RockCAM machines in this order: roughing → holes → finishing (or semi-finishing) → chamfering → tapping. Each stage has its own preferences, and this page covers the ones that change the result most.
Every setting here has a sensible default. The defaults reflect general practice, not your practice — change the ones that do not match how your shop works.
Workholding #
RockCAM starts from Auto, which chooses between a vise and clamps based on the part shape.
The workholding selector with Auto, vise, clamps, vacuum and tape.
You can also set it explicitly:
| Workholding | What it does |
|---|---|
| Vise | Grips the part. Leaves a gripping band in the blank settings. Through holes are drilled right through; the outer profile drops 0.3–0.5 mm below the top |
| Clamps | You specify the clamp positions; the outer profile toolpath avoids them |
| Vacuum chuck | Like a vise, except through holes are not drilled through on OP1, and open pockets are lifted slightly |
| Double-sided tape | Like a vise, except the outer profile stops short first — so the tool does not cut the tape — and a final pass releases the part |
How the program is grouped #
RockCAM creates the program groups as it programs; you do not need to create them first. Three layouts are built in.
One group per OP, with the operations side by side underneath it.
One group per OP, with adjacent operations that share a tool nested together.
All OPs in a single group, with adjacent operations that share a tool nested together.
Machining only part of the part #
By default every stage is selected, so RockCAM machines the whole part: outer profile, faces, chamfers and threads. To machine only part of it — holes only on a part whose outside is already done, no chamfering, no tapping because it will be done by hand — clear the stages you do not want. RockCAM leaves the cleared stages out entirely.
The stage checkboxes under “machining content”, with some cleared.
Roughing allowance and the largest roughing tool #
Roughing needs a floor allowance and a wall allowance. RockCAM applies these to the operation templates, so every roughing operation uses the same allowance.
You also set the largest diameter you want used for roughing — normally your most-used flat or ball cutter, but not a face mill. RockCAM will not pick a tool larger than this, and within the limit it tends to pick as large as the geometry allows: for a 10 mm slot it will reach for an 8 or a 6, not a 4.
The roughing allowance fields and the maximum roughing tool diameter.
Overall and outer-profile roughing #
RockCAM works from the top down: top face, then outer profile, then pockets and holes. It does not rough feature by feature. It reads several features together and picks an overall roughing approach — 3D adaptive or cavity milling, sometimes contour roughing for the outside with 2D strategies for the pockets.
If your habit is always to start with 3D adaptive, you can force it. A part can genuinely be roughed several ways; these settings pick which one OP1 uses.
Roughing with planar or floor-and-wall milling, descending in a contour spiral.
OP1 forced to cavity milling for the whole part, with cavity-mill rest roughing after it.
OP1 forced to adaptive roughing, with cavity-mill rest roughing after it.
Facing #
Facing is the top face of the blank, normally roughed and finished with a face mill. The defaults use a face mill and separate the roughing pass from the finishing pass, using the roughing floor allowance set earlier.
The facing settings, showing the tool choice and the separate roughing and finishing passes.
Chamfering #
RockCAM chamfers two things: a chamfer face drawn in the model, which must be a 45° face against a flat, and a sharp right-angled edge next to a flat. Both are chamfered by default. A drawn chamfer face is cut to match; a sharp edge is cut to the value you set, 0.3 by default.
The operations it produces are 2D planar chamfering for pockets, and G81 spot drilling for small holes.
The chamfer settings page, showing the default chamfer size for sharp edges.
The resulting 2D chamfer toolpath along a pocket edge.
The G81 spot-drilling chamfer toolpath on a group of small holes.
You do not need to decide which strategy applies where. RockCAM picks the tool and the strategy, and it runs a collision check as it does so:
- It checks edges to keep the tool clear, and will skip a chamfer rather than collide.
- It checks step depth and lifts the tool so it does not cut into a step.
- It increases the chamfer on threaded holes according to the size of the thread.
- If a chamfer face is larger than the amount you allow, it takes it in several passes.
The full set of chamfer options, including the cut-off that decides between a chamfer tool and surface finishing.
One setting matters more than the rest: use a chamfer tool only when the chamfer is smaller than this value. On a drawing, some chamfer faces are too large for a chamfer tool; above the cut-off RockCAM uses Z-level profiling instead and sweeps the face. That covers large chamfers, chamfers outside the C-angle convention, and radii — radii are always swept, never cut with a radius tool.
A large chamfer finished by Z-level profiling instead of a chamfer tool.
Set that value to 0.01 to sweep everything and never use a chamfer tool.
Finishing the floor and the wall separately #
A pocket with flat floor and walls can be finished with planar milling or cavity milling. Normally RockCAM may finish the floor and the wall together, or the floor first and then the wall.
The setting that finishes the floor before the wall.
With the setting on, RockCAM finishes the floor first and leaves the wall for the second pass. That suits parts with a tolerance on the floor.
The floor finished while the wall still carries stock.
The second pass finishing the wall, bringing both floor and wall to size.
With the setting off, the two are usually combined. That is not a promise: on a deep wall, or one with slopes, RockCAM separates them anyway.