Tweco FP-235DC - Manual (Page 15)

5. Select the appropriate electrode.
6. Turn on the power switch of your welder.
Arc rays can injure eyes and burn skin! Prolonged exposure to arc rays
can cause blindness and burns. NEVER strike an arc or begin welding without ade-
quate eye and skin protection. Follow our Health Hazard safety instructions on
page 4 before welding.
WELDING POSITIONS
Arc welding can be performed from any of four basic positions
1. Flat - generally easier, faster, and allows for better penetration of the metal
2. Horizontal - generally easier, faster, and allows for better penetration of the metal
3. Vertical - usually used only when welding with DC welding capabilities
4. Overhead - considered the most difficult, usually used only when welding with DC welding capabilities
For best results, position the workpiece so that the bead will run on a flat surface.
PREPARING THE JOINT
For the most effective welding, surfaces to be joined must be free of dirt,
rust, scale, oil or paint. Welding on metals not properly cleaned will result
in brittle or porous welds.
If the base metal to be joined is thick or heavy, it may be necessary to bevel
the edges with a metal grinder directly at the point of contact. The angle of
the bevel should be approximately 60 degrees.
When grinding, ALWAYS wear goggles.
The grinder MUST also be inspected to verify it is in good condition.
For the types of Weld Joints, see Figure 2.
During the process of welding, workpieces will become very hot and tend to expand. This expansion may
cause the pieces to shift from the beginning position. If possible, workpieces should be clamped into position
required when the welding is completed.
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Figure 3: Workpiece Preparation
Figure 2:Welding Positions