Use profile for the outer boundary of a part, cut-out for an opening through the sheet, pocket for a recessed area and engraving for a shallow line or detail. Then add dimensions, depth and a reference face so the term cannot be misread.
The same circle on a drawing might mean a through opening, a shallow recess, a clearance hole or a decorative mark. Geometry alone is not always a machining instruction.
Profiles and internal cut-outs
A profile operation follows a boundary to create a part perimeter or opening. The cutter may run outside an outer boundary or inside an opening so the finished geometry remains at the intended size. The submitted design should normally describe the required finished shape rather than containing hidden cutter compensation.
Profiles also need a separation plan. The part must remain controlled as the final surrounding material is removed. Tabs, a thin retained layer or another suitable workholding strategy may leave areas that need later cleanup. If an edge is visible or controls a fit, mark it so the hand-off condition can be agreed.
For every profile, identify:
- whether it is the part perimeter or an internal opening;
- the intended finished dimensions;
- the visible face and any grain direction;
- edges that are critical to fit or appearance;
- small pieces or narrow sections that may be difficult to hold.
Pockets and recessed areas
A pocket removes material to a stated depth without cutting through. Pockets can create trays, dados, hardware recesses, locating features or decorative relief.
A pocket definition needs:
- a closed boundary or clearly defined region;
- depth measured from a named face;
- remaining material thickness where relevant;
- an acceptable internal radius;
- the purpose of the floor and side walls;
- finish or hardware that changes the final relationship.
“Make this area lower” is not enough. If a component must sit flush, provide the real component and say whether paint, adhesive or a gasket sits between the surfaces. Deep, narrow pockets also need a cutter that can enter, reach the floor and clear material effectively.
Holes are defined by purpose
A round feature may be profiled, interpolated, drilled with suitable tooling or created as part of another operation. The sensible method depends on diameter, depth, material and required result. CNC routing in sheet material should not be assumed to produce the same result as a reamed metal bore.
Describe what the hole does:
- clearance for a bolt or shaft;
- pilot or location for a later fastening step;
- recess for a screw head or flange;
- passage for a cable;
- location for a dowel or insert;
- decorative opening.
State diameter, centre position, depth, face and actual mating hardware. Nominal hardware names can hide different body, head and installation dimensions.
Slots, dados and grooves
A slot is a narrow elongated feature. A dado or housing commonly receives the edge of another panel. Width, length, depth, end shape and insertion direction all matter.
A round cutter leaves radiused ends and corners. A square-ended tab may need rounded corners, an intentional relief or a different joint. Slot width should follow actual material and required assembly behaviour rather than only the nominal sheet label.
Use the joints and fit guide when a slot locates another part. Use the internal-corner guide when seating is blocked by a cutter radius.
Engraving and line work
Engraving follows a line or removes a shallow region to create lettering, marks or decoration. Its appearance depends on cutter geometry, depth, material surface, line spacing, text size and finish.
Specify what matters most:
- exact wording and spelling;
- line position or overall appearance;
- required legibility at the intended viewing distance;
- final size of the artwork;
- whether the engraving remains visible after coating;
- whether a hidden part ID is acceptable.
Converting text to outlines preserves geometry but does not make small strokes machinable. Proofread first and keep a readable reference alongside the vector. Representative material testing is more useful than a universal minimum text-size claim.
Through, blind and face orientation
A through feature removes the full material thickness. A blind feature stops at a depth. A top view may show the same outline for both, so add a section view wherever depth or remaining thickness matters.
Each operation should answer:
- Does it pass through the sheet?
- If blind, what is the depth and reference face?
- Which face is presented for machining?
- Which face remains visible?
- Is a second-side setup required?
Operations on opposite faces need an unambiguous Face A/Face B convention and common datums. Do not rely on the direction from which a CAD model happens to be viewed.
A useful operation schedule
For a small organiser side, the drawing could include:
| Feature | Operation intent | Important note |
|---|---|---|
| Outer boundary | Outside profile, through | Visible edge will be prepared later |
| Two shelf locations | Blind pockets | Depth from inside face; fit needs testing |
| Cable opening | Internal cut-out, through | Internal radius can change within marked limit |
| Part ID | Shallow engraving | Hidden after assembly |
This schedule connects paths to intent and exposes additional depths, faces or cutter requirements before quotation.
Features that need extra review
- A pocket has no depth or reference face.
- A thick drawing stroke is being used to imply slot width.
- A circle is shown without its hardware or purpose.
- The design does not distinguish inside and outside profiles.
- Engraving contains fine counters or narrow gaps.
- Features on opposite faces must align.
- A final profile releases a small or fragile part.
- A pocket leaves little material for the intended use.
- Several operations use different depths without a clear reason.
When a feature is still open to change, explain the desired outcome instead of prescribing an operation. The review can then compare feasible machining routes without losing the requirement.
Drawings and files to prepare
Supply a vector file for paths and a readable PDF for dimensions and operation notes. Include top and section views, stated units, depth labels, part IDs, material, quantity and current revision. Mark critical dimensions, visible faces and actual hardware.
The standard service quotation defines exactly which operations and post-machining stages are included. Assembly, finishing and packing are not implied merely because the geometry can be machined.
Machining feasibility also does not establish structural capacity or product compliance. If a pocket, hole or remaining wall has a safety consequence, the design needs evidence appropriate to that use.
Send the marked-up part, or use the DXF and SVG preflight before submitting technical files.