Tweco 250i Transmig Inverter - Manual (Page 65)

BASIC WELDING TRANSMIG 250I
Manual 0-5187 4-9 BASIC WELDING
Gap varies from
1.6mm to 4.8mm
depending on plate thickness
Joint
Open Square Butt
1.6mm max
1.6mm
Single Vee Butt Joint Not less than
70°
Double Vee Butt Joint
1.6mm
Lap Joint
Tee Joints
(Fillet both sides of the
joint)
Edge Joint
Fillet Joint
Corner Weld
Plug Weld Plug Weld
Not less than
70°
Single Vee Butt Joint
Not less than
45°
1.6mm max
Art # A-10347
Figure 4-19: Typical Joint Designs for Arc Welding
Arc Welding Technique - A Word to Beginners
For those who have not yet done any welding, the simplest way to commence is to run beads on a piece of scrap plate.
Use mild steel plate about 6.0mm thick and a 3.2mm electrode. Clean any paint, loose scale or grease off the plate
and set it firmly on the work bench so that welding can be carried out in the downhand position. Make sure that the
work clamp is making good electrical contact with the work, either directly or through the work table. For light gauge
material, always clamp the work lead directly to the job, otherwise a poor circuit will probably result.
The Welder
Place yourself in a comfortable position before beginning to weld. Get a seat of suitable height and do as much work as
possible sitting down. Don't hold your body tense. A taut attitude of mind and a tensed body will soon make you feel
tired. Relax and you will find that the job becomes much easier. You can add much to your peace of mind by wearing
a leather apron and gauntlets. You won't be worrying then about being burnt or sparks setting alight to your clothes.
Place the work so that the direction of welding is across, rather than to or from, your body. The electrode holder lead
should be clear of any obstruction so that you can move your arm freely along as the electrode burns down. If the lead
is slung over your shoulder, it allows greater freedom of movement and takes a lot of weight off your hand. Be sure
the insulation on your cable and electrode holder is not faulty, otherwise you are risking an electric shock.