01
Hole walk on curved or angled surfaces
A standard twist drill enters a convex or sloped face and the tip slides before it bites. The hole lands 0.2–0.5 mm off position, the bolt no longer lines up, and the assembly gets reworked or scrapped.
CNC Drilling
CNC Drilling for Precision Parts
Holes, threads and counterbores on small and mid-size batches. We review your DXF or STEP file, check depth-to-diameter ratio and exit conditions, then quote in 12 hours with a DFM note.
Ø0.5–80 mm holes±0.005 mm100% inspectionNo MOQ12-hour quote
127High-precision CNC machines
±0.005 mmAchievable hole tolerance
15 yearsDrilling and milling since 2011
99.99%Qualification rate before shipment
Common problems
Where the process goes wrong
Four failures that show up on the shop floor, not in the model.
02
Burrs on the exit side
Breakout burrs on a hydraulic manifold or a sliding fit block cost you deburring time and can block a passage. On thin walls the drill can also push material out instead of cutting it, so the exit face has to be milled back.
03
Deep holes that drift
Past a 5:1 depth-to-diameter ratio, chip evacuation becomes the limiting factor. Coolant cannot reach the tip, heat builds up, and the hole ends up tapered or out of round by the time it breaks through.
04
Position that changes between parts
One good first article does not prove a batch. Fixture wear, thermal growth and tool changes move hole centers over a 500-piece run, so parts 400–500 fail a go/no-go gauge check at final inspection.
How we run it
Fixturing, tool path and inspection
Three decisions that decide whether the holes repeat.
Setup
Rigid fixturing before the first hole
Most hole position errors come from the setup, not the spindle. We clamp on a machined face or a dedicated soft jaw so the part cannot shift under thrust, and we spot-drill every location before the full-diameter tool touches the workpiece. On curved or angled surfaces we use a spot drill with a point angle matched to the following drill.
For a part with 30 or 40 holes, we often drill on a 3-axis or 4-axis machine with a rotary table and one work offset. Five-axis positioning is reserved for holes on compound angles that would otherwise need a second setup.
- 1Spot drillingEvery hole is centered before full-diameter cutting.
- 2One setup where possibleFewer re-clamps means fewer datum shifts.
- 3Matched point anglesSpot and drill geometry are paired to the material.
Cutting parameters
Speed, feed and peck depth by material
Drilling parameters change with material, not with the machine. A 6 mm hole in 6061-T6 runs at high surface speed with a light peck. The same hole in 316L stainless runs slower with more coolant and a shorter peck cycle, because work hardening at the tip will dull the margin in a few holes.
For holes deeper than 5× diameter, we switch to a through-coolant drill or a gundrill on a vertical deep-hole machine. For interrupted cuts in castings, we reduce feed at the entry and exit to keep the insert from chipping.
- 1Peck cyclesSet by depth-to-diameter ratio, not by habit.
- 2Through-coolantUsed past roughly 5× diameter.
- 3Reduced feed at entry and exitProtects the tool on cast skins and cross-holes.
Selection guide
Which method fits your hole
Match the feature to the process before you ask for a quote.
| Feature | Recommended method | Typical limit |
|---|---|---|
| Hole up to 5× diameter | Standard twist drill, spot first | Ø0.5–80 mm |
| Hole 5×–20× diameter | Through-coolant drill, peck cycle | Straightness within 0.05 mm |
| Hole over 20× diameter | Gundrilling on deep-hole machine | L/D up to 30:1 |
| Hole on a compound angle | 5-axis positioning, one setup | Angles 0–90° |
| Threaded hole | Drill, then tap or thread mill | M1.6 and up |
| Counterbore or spot-face | Drill, then flat-bottom or piloted tool | Flatness 0.02 mm |
Capabilities
Drilling plus what comes after
Most parts need more than a hole. These are the operations we run in the same shop.
01
CNC drilling
Ø0.5–80 mm holes, spot drilling, peck cycles, counterbores and spot-faces on 3-axis, 4-axis and 5-axis machines.
02
Tapping and thread milling
Cut and form taps from M1.6 up, plus thread milling for large diameters and thin-wall parts where a tap would distort the hole.
03
Milling and turning
Faces, pockets and slots around the drilled features, and turned diameters on the same part from mill-turn centers.
04
Deep-hole drilling
Vertical deep-hole machines for long, straight bores in manifolds, mold plates and hydraulic blocks.
05
Deburring and edge work
Manual and tumbled deburring, chamfering of hole entries, and controlled edge break on breakout faces.
06
Finishing
Anodizing, plating, black oxide, bead blasting and laser marking, with masking around critical holes where needed.
