CNC Logo Cutting Guide: How Markings Survive Metal
This guide explains how a cutter turns a vector logo into a permanent mark on a machined part. It is written for design engineers and buyers who need to pick a depth, a tool, and a material. By the end you can tell whether a logo should be cut, engraved, or printed.
In this article
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What actually happens when a cutter meets a logo
CNC logo cutting is a subtractive marking process. A rotating cutter, usually a V-bit or a small flat end mill, follows the logo contour and removes material to a set depth. There is no ink and no added part. The mark is the same metal as the body, just lower.
That matters for wear. Printed logos sit on the surface and can be rubbed off, chemically stripped, or baked away. A cut logo becomes a small pocket or groove. It stays readable as long as the surrounding surface does.
The cut also changes how light hits the part. A V-groove reflects differently from a flat face, so the logo reads as a line rather than a patch of colour. On brushed or bead-blasted aluminium, this contrast is strongest. On a mirror-polished face it nearly disappears.
Depth is the main variable you control. Too shallow and the mark fades after a light pass with a deburring tool. Too deep and you weaken a thin wall or break through to a cavity. Most industrial logos land between 0.05 mm and 0.5 mm.
- 1V-bitBest for line logos and sharp corners. Typical included angle 60° or 90°.
- 2Flat end millBest for filled shapes and pockets. Leaves a flat floor at a set depth.
- 3Ball noseRounded grooves, softer look. Common on curved or cast surfaces.
Five-axis motion and what it unlocks for curved faces
A three-axis machine cuts straight down the Z axis. On a flat face that is fine. On a curved housing, a cylindrical boss, or a draft-angled wall, the tool meets the surface at an angle, so one side of the groove is deeper than the other.
Five-axis machining rotates the tool or the table so the cutter stays normal to the surface. Sixteen simultaneous five-axis centers at GreatLight are used for exactly this. The groove depth stays constant around a curved logo, even when the surface tilts 40° or more.
The same setup removes the need for multiple fixtures. A logo on three faces of a part can often be cut in one operation, which keeps the registration between faces tight. Re-clamping a part is where position error creeps in.
Not every logo needs five axes. Flat plates, brackets, and most front panels cut fine on a three-axis mill. The extra cost only pays off when the logo wraps a curve or sits on a compound angle.
Preparing the vector file before the first cut
The cutter follows a path, so the logo has to arrive as a clean vector. A raster JPG will be traced by software and the trace will be wrong somewhere. Hairlines, gradients, and drop shadows do not survive the transfer.
Convert all text to outlines. Fonts differ between machines and a substituted font changes stroke width. If the logo has a thin serif, check that the thinnest stroke is at least 0.3 mm wide, or the tool will chatter and tear it.
Set a single line weight for the cut path. Double lines from a traced bitmap produce an island of material in the middle of the stroke. That island can break loose and jam the cutter.
Send the file with the part model, not just the logo. We need to see where the mark sits relative to datums, holes, and walls. A logo placed 0.2 mm from a machined edge may be fine on one part and cut through on another.
- 1Vector onlyAI, DXF, or SVG. No JPG or PNG for the cut path.
- 2Outlined textConvert fonts so stroke width is fixed.
- 3Minimum stroke0.3 mm for V-bit work, 0.5 mm for flat bottom.
Which materials take a clean CNC logo cutting mark
Aluminium is the easiest. Grades like 6061 and 7075 cut cleanly at high spindle speed and hold a crisp edge. Anodising after the cut adds colour to the groove, which raises contrast without any ink.
Stainless takes more care. Grades 304 and 316 work-harden, so a light pass with a dull tool will smear instead of cut. A sharp carbide cutter and a steady feed avoid that. Grade 303 machines more freely because of its sulfur content.
Brass and copper cut beautifully. C36000 brass leaves a bright, well-defined groove that needs no finish. Copper is gummy, so a positive rake tool and a light depth of cut are needed.
