Breakstem Fasteners: A Complete Guide
In short: Breakstem fasteners are installed from one side by pulling a stem until it breaks off, leaving a permanent joint. The range runs from general-purpose multi-grip rivets to high-strength structural fasteners.
See: Light Engineering, ToolingTalk to our technical team
Breakstem fasteners are blind fasteners: they are installed from one side of the joint. A stem (mandrel) runs through the fastener body. The installation tool pulls the stem, which expands the body on the blind side and clamps the parts together, then the stem breaks off at a set load.
Why breakstem fasteners are used
- One-sided access: ideal for hollow sections, panels and closed assemblies.
- Speed: fast to install with hand, pneumatic or battery tools.
- Consistent quality: the stem breaks at a controlled load, so every joint is made the same way.
- Versatility: types for almost every material and load.
Avlock’s Breakstem® range
- Multi-grip rivets: general-purpose, covering a wide range of thicknesses.
- Sealed rivets: watertight and airtight joints.
- Peel rivets: for soft and brittle materials.
- Colour rivets: coloured to match panels.
- Plastic rivets: for light, non-conductive joints.
- Bulbex®: for thin sheet and oversized holes.
- KTR rivets.
- Structural fasteners: Monobolt®, Hemlok®, Maxlok®, Avtainer®, Avbolt® and Avdelok® for high-strength, vibration-resistant joints.
Where to start
For background, see Rivets Explained and How to Choose the Right Rivet. For specialist types, see Sealed, Peel and Bulbex® Rivets and Structural Breakstem Fasteners.
The full range is on the Light Engineering page, with the tools to install it. Avlock manufactures breakstem rivets at its Boksburg factories.