3D model roughing

Clear above the model one depth at a time

Roughing uses the evaluated solid selected in Model setup. Choose Whole body for all accessible upper surfaces, or Selected faces to limit the machining area. Camera orbit changes the view; Cutter Z sets the machining direction.

At each depth, Cadivari protects the model material at and above that level, including higher slopes and raised islands. The boundary is expanded for the flat end mill and allowance. The remaining area receives boundary passes and an X- or Y-direction raster.

Tool centres stay inside the projected model footprint, or the selected faces when using Selected faces. The cutter can extend beyond that footprint, but must fit completely within the configured stock. This clears excess stock above the body; it does not clear the surrounding stock all the way down to the model bottom. Through openings and inaccessible narrow details require separate operations.

The strategy needs a flat underside and an upper surface accessible from the selected cutter direction. Overhangs and downward-facing surfaces above the base are blocked. It does not machine undercuts.

Choose the faces to machine

1. In CAM → 3D Model, choose Roughing → Selected faces.
2. Click an upward-facing flat or curved surface. Amber shading and an outline show the selection. Click more faces to add them; click a selected face again to remove it. No modifier key is needed. Clear selection removes all picks.
3. Orbit or use Top to inspect the area, then choose Add model roughing. The button is disabled until at least one supported face is selected.
4. To change an existing operation, open its Operations card and choose Edit machining area. Change the picks or switch to Whole body, then choose Apply machining area. This updates that operation and preserves its cutter and cutting settings.

The selected faces define a cutter-centre boundary in the machining XY plane. The cutter radius can overlap its edges; selection does not promise that all neighbouring stock remains untouched. Separate selected areas stay separate, and openings are excluded. Depth layers stop at the lowest selected upper surface plus allowance, subject to cutter access. The surrounding body is still protected at every depth.

Vertical walls and undersides cannot be selected in the current Cutter Z direction. Smoothly connected curved mesh strips are picked as one patch; sharp seams separate patches. Existing projects keep their Whole body target until you explicitly change it. Face selection does not remove the strategy's accessibility or finishing-stock requirements.

Depth and spacing with material to leave

Stepdown sets the maximum depth increment from stock-top Z0. The last useful layer may be shallower. Layers that cannot contain the cutter near the bottom of the surface are omitted; Lowest cut Z reports the actual deepest generated cut. To clear stock above the model's highest point, set Stock above model in Model setup and fit the stock.

Stepover is 5–90% of cutter diameter. Smaller values create closer raster lanes and more motion. Along X runs lanes in setup X and steps in Y; Along Y does the reverse.

Allowance leaves 0–10 mm radially and vertically around the model. Its meaning differs from the ball-nose Surface operation's offset around the surface. Slopes, tool reach into details and depth terraces can leave more stock than the entered allowance. A small additional numerical guard protects path approximation and output rounding.

Feed sets the clearing feed. Plunge sets the entry feed, including the approach to stock top, ramp moves, the return along the entry path at target depth, and any vertical plunge. Spindle is the manual router speed target. Choose a centre-cutting end mill suited to the chosen entry, and review tool reach.

Ramped entry along the clearing path

Entry → Ramp descends along a portion of the already compensated clearing path. The complete cutter remains outside the protected model. Shorter paths use repeated back-and-forth traversals; the cutter retraces the same bends on its return, then completes the original clearing pass at target depth.

Angle is the maximum descent angle from horizontal, between 1° and 15°; new operations start at 3°. The planner may use a shallower angle to limit the drop on each reversal. Each traverse descends by at most half the Stepdown, limiting the depth difference between repeated visits. This does not calculate cutting load or guarantee a suitable angle for a particular tool or material.

Each required ramp begins at stock-top Z0. This implementation does not assume an entry well has already been cleared by earlier depth layers. It can add travel and machining time, especially in deeper layers. A verified cleared-space connection replaces the lift and entry entirely; other transfers still use a full Safe Z lift.

Short paths → Stop is the default. A ramp must have at least one cutter diameter of path length and spread; tiny lanes or loops cannot be used as almost vertical ramps. Repeated-entry and total-motion limits also prevent excessive work. If an entry cannot fit, the operation reports Entries blocked and blocks playback and G-code output. Changing raster direction, cutter size, angle or stepdown can help, depending on the cause.