Plastics behave differently. PMMA and PC cut cleanly but a deep groove can craze under stress. POM and PEEK hold a fine mark well. Carbon fibre needs a diamond-coated tool or the fibres fray at the edge.
Where CNC logo cutting stops making sense
Very small logos are a problem. Below about 1.5 mm character height, a V-bit cannot produce a readable stroke. Laser marking goes finer and is the better choice there.
Thin walls are another limit. A 0.3 mm deep groove in a 0.8 mm wall removes a third of the section. That is a stress riser and a leak path on a sealed housing. In that case, mark a thicker boss or move the logo to a flat area.
Hardened tool steel above 45 HRC needs a different process. A carbide cutter will cut it, but tool life drops fast and the cost climbs. EDM engraving or laser is more economical at that hardness.
Finally, consider whether the mark needs to be tamper-proof. A shallow cut can be polished out. A cut combined with a serial number and a controlled depth of 0.4 mm or more is much harder to remove without leaving evidence.
Cut depth and tool choice by material
Depth ranges are starting points for a first article, not fixed rules.
| Material | Typical depth | Tool | Watch out for |
|---|---|---|---|
| Aluminium 6061 | 0.1–0.3 mm | 60° V-bit | Built-up edge at low speed |
| Stainless 304 | 0.05–0.15 mm | Sharp carbide V-bit | Work hardening on a dull tool |
| Brass C36000 | 0.1–0.4 mm | 90° V-bit | Burrs on the exit edge |
| Titanium Ti-6Al-4V | 0.05–0.1 mm | Coated carbide | Heat at the tip, slow feed |
| PMMA acrylic | 0.1–0.2 mm | Single-flute cutter | Crazing near a stressed edge |
| POM / PEEK | 0.1–0.3 mm | Flat end mill | Fuzz on the groove floor |
Pick the process by what the mark has to do
For a permanent mark on a curved or load-bearing metal part, cut it with a V-bit and keep the depth under 0.3 mm. For logos below 1.5 mm character height, or on hardened steel above 45 HRC, use laser marking instead.
Common questions
How small can a cut logo be?
A V-bit needs room to reach the bottom of the groove. In practice, character height below 1.5 mm gives strokes that are hard to read and easy to fill with swarf.
Laser marking holds detail down to about 0.5 mm character height, so it is the better route for small marks.
Can the cut be filled with a different colour?
Yes. A common approach is to cut the groove, then anodise the part so the recess takes a different tone from the face. Paint fill is also possible, but it can flake on parts that see abrasion.
On stainless, a black oxide or laser pass after cutting gives a dark mark inside a bright groove.
Does cutting a logo weaken the part?
A 0.1 mm groove on a 5 mm wall is negligible. The risk starts when depth is a large share of the local section, roughly above 20 percent.
On a thin or pressurised wall, move the logo to a thicker boss rather than cutting into the thin area.
What file do you need for a quote?
Send the part model as STEP or IGES and the logo as AI, DXF, or SVG with text outlined. Note the intended depth and the surface finish.
We return a DFM analysis within 12 hours, usually with a note on stroke width if any line is too thin to cut.
Can you match a logo across a curved housing?
Yes. A five-axis setup keeps the cutter normal to the surface, so depth stays constant around the curve.
We cut a first article and check groove depth at several points before running the batch.
Is the mark tamper-proof?
A shallow groove can be polished out by hand. A cut at 0.4 mm or deeper, paired with a serial number, is far harder to remove without visible rework.
For traceability, we can combine the cut with a laser-marked serial and a data matrix code.
Send the logo and the part model
Upload the STEP file and the vector logo. You get a quotation and a free DFM analysis within 12 hours, with a note on depth and tool choice before anything is cut.
12-hour quote100% inspectionNDA on requestNo MOQ
More machining notes from our shop floor
We publish setup notes, tooling trials and inspection data from the factory floor.
