2D Dynamic

Click a flat face or an edge loop and it becomes a machined region — a face's inner loops stand as islands automatically. One pick button handles faces, edges, and sketch curves; hold Shift to build a chain edge-by-edge (it joins the cut the moment it closes). A green overlay always shows exactly the material the operation will clear, so there's no guessing.

Every region gets the same direction arrow as Contour: it knows which side the material is on — a pocket floor machines inside, a part's top face machines the stock around it — and one click on the arrow, or the ⇆ in the dialog, flips inside ↔ outside with the overlay updating live. When only one side makes sense, the arrow steps aside.

Flip a region outside and 2D Dynamic clears everything from that loop out to the stock edge. It knows the space beyond the stock is open air, so the tool enters from the air with no helix ramp — feeding straight into the material edge. Pick two bosses and both stand as islands in one continuous clearing pass.

Every pick knows its own depth: a pocket floor cuts to that floor, a pocket rim reads the depth from its walls, and an outside clear around a boss ends where the boss ends. Pick a −0.25" pocket and a −0.50" pocket in the same operation and each stops at its own floor, with its own stepdown ladder. The overlay sits right on the face you clicked, and the Bottom height always starts from your selection — override or offset it any time.

The Leads tab decides how the tool gets into closed material. The default helical ramp takes a gentle spiral down — set it by angle or by exact pitch (Z drop per revolution), whichever way you think about it — and if you ask for a helix wider than the tool can clear, it clamps to the largest safe diameter and says so right in the dialog, so an entry never leaves a core of stock standing. Prefer to go straight in? Straight plunge drops at the entry point at your plunge feed. Or choose the drilled entry: the tool peck-drills the entry spot first — partial or full retract, with your peck depth — exactly like a Drill operation, then clearing takes off from the drilled hole. Regions that reach the stock edge still enter from open air with no lead at all.

Between passes the tool would rather not go anywhere near clearance height, and mostly it doesn't — it lifts a hair off the floor and flies straight to where the next pass begins. But it will climb all the way up and plunge back in whenever the jump is a long one, even when the whole route crosses material it has already cleared. On a plate with a couple of holes in it, that accounts for the large majority of the full retracts you see in the backplot, and none of them are necessary.

Switch on Keep tool down on the Clearing tab and the route itself decides. The tool stays at link height wherever the path between two passes is genuinely clear of the part and of uncut stock, and comes up only where it truly cannot get through — an island in the way, or fresh material it would have to cut through sideways to get across. Expect fewer retracts, much less plunging, and a noticeably shorter cycle on parts with a lot of separate pockets or islands.

Every link is real geometry, not just a straight jump. The tool peels out of the cut on a small tangent arc — every lead arc in the program shares one tight, load-sized radius — flies a straight high-feed leg, and rolls back into the next pass on a matching arc. Where a single arc can't point the tool cleanly, say leaving a cut that ends against an island, it turns through a compact two-arc S instead, and the leg keeps honest daylight from walls rather than scraping past them. A link that truly can't fly at depth hops just above the stock and drops back in, instead of climbing all the way to clearance; a whisker of stock standing in an otherwise clear corridor is simply shaved on the way past at cutting feed. And every descent back into the cut lands on a rounded blend and a lead-in arc — never a bare plunge straight into full-feed cutting.

It's off by default, and set per operation. Turn it on and watch the retracts in the backplot: the grey dashed lines become the yellow linking moves that stay down in the cut. When a link does lift off the floor, the rise and the descent are blended into small rounded corners the machine can carry speed through — at any lift height, right down to a ten-thou hop — instead of stopping dead twice per link.

The cutter never slams to full load. Every pass tapers its load in: the bite starts at 10% of your optimal load and grows to full over 2 tool diameters of cutting — at the helix exit, at every re-entry, at every link — so the spindle loads up on a ramp instead of taking a torque step you can hear. It's the toolpath itself that changes (the passes start tighter together and spread to the full stepover), not a feed override: the machine cuts at full feed the whole time, nothing is left behind, and it costs almost nothing in cycle time. On by default in Automatic mode, where the taper sizes itself to the tool; flip Automatic off on the Clearing tab to set your own starting percentage and distance, or switch Taper load in off for instant load.

Dead-end features that narrow down toward the cutter — sprocket and pulley tooth valleys, keyway flanks, tight bays between bosses — machine all the way down to the deepest point the tool geometrically fits. The cutter works these features the same way it clears everything else: descending rung by rung at your set load, following the true wall, until the walls themselves close on the tool. Nothing is left standing that the cutter could have reached, so a following Rest machining pass only ever sees material the tool genuinely cannot enter — and on many parts, that's nothing at all.

Drop an optional start point and clearing begins there — inside a pocket it places the entry; outside the stock it's where the tool first touches down. The same optimal-load control as the Router keeps the bite constant — percent of diameter or a fixed width, linked both ways — alongside path tolerance and, on the Advanced tab, the smoothing pipeline — the walked path is splined smooth, then fitted as true arc moves against that curve rather than against the raw walk: over 99% of the cut posts as arcs, corners included, with no runs of tiny line segments — when you want the details. Multiple depth passes, stock to leave, and finish walls are all included. To clean up what a big tool couldn't reach, chain a Rest machining pass after it.