Tweco 25mm Cutmaster - Manual (Page 42)

CUTMASTER 25MM
OPERATION Manual 0-5080
4T-8
Standoff Distance
Straight Arc
Trailing Arc
Leading Arc
Direction of Torch Travel
A-02586
Mechanized Torch Operation
For optimum smooth surface quality, the travel speed should be adjusted so that only the leading edge of the
arc column produces the cut. If the travel speed is too slow, a rough cut will be produced as the arc moves from
side to side in search of metal for transfer.
Travel speed also affects the bevel angle of a cut. When cutting in a circle or around a corner, slowing down
the travel speed will result in a squarer cut. The power source output should be reduced also. Refer to the
appropriate Control Module Operating Manual for any Corner Slowdown adjustments that may be required.
Piercing With Machine Torch
To pierce with a machine torch, the arc should be started with the torch positioned as high as possible above
the plate while allowing the arc to transfer and pierce. This standoff helps avoid having molten metal blow
back onto the front end of the torch.
When operating with a cutting machine, a pierce or dwell time is required. Torch travel should not be enabled
until the arc penetrates the bottom of the plate. As motion begins, torch standoff should be reduced to the rec-
ommended 1/8 - 1/4 inch (3-6 mm) distance for optimum speed and cut quality. Clean spatter and scale from
the shield cup and the tip as soon as possible. Spraying or dipping the shield cup in anti - spatter compound
will minimize the amount of scale which adheres to it.