3
Completing the cut
One of the following techniques may be necessary on metal
5 inches (125 mm) thick or greater to fully complete the cut.
Otherwise, the arc may jump the very bottom portion of the
cut as it exits the edge of the metal or enters the kerf,
resulting in an incomplete sever of the cut piece.
Exiting the edge of material (lead-out speed)
For cuts that involve the arc exiting the edge of the material
(as shown in Figure 2), a reduced cut speed should be used
for the last 1 inch (25 mm) of the cut. The recommended
final cut speed should be 75% of the full cut speed. The
cutting table must continue motion beyond the edge of
the plate.
Figure 2 – Lead-out exiting the edge of the material
External contour part cut (dogleg or acute angle lead-out)
The dogleg (or acute angle) lead-out technique can be used
to redirect the tail of the arc and the molten metal flow into
the remaining portion of the cut (or “tab”), thereby allowing
for a complete cut (see Figure 3 and Figure 4).
1 Follow the edge start, lead-in, and cornering
recommendations previously listed.
2 Cut the external contour of the part and approach lead-out.
3 Just as the arc breaks through to kerf, change the cut
direction by approximately 120 degrees into the skeleton at
115% of the cut speed.
4 Continue the lead-out segment for approximately
1.25 inches (32 mm) – the molten metal flow from cutting
into the skeleton melts the tab, which completes the cut and
allows the part to “drop.”
Dogleg lead-out details are included in the Dogleg lead-out
details for thick stainless steel section in this document.
Figure 3 – Example of dogleg lead-out programmed cut path Figure 4 – 6 inch (150 mm) “dropped” external
contour cut
Dogleg lead-out region
Lead-in
Part
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