What Does It Mean When Bolts Shear Off?
If you’re building a fence, chances are you’re going to need nuts and bolts and other kinds of fence hardware.
No matter what kind of fence system you’re creating, it’s the nuts and bolts that hold everything together. However, sometimes, bolts fail, and in some cases, that happens through a process called shearing. Here’s what you need to know about why bolts shear and how you can prevent this from happening to your fence.
What Does It Mean When You Say Bolts Have Sheared?
The term shearing, when it comes to bolts, basically means that the bolt has snapped off, usually on the shaft or threaded portion of the bolt.
Since the bolt cannot keep your fence together if it’s broken in half, this means that the bolt has failed. Either it will have to be replaced, or your fence will lose its structural integrity.
Why Do Fence Bolts Shear?
The most common reason that fence bolts shear is because they have been subjected to a sudden force. Often, in the fence world, this means that the bolt was not tightened enough, and one of the components it was holding moved, striking the bolt with enough force to cause it to break.
Any bolt can shear if it’s subjected to enough force at the right angle, but this is more common with thinner bolts, and it happens more commonly with lower-quality bolts and fittings.
Can You Fix a Bolt That Has Sheared?
While you might be tempted to fix a bolt that has sheared on your fence, it’s usually best not to. Welding bolts will never give you a good result, and there’s always a chance that the bolt sheared because there was a weakness in the bolt that might not have been visible.
How to Prevent Fence Bolts Shearing
In a perfect world, we wouldn’t ever have to deal with sheared fence bolts because they would all be strong enough to take the weight of the fence for the duration of its lifespan. However, we don’t live in a perfect world!
There are some things you can do to try to prevent bolt shearing on your fence, though:
- Choose the best quality bolts and fence hardware possible
- Make sure your bolts are of sufficient diameter to support the components it’s fastening
- Ensure that all bolts are properly tightened – any vertical or lateral movement of fence components could lead to shearing
Don’t Dismiss Shear Off Nuts!
While we’ve spoken about the downsides of fence bolt shearing so far, there is one type of shearing that you might want on your fence!
Shear-off nuts, also called shear nuts or breakaway nuts, are a special type of security nut that has a hex head that’s designed to snap off when tightened. This leaves a much more secure, smooth cone of steel behind, making the fence that much harder to tamper with.
When In Doubt, Defer to Engineers
As with anything related to the design of a fence system, it’s always best to defer to the manufacturer’s design team and the project engineers. It is possible to calculate what size your bolts need to be to prevent shearing and keep your fence strong and in good shape, but it’s usually not something that fence companies do on their own.
Whatever you do, though, a little good design, proper installation and quality materials go a long way to prevent fence-related problems!