Short paths → Allow plunge explicitly permits a vertical entry on paths that cannot fit a ramp. The operation displays Plunge fallbacks and a warning, and G-code records the count. Inspect these moves in Simulate → Toolpaths and use a centre-cutting end mill suitable for plunging. No paths are silently skipped.

Entry → Plunge uses vertical entry for paths without a verified connection. Projects saved before ramped model roughing keep that setting when opened; select Ramp to change an existing operation. Entry settings and fallback choices are saved with the project.

Connect through verified cleared space

Connections → Cleared space links nearby consecutive paths at the same depth when the complete flat-end-mill sweep fits inside material already removed by this operation. The planner checks completed cutting paths, not just the model outline, the two endpoints or the line between cutter centres. An uncut island or gap therefore retains the Safe-Z transfer.

A connection can retrace a previously cut boundary or cross the combined area of several completed cutter sweeps. Verification includes rounded output coordinates and conservative geometric margins. Only connections no longer than three cutter diameters are considered. If the proof is uncertain or exceeds the processing budget, Cadivari retains the original lift and entry.

Links are constant-depth G1 feed moves at the operation's Feed setting. They are shown in a distinct colour, labelled LINK during playback and identified in G-code comments. Cleared-space links reports how many transfers were replaced; Safe-Z transfers counts the remaining transfers between paths, excluding the initial and final lifts. Time estimates use the resulting moves.

The first path, every new depth layer, long or unverified transfers, and the end of the operation retain Safe Z. Clearance is not borrowed from another operation, another tool or material removed at a shallower depth. The planner does not reorder the cutting paths or search for routes around obstacles. Holder and fixture clearance still depend on the real setup.

Connections → Safe Z restores a full lift and entry between every path. Older projects retain this setting; new roughing operations start with Cleared space. The choice supports Undo/Redo and save/open. Changing it recalculates the motion immediately. A short path reached through verified cleared space needs no new ramp; short-path fallback applies only where an entry remains necessary.

Rough and finish before cutting the outside contour

A new model roughing operation is inserted before the first Surface or outside contour operation. Review the complete job order: model roughing removes bulk stock, ball-nose Surface finishes the top, and the outside contour separates the part. Place any other internal machining before the separating cut.

Simulate → Material begins with the configured rectangular stock. Complete-job playback accumulates removal across operations and uses the assigned cutter shape. Toolpaths, playback, time estimates and G-code share the same generated moves. The combined output includes the required cutter stages.

Roughing does not automatically establish that a finishing pass has acceptable engagement. Inspect the remaining terraces and narrow areas before finishing; reduce roughing stepdown or choose another cutter if needed. Review tool reach and the export preflight before machining.

Inspect the stock left for finishing

Open Simulate → Remaining stock and choose After roughing. Yellow and orange highlight sampled material above the target, including terraces that exceed the nominal allowance. Compare with After finishing to see what Surface removes. The view includes earlier enabled operations and reports its overview grid size. See Remaining stock for the colour scale and limits.

Regenerate after model or setup edits

Editing the evaluated body, stock, placement, Cutter Z or work origin invalidates the operation's saved generation stamp. Output and model simulation block until Regenerate model roughing updates the paths. Finishing and contour operations have their own regeneration controls.

Cutter, raster direction, stepdown, stepover, allowance, entry angle, fallback and connection changes recalculate directly. Setup and operation changes support Undo/Redo and project save/open. A missing or different setup body cannot silently replace the linked body.

Selected face references are saved with the operation. Setup rotation and placement retain those references, but still require regeneration. If an edit changes, splits or removes a selected face, regeneration blocks and asks you to pick the faces again through Edit machining area. Changes to the evaluated mesh can also require reselection. Cadivari does not silently replace a missing selection with Whole body. Switching to Whole body is an explicit choice.

Current limits

• One setup body, one fixed cutter direction, and a flat end mill. Choose Whole body or up to 128 accessible flat or curved faces; custom sketch boundaries are not included.
• Clearing above the model footprint only; external stock, through holes and unreachable detail need suitable separate operations.
• No rest machining, stock-aware engagement calculation, adaptive toolpaths or automatic finishing-load verification.
• No helical entry, links between depth layers or links between separate operations. Model Surface finishing retains its separate vertical-approach strategy.
• No holder, clamp, fixture, other-body or machine-envelope collision model. Check the physical setup with the CAM safety checklist.
• Paths follow the evaluated triangle mesh with linear moves. Complexity limits block excessive model detail, depth layers or raster density; increase stepdown or stepover, choose another cutter, or simplify the model.