control wire feed
speed, arc voltage, or to switch, or toggle, between
memory locations 4 and 5. See IPM VOLTS key and
TOGGLE key for control details. The Thumb switch is
used to increase or decrease IPM or VOLTS.
USING THE WIRE DRIVE ROLL
The drive roll provided with the SP-250 has two
grooves, one for .030"-.035" (0.8-0.9mm) solid steel
electrode, and the other for .045" (1.2mm) solid steel
electrode. The welder is shipped with the drive roll
installed in the .030"-.035" (0.8-0.9mm) position as
indicated by the stenciling on the exposed side of the
drive roll. If .045" (1.2mm) electrode is to be used or
one of the optional drive rolls is required, then the drive
roll must be reversed or changed per the instructions
provided on the instruction decal inside the SP-250
Drive Roll Access door.
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THUMB SWITCH