A6196-8Z-1D - Aerospace Tinnerman Nut

A6196-8Z-1D – Aerospace Tinnerman Nut (Offset Anchor Nut)

Part Number: A6196-8Z-1D

Manufacturer: ARaymond Tinnerman (distributed via Textron/Boeing)

Standard Compliance: NAS445 Series (A191 Style)

Common Synonyms: Offset Lug Nutplate, Speed Nut, Sheet Spring Nut

Overview Section

The A6196-8Z-1D is a specialized aerospace-grade Tinnerman anchor nut, designed for securing thin-gauge panels where traditional riveted nutplates or heavy machine nuts are impractical. Unlike "U" or "J" type Tinnerman nuts that clip over the edge of a panel, the A6196 series is an Anchor Type (nutplate style) that is riveted or screwed permanently to the structure, providing a captive, vibration-resistant mounting point for removable panels.

The "8Z" designation indicates compatibility with a #8 sheet metal screw (typically Type B), while the "1D" suffix signifies a high-performance Zinc Metallic Olive Spray finish. This finish provides superior corrosion resistance for exterior airframe components, protecting the high-carbon spring steel from environmental degradation.

Enhanced Technical Data

Advanced Engineering & Structural Application

The A6196-8Z-1D is engineered for Vibration Resistance and Weight Savings. In non-structural aerospace assemblies, the use of spring-steel nuts allows for a degree of "float," which compensates for minor hole misalignment during assembly.

Engineering Insight: The Thread-Locking Principle

Tinnerman nuts derive their locking power from two distinct forces:

1. Arched Prong Lock: As the screw is tightened, two arched prongs are forced against the root of the screw thread, creating a constant frictional lock.

2. Spring Tension: The base of the nut is arched; as it is compressed against the panel, it exerts an upward force on the screw threads, preventing loosening due to the high-frequency vibrations found in engine cowlings and wing tips.

Offset Configuration

The "Offset" design of the A6196 means the mounting lugs are not symmetrical. This is specifically utilized in tight corners or narrow flanges where a standard two-lug nutplate (like the A6191) would interfere with an adjacent vertical wall or another fastener.

Aircraft Compatibility

The A6196-8Z-1D is an essential airframe fastener for various Textron and legacy platforms:

• Beechcraft Bonanza / Baron / King Air: Extensively used in wing-tip fairings, landing gear doors, and internal inspection panels.

• Cessna Piston Series: Found in engine baffles and localized interior trim attachments.

• Hawker 400XP / 800XP: Utilized in non-pressurized fairings and environmental system access panels.

The Textron Aviation A6196-8Z-1D is the industry standard for lightweight, secure panel fastening. When maintaining your airframe’s exterior fairings or interior panels, utilizing the correct Tinnerman hardware is critical for preventing panel "chatter" and fastener loss. This offset anchor nut provides a permanent, captive thread solution that is significantly lighter than standard all-metal nutplates while offering the vibration resistance of high-grade spring steel. Finished in a protective olive-drab zinc coating, the A6196-8Z-1D ensures long-term reliability in corrosive environments.6

Installation & Maintenance Addendum

1. Screw Compatibility Warning: These nuts are designed specifically for Type B sheet metal screws (blunt tip).7 Never use machine screws (8-32) or pointed Type A screws, as the thread pitch and root diameter are incompatible and will destroy the nut's locking prongs.

2. Rivet Selection: Use 3/32" solid rivets (AN426 or AN470 depending on panel flushness) to secure the lugs to the structure. Ensure the mounting holes in the A6196-8Z-1D are correctly aligned with the panel hole to allow for the nut's natural "float."

3. Replacement Policy: If the prongs of the A6196-8Z-1D become flattened or "stripped" due to over-torquing, the entire nut should be replaced. A Tinnerman nut that does not provide physical resistance when the screw is inserted has lost its self-locking capability.