Custom Drill Bushings
Manufacturer & Supplier
Accuracy starts at the bushing. We engineer and manufacture custom drill bushings tailored to your specific fixture geometry and tolerance requirements.
- True position maintained under high-volume drilling cycles.
- Custom ID/OD concentricity for critical alignment stacks.
- Built strictly to your jig/fixture engineering drawings.
Retention & Configuration Types
Engineered solutions for press-fit, slip-fit, and renewable applications.
Press-Fit (P)
Permanent installation for high-accuracy jigs. Precision ground OD for interference fit assurance.
Slip-Fit Renewable (S)
Designed for use with liners. Allows quick bushing changes for different drill sizes or replacement.
Head Type (H)
Flanged design to resist axial thrust loads from drilling forces. Prevents push-through.
Master Liners (L)
Hardened steel liners installed permanently to protect the fixture plate and accept renewable bushings.
Wear Mechanisms & Lifecycle Verification
Drill bushing life is governed by abrasive wear from chips and adhesive wear from the drill land. Our engineering team validates hardness depths to ensure longevity.
Case Depth Validation
We verify effective case depth to prevent premature bell-mouthing and loss of accuracy.
Microstructure Analysis
Ensuring proper carbide distribution in tool steel variants for maximum abrasion resistance.
Fixture Accuracy Stack-Up Analysis
Identifying and mitigating error sources in the drilling process.
| Error Contributor | Impact Mechanism | Mitigation Strategy |
|---|---|---|
| Bushing ID Runout | Drill wanders from true center. | Precision grinding ID concentric to OD within 0.005mm. |
| Fixture Plate Hole Position | Bushing axis misaligned relative to part. | Use of jig boring/grinding for liner installation holes. |
| Drill Margin Clearance | Excessive clearance allows drill chatter. | Custom closer tolerance IDs (e.g., G6 vs H7) for rigid tools. |
| Thermal Expansion | Heavy drilling heats bushing, changing ID. | High-speed steel or carbide inserts for thermal stability. |
| Chip Packing | Chips trapped between bushing and part. | Optimized “chip clearance” gap design tailored to material. |
Manufacturing Specifications
| ID Tolerance Capability | Standard H7, Precision G6, or custom limits to ±0.002mm. |
|---|---|
| OD Tolerance | Ground for press-fit (p6, s6) or slip-fit (g6) per ISO/ANSI standards. |
| Concentricity | ID to OD concentricity held to 0.005mm TIR (Total Indicator Reading). |
| Material Hardness | RC 60-64 (Standard Bearing Steel), RC 78-80 (Carbide), or custom heat treat. |
| Surface Finish | ID honed to Ra 0.4µm or better; OD ground to Ra 0.8µm. |
| Chamfer Geometry | Entry/Exit chamfers designed for easy drill entry and burr reduction. |
| Marking | Laser etched with Part Number and Drill Size (Inch/Metric). |
| Inspection Method | Air gauging for ID, Laser Micrometer for OD, Surface Profilometer. |
Inspection & Gauging Standards
Quality assurance for drill bushings is critical to fixture performance. We employ rigorous metrology to validate every dimension specified on your custom drawings.
- GO/NO-GO Gauging: 100% verification of ID limits.
- CMM Validation: Verifying true position of head features and special geometries.
- Surface Roughness: Stylus profilometry to ensure ID finish meets Ra specs.
- Calibration: All gauges traceable to national standards.
Replacement Strategy & Maintenance
Maximizing uptime with planned bushing service intervals.
Quick-Change vs. Fixed
Use slip-fit renewable bushings for high-wear applications to allow changeover in seconds without removing the fixture from the machine.
Service Intervals
Establish cycle-count based replacement. Typical intervals range from 5,000 to 50,000 holes depending on drill material and bushing hardness.
Signs of Damage
Monitor for “egg-shaped” holes, chipped exit edges, or drill chatter marks. These indicate the bushing ID has exceeded tolerance limits.
DFM: Optimizing for Custom Manufacture
Designing custom bushings effectively requires attention to installation and usage details.
Lead-in Chamfers
Ensure OD chamfers are specified to assist in press-fit installation without shearing the fixture plate hole.
Press-Fit Relief
For long bushings, specify a central relief (undercut) on the OD to reduce press forces and prevent distortion.
Anti-Rotation Features
For high-torque applications, add flats, dogs, or pin slots to the head to mechanically lock rotation.
Documentation & Traceability
FAI Reports
First Article Inspection per AS9102 available.
Inspection Data
Full dimensional reports with shipment.
Heat Lot Traceability
Material certs traceable to mill heat.
Process Control
Heat treat and plating certifications.
Industries Served
Aerospace Tooling
Automotive Fixtures
Medical Devices
General Manufacturing
Ready to Upgrade Your Fixture Accuracy?
Send us your part drawings or fixture layout for a comprehensive quote on custom drill bushings.
Frequently Asked Questions
What is the difference between press-fit and slip-fit bushings?
Press-fit bushings are permanently installed directly into the jig plate with an interference fit. Slip-fit bushings (renewable) fit into a liner and can be removed or replaced easily, secured by a lock screw or clamp.
What ID tolerances can you hold?
We can hold ID tolerances as tight as ±0.002mm (0.0001″) for high-precision applications, though standard H7 or G6 tolerances are common for general drilling.
Can you manufacture carbide drill bushings?
Yes, we manufacture solid carbide and carbide-insert bushings for high-volume production environments where tool steel would wear too quickly.
What happens if the bushing wears out?
Worn bushings cause drill wander and oversized holes in your parts. We recommend establishing a replacement schedule based on cycle counts to maintain fixture accuracy.
Do you offer quick-change options?
Yes, our slip-fit renewable bushings are designed for quick changeovers. We can also design custom locking mechanisms for specific fixture constraints.
What is the typical lead time for custom bushings?
Standard custom bushings typically ship in 2-3 weeks. Expedited services are available for urgent tooling breakdowns.
Is there a Minimum Order Quantity (MOQ)?
We specialize in low-volume custom manufacturing. While we can make single pieces, unit pricing improves significantly with batches of 10 or more.
What file formats do you accept for quotes?
We accept STEP, IGES, Parasolid, and PDF engineering drawings. PDF with tolerances is required for final manufacturing.
How do you verify the bushing ID?
We use calibrated air gauges and GO/NO-GO plug gauges to verify ID size and roundness across the entire length of the bushing.
Can you apply coatings?
Yes, we can apply TiN, TiCN, or DLC coatings to extend wear life or reduce friction for specific drilling applications.
Contact Us
Submit your inquiry below. Please attach drawings if available for a faster quote.
Our Location
Rongli Industrial Park, Dalang
Longhua District, Shenzhen, China