Spot Welding; Punch And Fill Method; Lap Spot Method - MasterCraft 058-8194-4 Instruction Manual

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Spot welding:

There are three methods of spot welding:
1. Burn-through method: In this method,
two overlapped metal pieces are welded
together by burning through the top
piece and into the bottom piece. The
wire suitable for this method is 0.035
inch self-shielding, flux core wire.
Always select the high heat setting for
this method and tune in the wire speed
prior to making a spot weld
Note: Do not use 0.030 inch self-shielding flux
core wires when using this method unless the
metal is very thin or excessive filler metal and
minimal penetration is acceptable.
2. Punch and fill method: This method
produces a weld with the most finished
appearance. In this method, a hole is
punched or drilled into the top piece of
metal and the arc is directed through the
hole to penetrate into the bottom piece.
The puddle is allowed to fill up the hole
leaving a spot weld that is smooth and
flush with the surface of the top piece
(fig U)
3. Lap spot method: The welding arc is
directed to penetrate the bottom and top
pieces at the same time, and along each
side of the lap joint seam. Select the
wire diameter, heat setting, and tune in
the wire speed in such a way suitable
for welding the material with a
continuous bead
(fig T)
.
(fig V)
.
FLUX-CORE WIRE FEED WELDER KIT 058-8194-4
fig T
.
fig U
fig V
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