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Installing Break Away Shear Nuts

Security Nuts That Shear Under TorqueBreak away nuts

Break away shear nuts are security nuts that break or shear under a certain pressure. These nuts are designed to be installed and never removed. You will often see them on street signs or in other places where vandalism may occur. These nuts are designed to have a structural flaw in them to create a breaking point.

Installation

The first step in installing these nuts is to hand tighten them onto a bolt. Once you get them snug against the installation material you will need to start tightening them with ashear nuts wrench. Hold the bolt in place with a wrench and then grip the nut end from the other side with another wrench. Spin the wrench onto the nut side and as the nut tightens against the material (use a washer if the material is soft to avoid damage) it will begin to place force on the flaw.

Once the flawed area of the nut reaches its breaking point, half of the nut, the side with the hexagonal gripping area will break off, leaving only a coned end behind.

The end result is a secure fastener assembly that will be incredibly difficult to remove. The cone shape makes gripping devices such as vice-grips effectively useless at removal. The hexagonal end is considered a throw-away part and cannot be reused. Shear nuts are similar to tri-groove nuts in shape, however they do not have the grooves built in that are needed for removal.

shear nut after install

Please Remember that these nuts are very difficult to remove. Make sure you only use them where you never intend on removing them again.

 

installed shear nut

How to Install and Remove a Carriage Bolt

Carriage Bolt Install and Removal

The Setup

The first thing we need to do when installing a carriage bolt is to make sure we have the right parts and tools to do so. For this job we will need a:

For our example, we have already pre-drilled the hole into a piece of 2×4 and attached it to a vice. This will act as our installation surface for our carriage bolt.

Understanding A Carriage Bolt

carriage bolt setup

A carriage bolt is a bolt with threading all the way up the shank to a small square shoulder, with a domed head. The square shoulder of a carriage bolt stops it from spinning as it is screwed into the surface of a material. You would not typically use this type of bolt on very hard wood as it may not properly dig into the material, which would cause the bolt to spin in place. Once you seat the bolt through the hole, it is the job of the nut and washer to pull the bolt into the material tightly. Since there is no drive device for the domed head of the bolt, this is the only way to install it.

The Install

The installation process is fairly simple. First, you drill a hole into the wood for the appropriate size (diameter) of the bolt. Next you slide the bolt into the hole (you may need a hammer as the hole should be just big enough for the bolt to go through).

drill the hole

Now that you have the nut through the wood it is time to attach the nut and  the washer. Place the washer on the rear side of the bolt followed by the nut. The washer will help to distribute the force you are about to put onto the nut to pull the bolt into the wood. This will not only protect the wood on the back side but also keep the bolt from digging into it and getting stuck.

tighten nut with washer

As you tighten the nut, the square shoulder on the bolt will be pulled into the wood. Once the underside of the head rests against the wood, the carriage bolt is officially installed.

The Removal

Removing the carriage bolt is a fairly simple process. First, you will want to twist the nut close to the end of the bolt. DO NOT TAKE THE NUT ALL THE WAY OFF THE BOLT, you will need it to help move the bolt along.

prepare to remove and loose nut

Once the nut is backed off to the end of the bolt, hit the nut with a hammer. The force  should start moving the square shoulder out of the wood. As you move the  bolt further out the nut will get closer to the wood. When this happens continue to back out the nut and strike it again. Repeat this process until the bolt is loose enough to take out by hand or the nut can no longer grip the bolt.

push out bolt with hammer

If you find the bolt is stuck but the nut can no longer attach to the bolt, use the nail remover attached to the hammer and use it to pry the bolt out of the hole.

removing process is complete

It’s That Simple

There you go now you know everything you’ll need to know about installing and  removing carriage bolts. As always, Albany County Fasteners stresses the need for protective gear while working with dangerous materials. Remember to ALWAYS wear safety glasses while drilling to protect your eyes and wear protective gloves that fit to keep your hands safe from harm as well.

Full Installation and Removal process you can find on our Youtube channel

Installing Tapcon Masonry Screws

How To Install Masonry Screwsinstalling masonry screws

Masonry screws are used to fasten materials to different masonry materials (usually concrete). Tapcon is a brand that has become a generic term for these screws over the years, often referred to as tapcon screws.