Scope
Drilling capacity and what is included
| Item | Range or detail |
|---|---|
| Hole diameter | Ø0.5–80 mm |
| Position tolerance | ±0.005 mm on critical hole patterns |
| Maximum part size | 4,000 mm |
| Depth-to-diameter ratio | Up to 30:1 with gundrilling |
| Materials | Aluminum, stainless, steel, brass, copper, titanium, plastics |
| Finishes | Anodizing, plating, black oxide, bead blasting, laser marking |
| Batch size | From one prototype to 10,000+ part runs |
| Inspection | 100% before shipment, reports on request |
Why GreatLight
Numbers behind the drilling work
±0.005 mm
Hole position tolerance
Held on critical patterns and checked with a CMM or pin gauges at final inspection.
127
CNC machines
16 simultaneous 5-axis centers, 12 four-axis mills, 27 three-axis machines and 16 mill-turn centers.
12 h
Quote and DFM
Drawing review, hole-by-hole DFM notes and pricing returned within 12 hours.
24 h
Production start
Material and tooling confirmed, machining can begin the next working day.
99.99%
Qualification rate
Raw material check, in-process monitoring and final inspection before any part ships.
4,000 mm
Maximum part length
Long rails and plates drilled on machines with a 4,000 × 400 × 150 mm travel.
3Wholly-owned plants
7,600 m²Manufacturing space
150Technicians on staff
ISO 9001 / IATF 16949Quality systems in place
Applications
What these industries require
Aerospace brackets
Thin ribs around close-tolerance holes, with breakout burrs controlled on both faces.
- ±0.005 mm
- 100% inspection
EV and automotive housings
Repeatable hole patterns across production runs, with IATF 16949 process control.
- IATF 16949
- 10,000+ part runs
Medical instrument bodies
Small-diameter holes and cross-ports with clean internal passages and documented inspection.
- ISO 13485
- Ø0.5 mm and up
Hydraulic manifolds
Deep intersecting bores drilled straight enough to keep flow paths aligned.
- 30:1 L/D
- Deburred passages
FAQs
Questions engineers ask before ordering
What hole sizes and depths can you hold?
We drill from Ø0.5 mm to Ø80 mm. For depths beyond 20× diameter we move to a gundrill on a vertical deep-hole machine, which keeps the bore straight enough for hydraulic and manifold work.
Anything past about 5× diameter should use through-coolant, so tell us the depth in the drawing rather than a note in the email.
How do you stop the drill from walking on an angled face?
We spot-drill with a point angle matched to the following tool, or mill a small flat where a spot drill cannot bite. On compound angles the part is positioned on a 5-axis machine so the entry is normal to the surface.
If the geometry still leaves a weak entry, we will say so in the DFM note and suggest a change, such as moving the hole off the slope or adding a boss.
Can you drill and tap in the same setup?
Yes. Drilling, counterboring and tapping normally run in one setup on the same machine. That removes a re-clamp and keeps the tap concentric with the drilled hole.
For thin-wall parts we often thread-mill instead of tapping, because the cutting force is lower and the wall does not distort.
What tolerance do you quote on hole position?
±0.005 mm is achievable on critical hole patterns, and we inspect those with a CMM or pin gauges. General holes are often fine at ±0.05 mm, and holding everything to the tighter number only adds cost.
Send the functional requirement, not a blanket tolerance, and we will tell you which holes actually need the tight callout.
Do you charge for a minimum order?
No minimum order quantity. A single prototype and a 10,000-piece run both go through the same process, though unit cost drops as batch size grows.
For a one-off, the setup and programming time dominate the price. That is normal for drilling work.
How are burrs handled?
We chamfer hole entries and control the breakout side, then deburr manually or by tumbling depending on the part. Internal passages get checked so no chip or burr blocks a flow path.
If the drawing calls for a specific edge break, such as 0.2 mm × 45°, tell us and we will hold it.
What do you need to quote a drilling job?
A STEP or DXF file plus material, quantity and any critical tolerances. A PDF with the hole callouts helps us flag issues faster.
We return pricing and a DFM note within 12 hours. If something is not manufacturable as drawn, we say so before the quote, not after the first part.
How do you protect our drawings?
Uploads are kept secure and confidential, and we sign an NDA on request. We do not share customer files or use them as marketing examples.
Ask for the agreement before you send the file if that is easier for your process.
Send your drawing, get a drilling quote
Upload a STEP file and we will return pricing plus a DFM note within 12 hours. No minimum order quantity, and every part is inspected before it ships.
12-hour quote100% inspectionNo MOQNDA on request
