Tweco CutMaster 101 with SL100SV - Manual (Page 49)

Manual 0-4642 4-9 OPERATION
4
4.05 General Cutting Information
WARNINGS
Disconnect primary power at the source before disassembling the power supply, torch, or torch leads.
Frequently review the Important Safety Precautions at the front of this manual. Be sure the operator is equipped
with proper gloves, clothing, eye and ear protection. Make sure no part of the operator’s body comes into contact
with the workpiece while the torch is activated.
CAUTION
Sparks from the cutting process can damage coated, painted, and other surfaces such as glass, plastic and metal.
NOTE
Handle torch leads with care and protect them from damage.
A. Piloting
Piloting is harder on parts life than actual cutting because the pilot arc is directed from the electrode to the tip
rather than to a workpiece. Whenever possible, avoid excessive pilot arc time to improve parts life.
B. Torch Standoff
Improper standoff (the distance between the torch tip and workpiece) can adversely affect tip life as well as
shield cup life. Standoff may also significantly affect the bevel angle. Reducing standoff will generally result in
a more square cut.
C. Edge Starting
For edge starts, hold the torch perpendicular to the workpiece with the front of the tip near (not touching) the
edge of the workpiece at the point where the cut is to start. When starting at the edge of the plate, do not pause
at the edge and force the arc to “reach” for the edge of the metal. Establish the cutting arc as quickly as possible.
D. Direction of Cut
In the torches, the plasma gas stream swirls as it leaves the torch to maintain a smooth column of gas. This swirl
effect results in one side of a cut being more square than the other. Viewed along the direction of travel, the right
side of the cut is more square than the left.
Right Side
Cut Angle
Left Side
Cut Angle
A-00512
Scrap
Clockwise
Counter-
Clockwise
Art # A-04182
Workpiece
Scrap
Side Characteristics Of Cut
To make a square - edged cut along an inside diameter of a circle, the torch should move counterclockwise around the circle.
To keep the square edge along an outside diameter cut, the torch should travel in a clockwise direction.