How to Choose the Correct Rivet
The right rivet starts with the joint it needs to secure. The materials, combined thickness, loading and operating environment all influence your choice. This guide covers the key points to check when selecting a blind rivet.
1. Match the Materials
Choose a rivet body and mandrel combination compatible with the materials being joined. Aluminium, steel and stainless steel options offer different strength and corrosion characteristics, while copper is used in some specialist applications.
Consider the complete material combination, particularly where dissimilar metals will be exposed to moisture. A corrosion-resistant rivet is not automatically compatible with every panel material.
2. Check the Grip Range
The grip range is the minimum and maximum combined material thickness a rivet is designed to fasten. Measure the assembled thickness and choose a rivet whose published grip range includes it.
For example, a 2 mm sheet joined to a 3 mm sheet gives a combined thickness of 5 mm. The selected rivet must be suitable for that thickness, including any other layers retained within the joint.
Do not choose by overall rivet length alone. A rivet outside its grip range may not form correctly or secure the assembly as intended.
3. Select the Diameter and Hole Size
Common nominal diameters include 3.2 mm, 4.0 mm, 4.8 mm and 6.4 mm. Select the diameter using the required joint performance and the rivet's published data, rather than assuming a larger rivet will always provide a better connection.
Prepare the hole to the manufacturer's specified diameter and tolerance. Hole quality, edge distance and panel strength also affect the finished joint.
4. Choose the Head Style
- Dome head: A common option for general-purpose joints where a projecting head is acceptable.
- Large flange head: Offers a wider bearing surface on the accessible side, which can be useful with thin or softer materials. Check that the blind-side formation is also suitable for the panel.
- Countersunk head: Provides a flush finish when fitted into a correctly prepared countersink. Confirm that the panel is thick enough for the required preparation.
5. Assess the Joint Loads
Two important published values are shear strength, which relates to forces acting across the rivet, and tensile strength, which relates to forces pulling the joint apart.
These figures do not describe every possible failure mode. Panel bearing, edge tear-out and head pull-through can also limit performance. Account for the number and spacing of rivets, vibration and repeated loading when assessing the complete joint.
For demanding or structural applications, select a rivet specifically designed and rated for the task, supported by an appropriate joint design.
6. Consider the Environment and Sealing
Check exposure to moisture, chemicals and temperature, together with any coating or appearance requirements. Stainless steel or coated rivets may be appropriate in some environments, but the grade and compatibility still matter.
A sealed blind rivet can help control leakage through the rivet body. It does not automatically make the whole joint watertight: the head-to-panel interface and surrounding assembly may also need sealing and testing.
7. Confirm Tool Compatibility
Use an installation tool and nosepiece suitable for the rivet type, diameter and material. The tool must provide the required pulling force and stroke to set the rivet correctly.
Check trial installations before production, particularly when working with unfamiliar materials or a new rivet design.
Before You Order
Have the panel materials, combined thickness, required loads, head style, environment and available installation tool details ready. These give a much better starting point than rivet diameter alone.
Need Help Choosing?
Contact Rivetnut Technology Systems to discuss your application. Share the joint details and any performance or sealing requirements so the rivet and installation method can be considered together.