Selecting The Proper Amperage; Welding Parameters; Ac Welding; Figure 5: Bead Heat Requirement Samples - Firepower FP-100 Instruction Manual

SELECTING THE PROPER AMPERAGE

The electrode type and thickness of the metal work-piece determine the
amount of heat needed in the welding process. See Figure 5 for bead examples
of heat based on rod size. Heavier and thicker metals require more heat or
amperage. Refer to a rod and amperage guide or experiment on scrap metal.
When you weld with proper rod your results will be:
1. Bead will lay smoothly over the workpiece without ragged edges.
2. Base metal puddle will be as deep as the bead that rises above it.
3. The welding operation will make a crackling sound similar to the sound of
frying eggs.
When you weld with rod that is too small your results will be:
1. Bead will be high and irregular.
2. Arc will be difficult to maintain
When you weld with rod that is too large your results will be:
1. Arc will burn through light metals.
2. Bead will undercut the work.
3. Bead will be flat and porous.
4. Rod may freeze or stick to the workpiece.
The rate of travel over the workpiece affects the weld. To ensure proper penetra-
tion and enough deposit of rod, move the arc slowly and evenly along the weld seam.

WELDING PARAMETERS

Following tables provide recommended welding parameters for various welding jobs using various welding types.

AC WELDING

Alternating current continuously changes polarity.
Ideal Current For:
• Down Hand Heavy Plate.
• Fast Fill.
AWS ROD NO.
E6013 Down Hand
General Purpose Mild Steel
General Purpose
Work on Mild Steel
E7014 New Steel Fabrication
General Purpose
Iron Powder and All Build Up Worn Surfaces
other AC Rods
E6011 Down Hand
General Purpose Mild Steel
General Purpose
Work on Mild Steel
ROD
USE SIZE
1/16"
3/32"
5/32"
5/64"
3/32"
5/32"
5/32"
13
AMPERAGE
Min. - 40 amps
30 - 80 amps
1/8" 70 - 160 amps
120 - 180 amps
30 - 100 amps
40 - 100 amps
1/8" 100 - 170 amps
140 - 150 amps
1/8" 100 -150 amps
120 - 170 amps
Figure 5: Bead Heat Requirement
Samples
METAL
THICKNESS
Min. - 1/8"
1/16" - 1/4"
1/8" - 1/2"
1/4" - Up
Min. - 1/8"
1/16" - 1/4"
1/8" - 1/2"
1/4" - Up
1/8" - 1/2"
1/4" - Up