Tapcon screws can be identified by their blue coloration. Most of them are fully threaded but some longer screws will have a smooth shoulder. This shoulder is designed to disperse the heat built up by the screw. If the shoulder was absent the screw would heat up exponentially and expand it the hole. This expansion plus the heat of the screw can compromise its integrity causing the screw to snap.

Now that we know a bit about masonry screw lets begin installing one.



Getting Started

What you will need:

  • Concrete Drill Bit
  • Drill
  • Painters Tape
  • Tapcon Screws
  • Various Driver Bits depending on which head style you choose
  • Safety Gear!installing tapcon screws

Step 1

The first thing we need to do is take the screw we are going to install and mark the end of the drill bit with painters tape. We do not want to drill an excessive hole in the concrete it only needs to be long enough.

Once we have our drill taped, its time for the most important part of our drilling into concreteinstallation. Putting on our safety gloves and glasses to make sure we protect ourselves.

Step 2

With our safety gear on and drill in gloved hand we can begin drilling our hole into the concrete. Even short concrete screws will hold very well in concrete. These masonry screws cut their own threads and will only need to be installed a little over an inch to have some true holding power. Once you reach the desired depth marked by the tape, you may remove the drill and carefully wipe any extra debris away from the hole.

Step 3

screwing in tapcon masonry screws

This is the home stretch for installing a concrete screw. Find the appropriate bit driver. We decided to use the hex head slotted Tapcon screws due to their popularity. Simply drill the screw into the hole until the head reaches the surface of the concrete and you are done!

 

finished tapcon screw install

 

Using Keps K Lock Nuts – Quick Tip

Installing Keps K Lock Nuts

Keps K lock nuts are nuts that have a free spinning serrated washer attached to them. These nuts are made to create tension against the material when installed onto a bolt. It is important to NEVER over torque these nuts. Once you over tighten a lock nut it loses its functionality.

Keps K Lock Washer

The picture below is a hand tightened keps k nut with no added torque. You can see the teeth are pressing lightly against the metal material we have installed the bolt through.

Keps K nut install

Once we have tightened the bolt very lightly you can see the teeth have extended out to create tension against the object. If you over-tighten this type of lock nut you will ultimately flatten out the teeth and when you remove the nut you will see that the teeth no longer perform any function they will just act like a washer.

Installing a Keps K lock nut

Keps K locks are ideal for applications where you might use an external tooth lock washer and nut but the combination is more convenient. You need to carry around fewer parts making installation much faster. They also save you from the fumbling of little lock washers that seem to be designed to fall from your hands and disappear.

Tri-Groove Security Nuts

“Trident” Tri Groove Security Nuts

Tri Groove security nuts are nuts that are installed with a very unconventional drive. These nuts have three slots in them, making them unique in shape and appearance. They have a cone shape, designed to be gripped only by the device intended to tighten and loosen them.

You can commonly find these in places where security or vandalism is a concern. To test these nuts we decided to install one ourselves and test a couple of different tools to see if we could remove them quickly.

tri groove nut install

First, we installed the nut using a tri-groove socket tool specially designed for this drive style. After install, we attempted to tamper with this fastener ourselves to determine what it would take to remove it.

how to break tri groove nut

We tried using an adjustable wrench. That didn’t work, the cone shape of the nut showed no gripping areas to lock the wrench into. We also tried pliers which had the same effect. Vice grips were our last attempt to break this nut loose with a conventional tool. However, the cone shape made it incredibly difficult to find a locking point. So we attempted to grab the lip and the base of the installation. The lip proved to be too small to get a good grip, leading us to our conclusion.

attempt to break tri groove nut with wrench tool
attempt to break tri groove nut with tool

Conclusion

Having tested several different removal methods for removing this nut, we have determined that without either the proper tool or physically altering the shape of the nut (perhaps with a grinder) to provide a gripping point for more conventional tools, it is unlikely that this nut will be easily tampered with when installed correctly.

*Although these nuts are fairly secure there is still a chance that someone could have enough know-how or time to alter the shape of the nut or may have come across the proper tool to remove them.

Installing & Removing Tri-Groove Tamper Proof Security Nuts | Fasteners 101 See Full Video in Our Youtube Channel.