ESAB MIGMASTER 250, Instruction Manual

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3.5.2 WELDING WIRE SPOOL
As with any work area, make sure safety glasses with
side shields are worn when handling or changing
wire or clipping wire off at the spool or at the end of
the torch. Hold onto the wire coming off the spool
with one hand before clipping. Serious eye injury can
result due to the springiness of the wire which can
quickly unravel, or a cut wire end which may shoot
across the room.
Install a spool of welding wire on the hub as follows:
A. Unscrew spool nut from hub.
B. Place wire spool on hub to rotate clockwise as wire
is unwound; hub pin must engage hole in spool.
C. Replace nut.
3.5.3 THREADING WELDING WIRE
A. Turn off power switch.
When the power switch is on, and gun trigger is
depressed, the electrode wire becomes electrically
hot, and the wire feed rolls are activated.
B. Release pressure drive roll assembly and lift up
ward. Check that proper wire diameter groove is in
the inner position.
CAUTION: Before threading welding wire through cas-
ing, make sure chisel point and burrs have
been removed from wire end to prevent wire
from jamming in gun casing or liner.
C. Feed the wire from the spool through the inlet
guide, across the drive roll groove and into gun
outlet guide.
Make sure that the proper “outlet guide tube” is inserted
into the front-panel gun fitting for the size and type of wire
being used, see Table 2.4.5.2 for wire feed accessories
(Section 2.4.5).
To insure proper wire feeding, it is important that the wire
be kept clean and that the drive rolls be periodically
cleaned of any chips or scale that might be carried into
the gun liner and cause sticking.
D. Lower pressure roll assembly and secure. Check
that the gears mesh. Feed wire through to gun tip
with gun trigger (power ON).
OUTLET
CONNECTION
CYLINDER
PRESSURE
GAUGE
f. Attach the gas hose from the rear of the Migmaster
250 to the regulator outlet connection (see Fig. 3.6).
g. Slowly open the cylinder valve a fraction of a turn.
When the regulator pressure gauge pointer stops
moving, open the cylinder valve fully.
Fig. 3.6 R-33-FM-580 Regulator (Illustrated)
CYLINDER
VALVE
3.5.4 BRAKE DRAG ADJUSTMENT
Brake disc friction should provide enough drag to keep the
wire spool or core from spinning freely after wire feed
stops. If adjustment is required, turn adjusting screw
clockwise to increase drag, counterclockwise to de-
crease it. Drag should be just low enough to limit wire
overrun.
3.6 CONNECTION OF SHIELDING GAS SUPPLY
The R-33-FM-580 Regulator-Flowmeter is designed for
use with an argon or argon-mix cylinder of shielding gas.
It is adjustable for delivering up to 50 cfh through the
torch. To set up the system do the following:
Do Not adapt R-33-FM-580 for use with CO
2
. Relief
device may rupture if CO
2
is used with the R-33-FM-
580. For CO
2
service, order R-33-FM-320, P/N 21558.
a. With the cylinder cap in place CAREFULLY slide
the cylinder of gas onto the Migmaster 250 cylinder
rack.
b. Secure the cylinder to the unit, using the chain
provided.
c. Unscrew the cylinder cap.
d. Open the cylinder valve slightly, just for an instant,
to blow away any dirt or dust which may have ac-
cumulated in the cylinder valve outlet.
Be sure to
keep your face away from the valve outlet
to protect your eyes.
e. Attach the regulator to the cylinder valve, tighten
the union nut securely with a 1-1/8in. open end or
an adjustable wrench.
SECTION 3 INSTALLATION