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Why Do Rivet Nuts Spin? Causes and Solutions

Editor：Wholesale Industrial Metal Nuts Manufacturer - F.I.T Fasteners │ Release Time：2026-10-19　
Rivet nuts create threaded connections in thin sheet materials and are widely used in sheet metal, automotive components, machinery, and other structures. However, a rivet nut may spin with the bolt during tightening, making it difficult or impossible to secure the connection. This is commonly known as rivet nut spinning or spinning out.

The problem can have several causes. Installation hole size, sheet thickness, riveting conditions, and rivet nut design can all affect its resistance to rotation.

Common Causes of Rivet Nut Spinning

1. Oversized or Incorrect Installation Hole

A rivet nut relies on its fit with the installation hole and its anti-rotation features to stay in place. If the hole is too large, the mechanical locking effect between the rivet nut and the hole wall is reduced. For knurled or hexagonal rivet nuts, an incorrect hole shape or a deformed hole can also allow the rivet nut to rotate with the bolt.

Solution: Measure the actual hole diameter and check the hole shape and wall condition against the product requirements. If the hole is significantly oversized, do not simply install the same rivet nut again.

2. Insufficient Riveting Deformation

During installation, the rivet nut must form sufficient deformation on the back side of the sheet to clamp the material. Incorrect tool stroke, installation force, or tool alignment can prevent the rivet nut from forming properly.

Solution: Check the installation tool, mandrel, and relevant settings. Make sure the tool is correctly aligned with the workpiece. For production runs, perform trial installations with the actual material before full-scale assembly.

3. Sheet Thickness Does Not Match the Grip Range

Every rivet nut has a specified grip range. If the actual thickness of a single sheet or a stack of materials falls outside this range, the back-side deformation may not develop as intended, reducing the holding and anti-rotation performance.

Solution: Measure the actual sheet or stack thickness and select a rivet nut with a suitable grip range. Thread size alone should not determine the product selection.

4. Rivet Nut Design Does Not Match the Base Material

Different rivet nut designs provide different levels and methods of anti-rotation performance. When used with thin or relatively soft sheet materials, an unsuitable design may not provide sufficient mechanical locking and can result in spinning.

Solution: Select the rivet nut design according to the base material, material thickness, and connection requirements. Where higher anti-rotation performance is needed, knurled or hexagonal designs may be considered, provided that the installation hole meets the product requirements.

Tips for Proper Rivet Nut Installation

1. Check the Installation Hole

Confirm that the hole diameter, shape, and wall condition meet the specified requirements. Remove burrs or obvious deformation that could interfere with proper rivet nut positioning.

2. Select the Rivet Nut Based on Sheet Thickness

Measure the actual thickness of the single sheet or material stack, then check the required grip range. Avoid selecting a rivet nut based only on the thread size.

3. Keep the Installation Tool Aligned

Keep the tool and rivet nut properly aligned during installation and avoid excessive tilting or off-axis loading. The tool condition and installation settings should also meet the product requirements.

4. Check the Formed Rivet Nut After Installation

After installation, check that the flange sits properly against the sheet and that the internal thread is not visibly damaged. For connections requiring strong anti-rotation performance, also verify that the rivet nut does not rotate during normal bolt tightening.

How to Check Whether a Rivet Nut Is Securely Installed

A properly installed rivet nut should be checked for flange contact, thread condition, and resistance to rotation. If the rivet nut starts turning during normal assembly, stop the operation and investigate the installation condition.

For production applications, first-piece inspection and process sampling can help verify installation quality. The specific inspection method should be determined according to the rivet nut type, base material, and manufacturer requirements.

Key insight

Rivet nut spinning does not necessarily indicate a product defect. Installation hole dimensions, grip range, forming condition, and rivet nut design should all be checked before changing the product. Identifying the actual cause allows the installation process or product specification to be adjusted accordingly.