CR3214-4-02 - Cherry Aerospace CherryMAX 100 Degree Flush Head Blind Rivet

CR3214-4-02 – Cherry Aerospace CherryMAX® 100° Flush Head Blind Rivet

Available now on the Airparts.aero Marketplace.

The Cherry Aerospace CR3214-4-02 is a high-strength, structural blind rivet engineered for demanding aerospace applications where access is limited to one side of the structure. This fastener is distinguished by its Monel sleeve and alloy steel stem, a material combination selected for superior shear strength and enhanced corrosion resistance, particularly in challenging environmental conditions. Its 100° countersunk head design allows for a perfectly flush installation on aircraft skins and aerodynamic surfaces, maintaining surface smoothness critical for performance.

As part of the venerable CherryMAX® family, the CR3214-4-02 utilizes a patented, mechanically locked, flush-fracturing stem system. During installation, the high-strength steel stem is drawn, forming a large blind-side head, filling the hole, and clamping the sheets together. Before the stem fractures, a locking collar is swaged into a groove, creating a permanent mechanical lock that guarantees stem retention. This retained high-strength stem enables the rivet to carry significant shear loads, comparable to solid rivets in many applications. The stem consistently breaks flush with the rivet head, eliminating secondary shaving operations and streamlining the installation process.

Key Features

• Genuine CherryMAX® Rivet: The industry benchmark for reliable, high-strength structural blind fastening.

• Monel Sleeve: Offers superior strength and excellent corrosion resistance compared to aluminum sleeves, suitable for demanding environments.

• Alloy Steel Stem: Provides exceptionally high shear strength, making this rivet ideal for shear-critical joints.

• Positive Mechanical Stem Lock: Features a swaged locking collar that ensures the high-strength stem is permanently retained, guaranteeing structural integrity.

• Flush-Fracturing Stem: Engineered to break flush with the rivet head consistently, eliminating the need for post-installation trimming or shaving.

• 100° Flush Head: Allows for a perfectly flush installation in countersunk holes, essential for external aircraft surfaces.

• Excellent Hole-Filling Capability: Radially expands during installation to completely fill the prepared hole, creating a tight, vibration-resistant joint.

Technical Specifications

• Part Number: CR3214-4-02

• Component Type: Structural Blind Rivet

• Manufacturer: Cherry Aerospace

• Governing Specification: Qualified to National Aerospace Standards such as NASM90353 M (Supersedes NAS1400M).

• Materials:

  • Sleeve: Monel Alloy (Nickel-Copper Alloy)

  • Stem: Alloy Steel

  • Locking Collar: Monel

• Head Style: 100° Flush Head (Countersunk)

• Diameter: -4 (1/8 inch / 0.125 inch nominal)

• Grip Range: -02 (0.063 - 0.125 inches)

Aircraft Compatibility

The CR3214-4-02 is a standard structural fastener used in the manufacturing and repair of a wide range of aircraft from major OEMs, including Textron, Boeing, Airbus, Lockheed Martin, Bombardier, Gulfstream, and others, particularly where high shear strength and corrosion resistance are required in a blind application.

Crucial Note: The correct rivet part number, including diameter, material combination, and grip length, for a specific repair must be determined from the applicable aircraft Structural Repair Manual (SRM) or an approved engineering disposition. Material compatibility with surrounding structures (galvanic corrosion) must be considered.

Applications

The CR3214-4-02 is designed for permanent, high-shear structural joints where access is limited to one side and a flush finish is required. Common applications include:

• Aircraft Skin Repairs and Panel Attachments

• Joining Ribs, Stringers, and Spar Components

• Engine Nacelle and Pylon Structures

• Areas requiring higher strength than aluminum rivets.

• Applications where enhanced corrosion resistance is needed.

Why Choose CR3214-4-02?

Choosing a genuine CherryMAX® CR3214-4-02 is a critical decision for structural integrity, especially in high-load or corrosive environments. This rivet's Monel sleeve and steel stem provide significantly higher shear strength than typical aluminum blind rivets. The mechanically locked, retained stem guarantees this performance, unlike simple break-stem rivets. Furthermore, the flush-breaking stem offers significant labor savings over older systems requiring shaving. For demanding structural repairs in blind applications requiring a flush finish, the CherryMAX® CR3214 series is the certified, high-strength solution.

The installation sequence of the CherryMAX® CR3214-4-02 leverages controlled material deformation and mechanical locking to achieve superior joint strength. The pulling action of the installation tool's jaws on the alloy steel stem performs several functions nearly simultaneously: it draws the stem head through the Monel sleeve, causing the sleeve to radially expand and fill the hole (hole-fill); it continues to pull the stem head, forming a large, upset head on the blind side which clamps the sheets together (sheet clamp-up); and finally, as maximum clamp load is achieved, the tool's anvil swages the Monel locking collar into the stem's lock groove (stem lock). Only after the collar is fully formed and mechanically locked does the stem fracture at its engineered break notch, flush with the sleeve head. The high shear strength of the joint is derived primarily from the retained alloy steel stem, while the cold-worked Monel sleeve provides excellent corrosion resistance and contributes to bearing strength. Careful consideration of galvanic compatibility is required when using Monel rivets in aluminum structures.

Note: This is a flight-critical structural fastener. The selection of the correct grip length is essential for proper blind-side head formation and stem locking. Hole preparation, including diameter, perpendicularity, and countersink depth/angle, must be performed in strict accordance with the maintenance manual. This rivet must be installed using a specific CherryMAX® pulling head (e.g., H90353 series) and a properly calibrated riveting tool. Installation must be performed by a certified A&P mechanic or airframe technician.

Documentation

• Cherry Aerospace CherryMAX® Product Page (General Information)

• The definitive technical requirements and installation procedures are detailed in the Cherry Aerospace product documentation and the applicable National Aerospace Standards (e.g., NASM90353 M).