Tweco SL100 - Manual (Page 28)

OPERATION 4-4 Manual 0-2962
E. Dross
When dross is present on carbon steel, it is com-
monly referred to as either “high speed, slow speed,
or top dross”. Dross present on top of the plate is
normally caused by too great a torch to plate distance.
"Top dross" is normally very easy to remove and can
often be wiped off with a welding glove. "Slow speed
dross" is normally present on the bottom edge of the
plate. It can vary from a light to heavy bead, but does
not adhere tightly to the cut edge, and can be easily
scraped off. "High speed dross" usually forms a nar-
row bead along the bottom of the cut edge and is very
difficult to remove. When cutting a troublesome steel,
it is sometimes useful to reduce the cutting speed to
produce "slow speed dross". Any resultant cleanup can
be accomplished by scraping, not grinding.
4.07 Hand Torch Operation
A. Standoff Cutting With Hand Torch
NOTE
For best performance and parts life, always
use the correct parts for the type of operation.
1. The torch can be comfortably held in one hand
or steadied with two hands. Position the hand to
press the Trigger on the torch handle. With the
hand torch, the hand may be positioned close to
the torch head for maximum control or near the
back end for maximum heat protection. Choose
the holding technique that feels most comfortable
and allows good control and movement.
NOTE
The tip should never come in contact with the
workpiece except during drag cutting opera-
tions.
2. Depending on the cutting operation, do one of the
following:
a. For edge starts, hold the torch perpendicular
to the workpiece with the front of the tip on the
edge of the workpiece at the point where the
cut is to start.
b. For standoff cutting, hold the torch 1/8 - 3/8 in
(3-9 mm) from the workpiece as shown below.
A-00024_AB
Shield Cup
Torch
Standoff Distance
1/8" - 3/8" (3 - 9mm)
Standoff Distance
3. Hold the torch away from your body.
4. Slide the trigger release toward the back of the
torch handle while simultaneously squeezing the
trigger. The pilot arc will start.
A-02986
Trigger
Trigger Release
5. Bring the torch within transfer distance to the work.
The main arc will transfer to the work, and the pilot
arc will shut off.
NOTE
The gas preflow and postflow are a character-
istic of the power supply and not a function of
the torch.