.125"- .750" Thick
Production Time
“I had to do some post processing to get countersunk holes that I needed… parts were clean and accurate. Saved me a lot of time.”
Our countersinking service is compatible with four aluminums and three plastics. Materials must be at least 0.125″ thick.
Countersinking adds 1-2 days to production. For the fastest lead time, order countersunk parts separately
4.1 x 4 in
Laser cutting, countersinking
6 x 4 in
Laser cutting, countersinking
5.4 x 6 in
Laser cutting, bending, deburring, countersinking, anodizing
Draw only the minor hole in your CAD file
Do not include the major diameter; the countersink is machined to the correct size automatically.
Holes under 4″ are automatically resized
You are responsible for ensuring adequate edge clearance and spacing between features after resize.
Countersink direction matters
Countersinks can be applied from the top or bottom face. Use the 3D preview in the app to verify orientation before ordering.
| Major diameter | Should match fastener head diameter (~50% larger than minor hole). Do not include in your file |
| Minor diameter | Defined by your CAD file, must match intended fastener size |
| Max countersink depth | Should not exceed 60% of material thickness |
| Countersink angle: 82° | Standard for imperial/SAE hardware |
| Countersink angle: 90° | Standard for metric hardware |
| Contact requirement | Aim for ≥ 50% contact between hardware and countersink |
| Accuracy | ±0.015″ |
| Standard Flat Head Bolt | Major | Minor | Depth |
|---|---|---|---|
| 4-40 | 0.255” (6.48mm) | 0.130” (3.18mm) | .072″ (1.83mm) |
| 6-32 | 0.307” (7.80mm) | 0.164” (4.04mm) | .082″ (2.08mm) |
| 8-32 | 0.359” (9.12mm) | 0.193” (4.78mm) | .095″ (2.41mm) |
| 10-24 | 0.411” (10.44mm) | 0.199” (4.93mm) | .122″ (3.10mm) |
| 10-32 | 0.411” (10.44mm) | 0.199” (4.93mm) | .122″ (3.10mm) |
| 1/4-20 | 0.531” (13.49mm) | 0.255” (6.35mm) | .159″ (4.04mm) |
| 1/4-28 | 0.531” (13.49mm) | 0.255” (6.35mm) | .159″ (4.04mm) |
| 5/16-18 | 0.656” (16.66mm) | 0.318” (8.08mm) | .194″ (4.93mm) |
| 5/16-24 | 0.656” (16.66mm) | 0.318” (8.08mm) | .194″ (4.93mm) |
| Metric Flat Head Bolt | Major | Minor | Depth |
|---|---|---|---|
| M2 x 0.4mm | 4mm (0.157”) | 2.39mm (0.099”) | .074mm (.029″) |
| M2.5 x 0.45mm | 5mm (0.197”) | 2.49mm (0.103”) | 1.19mm (.047″) |
| M3 x 0.5mm | 6mm (0.236”) | 3.18mm (0.130”) | 1.35mm (.053″) |
| M4 x 0.7mm | 8mm (0.315”) | 4.04mm (0.164”) | 1.93mm (.076″) |
| M5 x 0.8mm | 10mm (0.394”) | 5.00mm (0.202”) | 2.44mm (.096″) |
| M6 x 1mm | 12mm (0.472”) | 6.35mm (0.255”) | 2.77mm (.109″) |
| M8 x 1.25mm | 16mm (0.630”) | 8.00mm (0.320”) | 3.94mm (.155″) |
More details are available from our preferred vendor, McMaster
Avoid placing countersinks too close to edges, other holes, or bend lines.
Deep countersinks require additional spacing between features and thicker material to maintain strength.
Multiple countersinks placed close together risk material deformation or part failure under load.
Surface condition: Parts may have oil or lubricant residue from the countersinking process. Light cleaning may be required.
Edge condition: Some sharp edges or burrs may remain after machining. Minor deburring may be needed.
Finish quality: Countersinks are functional features, not cosmetic. Tooling marks or light scoring may be visible.
Powder coating impact: Adds .002″–.005″ per side. Hole sizes are adjusted, but fit may still be tight on countersunk features.
If you’re designing parts for countersinking, these resources may help:
Top Quality Store
Please note: Pricing examples on our website are provided as general estimates and may not always reflect current prices. While we strive to keep these examples accurate, uploading your file is the best way to see instant current pricing.
We accept .ai, .dxf, .dwg, .eps, .stp, and .step
Customize one of our simple parts templates
