From the tubes you drew to the tubes you weld.

Draw the cage as centerlines — lines and arcs on any plane, or in a 3D sketch — pick the die, and every member becomes a walled round tube body: sharp corners filleted at that die's calibrated radius, members split at the junctions, one body each. Click a line and only its member is built; leave the pick empty and the whole wireframe is.

Type X, Y and Z offsets from a reference you picked — the origin, a vertex, a point you placed a moment ago — and real sketch points appear and move as you type, each step drawn along its axis. A mirror column places the cross-car twin with it, and a point can be dropped anywhere along an existing tube, measured down its centerline through the bends.

Pick points in run order and a walled round tube is built through them, cornered at the die's calibrated radius, with the die seeding the OD and wall. Close the loop for a hoop; tick a box for the mirrored twin across the centerline. Bendability is checked while you pick: every straight between bends has to leave the die something to grip, the same rule the export gate enforces, so the fix is a dragged point rather than a refused file.

Move a point a tube was built through — a placed point, an anchor, a sketch point you drew by hand — and run this: every tube built through a moved point is rebuilt in place on its own radius, keeping its name, its identity and its joint records. Ends come back square; run Update Copes and the joints follow. A move that would change the bend count is refused, not guessed.

One button lays a snap-point sketch over every visible tube: its ends, its bend tangents, the middle of each bend where a brace lands on the outside, and each bend's sharp corner — the point a new run needs to rebuild or extend through an existing bend. Shared joints fold to one point. Re-run it after moving tubes; anchors a tube was built through keep their identity.

A tube drawn on the wrong radius is re-cut onto the die you actually own: both ends and every bend corner stay put, and only the tangents, the arcs and the blank length move. It reports first — every bend checked against the die pinned for its OD, blocked tubes listed with the reason — and nothing changes until you tick the rows and apply. Aim a member, bent or straight, at the tubes its ends land on and it re-seats onto their centerlines, the bend angles absorbing the change, every delta previewed before OK.

One button runs every manufacturability check over the whole assembly before anything is cut: grip lengths against the die and the shop's own minimum, copes landing in bend zones, wall features on arcs, stick fit, die matches. It reports tube by tube and changes nothing, and a short grip comes with the exact add-this-much-to-that-end fix.

Select branch tubes and host tubes, and every branch is notched against the tubes it actually meets — in the model, on the bodies you drew. Hosts are never modified; that protection is structural, not a setting. The dialog reopens with hosts still selected, so you work joint by joint without re-picking.

Every cope is normalized to the square two-axis cut a rotary notcher or tube plasma actually makes — a conservative blend by default, with per-end control when you want it. A weld-gap annotation states the worst-case fit-up gap the chosen blend costs, so the welder knows before the tube does.

Pick every tube in the order you would physically install it: the first is the base and is never cut; each later tube copes to everything it touches before it. Work a whole structure in one run, or one joint at a time — and finished joints are never re-cut.

An end that lands on several tubes is coped against all of them, and the joint comes out clean in a single run. A tube that passes through another is recognized and split into two members before the ends are typed — the cut a mid-span trim cannot make.

Every joint is a recorded event. Change the design and click once: every recorded joint is re-cut from the current geometry, in order, as a single undo step.

Tick a box and a cope grows a heel tab; the host it lands on gets a matching slot, sized to the tab plus a set tolerance. Disable a slot and its tab is dropped with it — the record never ships half a joint.

Holes, rectangles, slots and cutouts modelled into the tube wall are carried as first-class features, and physical intent is read from the geometry: a through-hole cuts, while an engraved pocket is scribed rather than cut out, so a part number does not become a row of holes. Every feature can be routed cut, mark or skip at the machine.

The machine scribes what the shop needs to know: saddle marks with assembly step numbers, tube IDs, bend specs, clamp-block marks for the bender in either feed direction, and a datum line for measuring rotations after bending. Machines without a marker can cut their marks instead, with the never-cut categories still protected.

Print-at-actual-size wrap templates, as tiled PDF or DXF. Every page carries a calibration square and a scale bar, so a mis-scaled print is caught before it cuts a tube. Host wraps include the saddle marks with their step numbers.

OD, wall, length, cope angle and depth per end, bevel, and the heel-to-heel clock for double-coped tubes — merged across sessions as you cope joint by joint. Stale rows from undone joints are pruned on demand, never silently. A joint report logs every joint ever cut, with its settings.

Feed, rotation and angle tables, apex points, and a per-tube die spec — driven by a shop die library with a calibrated radius per die and springback recorded the way benders think: the angle you hold against the angle you get.

One STEP or IGES per tube — as modelled, or as a developed blank: the bent tube straightened, cut first and bent after, with the marking curves carried through as geometry.

Tubes group by OD and pack onto sticks, rotated so that copes interleave, with the chuck clamp and the machine dead zone reserved and offcuts reused. A tube that does not fit the usable stick is excluded and named in a warning — never silently placed into the clamp.

Per-stick programs for the common controllers, with kerf carried through the toolpath as a true geometric offset — a drawn 0.375in hole finishes at 0.375in. Lead-in and lead-out, pierce parameters, height-control zones, feed ramp, per-tube program stops. Then a torch simulation runs the program over the 3D blanks in planned machine time, with an A-axis dial and a cycle clock that matches the estimate.

A fidelity check compares each tube record against the modelled body it came from and flags material the record cannot account for — an unmodelled gusset, a feature that was skipped — so the paper never silently disagrees with the design. Per-body reports say exactly why anything was left out.

The design stays in the Fusion document you already have, and everything the pipeline writes — cut list, wraps, bend sheets, nest, G-code, DXF, STEP and IGES — lands on your own disk as ordinary files. No part of the job is sent anywhere to be processed, and none of it is stored on our side.