IFI Drill Point Die Specifications: Complete Size Reference
Complete IFI (Industrial Fasteners Institute) drill point die specification reference. Size chart from #4 to #14, drill diameters, point lengths, and die series mapping for self-drilling screw production.
IFI Standards for Self-Drilling Screws
IFI references and the specified SAE or other product requirements help define the finished screw. ZLD catalog codes describe production tooling and do not themselves constitute IFI certification.
Use the exact customer-approved standard edition and drawing alongside the catalog size reference. Approximate metric equivalents do not establish interchangeable products.
IFI Size Chart with Die Specifications
Complete Cross-Reference Table
| IFI Size | Nominal Ø (mm) | Metric Equivalent | Drill Ø Range (mm) | ZLD Die Series |
|---|---|---|---|---|
| #4 | 2.84 | ~ST 2.9 | 2.2–2.4 | L1–L2 |
| #6 | 3.50 | ~ST 3.5 | 2.7–2.9 | L1–L3 |
| #7 | 3.81 | ~ST 3.9 | 3.0–3.2 | L1–L3 |
| #8 | 4.17 | ~ST 4.2 | 3.3–3.6 | L1–L4 |
| #10 | 4.83 | ~ST 4.8 | 3.7–4.2 | L1–L5 |
| #12 | 5.49 | ~ST 5.5 | 4.3–5.1 | L1–L7 |
| #14 | 6.35 | ~ST 6.3 | 5.3–5.7 | L1–L7 |
Detailed Die Code Mapping
| IFI Size | Available Drill Diameters (mm) | Die Codes |
|---|---|---|
| #4 | 2.2, 2.3, 2.4 | L1-22, L1-23, L1-24 |
| #6 | 2.7, 2.8, 2.9 | L1-27, L1-28, L1-29 |
| #7 | 3.0, 3.1, 3.2 | L1-30, L1-31, L1-32 |
| #8 | 3.3, 3.4, 3.5, 3.6 | L1-33, L1-34, L1-35, L1-36 |
| #10 | 3.7, 3.8, 3.9, 4.0, 4.1, 4.2 | L1-37, L1-38, L1-39, L1-40, L1-41, L1-42 |
| #12 | 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9, 5.0, 5.1 | L1-43, L1-44, L1-45, L1-46, L1-47, L1-48, L1-49, L1-50, L1-51 |
| #14 | 5.3, 5.4, 5.5, 5.6, 5.7 | L1-53, L1-54, L1-55, L1-56, L1-57 |
How to Select the Right Drill Diameter
Drill diameter must be compatible with thread geometry, material, thickness, coating and the required joint strength. Increasing diameter simply because the plate is thicker can reduce thread engagement; validate the chosen hole/point geometry by the specified screw test.
Selection Principles
- Establish the thread form, approved point geometry and finished drilling test.
- Check substrate grade, full stack thickness and installation conditions separately from the production wire.
- Match the catalog Dø and code to the drawing, then validate the complete fastener after its required heat treatment and finish.
Validate the Diameter for the Assembly
For #10 / approximately ST4.8, the catalog Dø range is 3.7–4.2 mm. It offers several geometries, not a rule that thicker plate requires a larger diameter.
Compare the hole produced by the finished screw with the intended thread engagement and joint test. Record substrate grade, thickness, coating and installation conditions. Choose the approved geometry and then its catalog code; do not increase Dø solely from plate thickness.
Point Length Standards
Point-number systems used by fastener suppliers must be interpreted using that supplier’s drawing and rated capacity. They are not direct equivalents of ZLD L-series numbers.
Check actual flute length, thread-free zone and clearance needed for the complete material stack. Confirm whether the point clears before the threads engage, then test the fastener under its rated conditions. Point number alone neither establishes structural suitability nor requires carbide tooling.
Testing per IFI Standards
Drill Performance Test (per SAE J78)
Use the applicable SAE J78 edition or the specified alternative to establish the test plate, material condition, thickness, spindle speed, axial load and acceptance criteria. Record the equipment and observed drilling time for traceability.
Run the complete fastener in its required heat-treated and finished state. Assess drilling and thread formation, plus any specified torsional requirement. Repeat comparisons under the same conditions; a point that looks correct may still fail its functional test.
Dimensional Inspection
Define critical dimensions and measurement methods from the approved drawing.
| Feature | Useful inspection approach |
|---|---|
| Dø and point width | Optical measurement or a suitable calibrated gauge |
| Point position | Datum-based optical or fixture measurement |
| Flute profile and symmetry | Profile inspection against the drawing |
| Edge and surface condition | Agreed visual or magnified inspection with measurable criteria |
Verify the measurement system can resolve the agreed tolerances, and record whether inspection occurs before or after finishing.
Common Die Ordering Mistakes
Mistake 1: Ordering by Screw Size Only
"I need dies for #10 screws" is insufficient. You need to specify:
- Drill diameter (3.7mm? 3.9mm? 4.1mm?)
- Point type (#1, #2, #3?)
- Material (tungsten carbide or HSS?)
Mistake 2: Using Same Die for Different Materials
Changing an installation substrate may require a different finished-screw geometry, but the die itself contacts the production wire. Confirm both the point drawing and the wire/process before reusing tooling.
Mistake 3: Ignoring Plating Thickness
Specify the coating system and actual thickness allowance in the drawing. The buildup and distribution depend on the process and point geometry; a fixed per-side zinc allowance is not universal.
Measure critical point dimensions before and after the required finish, and test the finished screw. Include any drawing allowance in the tooling design.
Ordering Guide
When ordering drill point dies to IFI specifications, provide:
- IFI screw size (#4 through #14)
- Target drill diameter (in 0.1mm increments)
- Point type (#1 through #5)
- Die material (tungsten carbide / HSS)
- Production volume (helps determine die grade recommendation)
- Provide the pointing-machine model and die-pocket dimensions; a header model alone may not identify the pointing station.
Get IFI-Compliant Dies
ZLD Precision Mold manufactures drill point dies for the complete IFI size range (#4–#14). Our specification table maps every IFI size to available die codes and drill diameters.
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