Tweco FP-235DC - Manual (Page 12)

2. Wheels and Pull Handle - Slide the axle through the opening in the bottom of the welder cabinet. Insert axle
into wheels. Use a hammer to attach pal nuts on the axle by simply tapping them into position.
3. Assemble the plastic handle as shown in Figure 1.
4. Amperage Adjustment Handle - Thread handle onto shunt control shaft at the top of the machine until it con-
tacts locking nut (Be sure to install lock washer first). Thread crank handle into shunt handle. Tighten with a
flat blade screwdriver. Tighten lock nut against handle. Then, tighten the set screw.
5. Place the power source in a well ventilated area. DO NOT obstruct the air intake and output vents. A
reduced air flow can cause a reduced duty cycle and damage internal components.
6. Insure at least 6 feet of open space on each side of the welder.
ARC WELDING
ARC (SMAW - Shielded Metal-Arc Welding) welding metals are bonded by heating them with an electric arc
created between the electrode and the workpiece. There are two parts to electrodes used for SMAW welding.
1)The inner core is a metal rod or wire that should be similar in composition to the base metal. 2)The outer coat-
ing is called flux. There are various types of flux and each coating is used for a particular welding situation.
When the metal is molten, it can be contaminated by elements in the air. Because this contamination could
weaken the weld, the flux coating creates a protective barrier called slag that protects the molten metal from
contaminants.
When current (amperage) flows through the circuit to the electrode, an arc is formed between the end of the
electrode and the workpiece. The arc melts the electrode and the workpiece. The melted metal of the electrode
flows into the molten crater and forms a bond with the workpiece.
There are five basic choices you must make that affect your weld quality:
1. Electrode selection
2. Current setting
3. Weld angle
4. Arc length
5. Travel speed
ONLY experienced personnel should use the power sources.
IMPORTANT
Figure 1: Wheel and Handle Installation
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