Learn/Oxyfuel/Toolpath Generation & Post-Processing
Toolpath Generation
Updated v2.4.4At a glance
- Kerf compensation, leads, tabs and cut ordering all work as they do in Plasma
- Every lead-in creeps into the plate before winding up to cutting speed
- Creep feed and distance are per-thickness cut chart values
- Small holes get extra wall clearance before switching to a centre pierce
- Arcs stay arcs — G2/G3 preserved end to end, never linearized
- Kerf width comes from the tip chart row, not from an arc voltage
- Contour rules, scribing and simulation carry over unchanged from Plasma
Oxyfuel toolpath generation is the Plasma generator with the flame-specific behaviour it needs. Kerf compensation, lead-in and lead-out, tabs, cut ordering, contour rules, scribe layers and cut simulation all behave exactly as they do in Plasma. Two things differ, and both matter on the plate.
The creep lead-in
A flame torch will not take full cutting speed the instant it starts moving — the kerf has to establish first or the cut wanders and can fail to sever. So the start of every lead-in runs at a slow creep feed, then accelerates to the chart's cutting speed for the rest of the contour.
Both the creep feed and the creep distance are cut chart values, because how far and how slowly you ease in scales with plate thickness like everything else. Leave them blank on a chart row and the post's own defaults apply to every thickness; set them on a row to override that thickness. Set the creep distance to 0 to turn the creep off entirely.
The creep applies to the toolpath itself, not to the gas — it is ordinary feed control in the posted program, so it works on any controller.
Small holes and the centre pierce
A plasma pierce is near-instant and blows a hole roughly the width of the kerf. A flame pierce dwells for seconds and craters considerably wider. That changes which holes can safely take an arc lead-in.
Oxyfuel therefore demands more wall clearance than plasma before it will run an arc lead into a circular hole, and switches to a centre pierce sooner — pierce at the safe centre of the hole, then ease out to the wall on a tangent fillet. A hole that plasma would lead into normally may centre-pierce here, and that is deliberate: the alternative is burning through the wall.
As in Plasma, JetCad3 asks once per generation whether to override small holes to centre pierces or keep arc leads on everything, and remembers your answer.
Kerf
Kerf width comes from the tip chart row for the plate being cut. There is no arc voltage feeding into it and no height control adjusting it mid-cut — the tip and the thickness determine the kerf, and the chart carries it.
Arcs
Arcs are preserved as true G2/G3 moves the whole way through, never flattened into line segments, exactly as in Plasma and Laser. The post decides the final form.
Related: Torch Selection & Cut Charts, G-code Post Processor.