Physical Address
304 North Cardinal St.
Dorchester Center, MA 02124
Surface Discontinuities on General Application Bolts, Screws, and Studs: SAE J1061 and Its Replacement
SAE J1061 is a recommended practice that defined acceptable surface discontinuities for general application bolts, screws, and studs. Published by SAE International and first issued in 1973, it provided manufacturers and engineers with criteria for evaluating surface irregularities such as cracks, seams, laps, slivers, and folds. The standard was cancelled in November 2012 and superseded by ASTM F788/F788M.
Background and Scope
The standard applied to general application fasteners, meaning those not subject to specialized requirements like aerospace or critical safety systems. It covered metric and inch-series bolts, screws, and studs, defining limits based on fastener size, grade, and location of the discontinuity.
Acceptance Criteria for Surface Discontinuities
| Discontinuity Type | Description | Typical Acceptance Criteria (per SAE J1061) |
|---|---|---|
| Cracks | Fractures in the material | Not permitted on bearing faces or thread roots beyond a certain depth |
| Seams | Material folds from rolling | Allowed if within length/depth limits per fastener size |
| Laps | Folded metal from forging | Acceptable if confined to non-critical zones |
| Slivers | Narrow strips of material | Permitted if not compromising fit or strength |
| Folds | Overlapping metal | Controlled by dimensional limits |
| Voids | Cavities due to material defects | Typically prohibited in load-bearing areas |
Transition to ASTM F788/F788M
In 2012, the SAE Fasteners Committee reviewed both SAE J1061 and ASTM F788/F788M and determined there was enough similarity. Consequently, SAE J1061 was cancelled and superseded by ASTM F788/F788M. Engineers and specifiers should now reference the ASTM document for acceptance criteria for surface discontinuities on general application bolts, screws, and studs.
⚠️ Important: SAE J1061 is no longer active. Always reference ASTM F788/F788M for new designs and procurement.
🛠️ Design Insight: Surface discontinuities can affect fatigue life, assembly, and corrosion resistance. For critical applications, consider additional inspection methods such as magnetic particle or liquid penetrant testing to verify compliance with ASTM limits.
Frequently Asked Questions
Q: What types of surface discontinuities are covered by SAE J1061?
A: The standard addressed cracks, seams, laps, slivers, folds, and other surface imperfections common to manufacturing processes for bolted fasteners.
Q: Why was SAE J1061 cancelled?
A: Because ASTM F788/F788M provides equivalent coverage. SAE retired the standard to avoid duplication. Both documents are similar in scope and requirements.
Q: How should I specify fastener surface quality now?
A: Reference ASTM F788/F788M in your procurement documents, along with the fastener grade and size. For critical applications, you may also require third-party inspection.
Q: What are the main differences between SAE J1061 and ASTM F788/F788M?
A: The two documents are very similar. SAE J1061 was a recommended practice while ASTM F788/F788M is a specification. ASTM may contain more detailed inspection requirements and acceptance limits. Engineers are advised to consult ASTM for exact criteria.
