To Protect and Solidify the Manufacturer’s Warranty

This is a practice often used for electronics – tamper proof fasteners that keep customers out of the guts of the system, yet allow the manufacturers full access. If a product is brought back for warranty, the condition of the fasteners on the outside casing will notify the service department whether anything has been tampered with inside. If so, the warranty is likely void. If not, it will stand.

This protects the public and the business. It is standard practice for many manufacturers today. Tamper proof screws tend to add little to the initial cost and protect the manufacturer from unnecessary service costs, helping to maintain affordability and competitiveness in any marketplace.

Security and Permanence

Many times the signage and structures installed at building sites get damaged or vandalized. And valuable electronic equipment is often left in unsupervised locations that leave the equipment vulnerable to theft and damage. There are other instances where fixtures, doors, windows and other items need to be secured well.

Correctional facilities use tamper proof fasteners to prevent any alterations and damage. Contractors use these products to ensure both temporary and permanent structures are better protected. Technical and computer manufacturers use these screws, nuts and washers to maintain a high level of security in racks and systems. Whatever the incidence or application, tamper proof products provide a high level of security and increase confidence and safety.

To Maintain Industry Secrets and Limit Access

This is a common practice in electronics, where competitors can easily adapt the new and emerging technologies. In order to maintain industry secrets and limit access to the design and features of electronic devices, many manufacturers design or use their own unique fasteners. This ensures that the inside of the devices are less vulnerable to casual review, although determination and the right tools will usually work to loosen any tamper resistant and tamper proof products.

By no means a foolproof method of protecting their R&D, manufacturers and designers know that tamper proof fasteners are only one stage in the fight to keep advances in technology under wraps.

Shear Nuts

This specially designed nut works with any bolt of a comparable size. It has a standard hex head on one end that is attached to a smooth, conical shaped extension. When the nut is tightened that hex head actually shears off, leaving the conical shape on the bolt. This component acts as a stable nut, but is exceptionally difficult to remove.

Your application will have all of the stability and strength needed with the conical nut, but these fasteners do not present an easy removal method.

Torx Screws

One of the most popular lines of security screws, Torx is the brand that is often used for tamper proof applications. These fasteners have a specially formed recess that cannot be tightened or loosened using a standard bit. If one of these bits are used it will be obvious that the screw was tampered with. If your application requires tamper resistance, rather than a serious deterrent against tampering, these screws are a good option.

There are many different types of tamper resistant fasteners that come in a wide variety of designs and sizes. Many times a manufacturer will use a specific style (or two) of tamper resistant screw, if only to streamline the bits required for assembly. If they also need to provide a bit to their customers for at home assembly, it makes sense to use the same style of screw in various locations.

Oddly Shaped Nuts and Screws

One of the easiest ways to produce a tamper proof or tamper resistant fastener is by making the shape unique. Sometimes it is the nut that is oddly sized and unable to be tightened by regular means; other times it is the screw head that includes a strangely shaped recess. Both of these designs work very well.

They can easily be maneuvered with the right tool, but otherwise these fasteners will need to stay put. This set up provides an acceptable level of security for many different applications.

No matter what option is used, tamper proof fasteners add value to your project and can be utilized to protect your customer and your business.

When you apply force to fasteners (commonly referred to as torque) it will inevitably put stress on the fastener in some way. Often the material or coating will stretch, strain or become compressed. When the incorrect amount of torque is used it can (and often does) result in fastener failure.

So how can you avoid this situation?

In order to avoid dangerous situations, many engineering specifications will state the torque required. Maintenance and assembly workers need to pay attention to these specifications and use only the amount of torque stated by the designers or manufacturers.

It is important to note that most often an acceptable torque range will be stated. That means you can use any torque value within those limitations and still be assured of stability. These figures are calculated by taking the type of fastener into account, as well as the size, grade and thread of the product.

Coatings and lubrication are also important factors. The torque values should state whether any lubrication can be used and applications that deviate from this will require another calculation. Different coatings also change the accepted torque – so don’t expect to use the same force on an untreated bolt as you would on a galvanized product.

Always keep in mind that the torque applied to the fasteners will also have an effect on the fitting. You need to be sure that the torque used will not result in damage to the fitting materials. Splitting, cracking and weakening are all common results of too much torque. Plastics and other soft materials are often at risk of these conditions.

Anyone dealing with fasteners on a regular basis should use a top quality torque wrench to ensure accuracy. These tools allow for the application of exact levels of torque and will help to avoid fastener failure and fitting damage in many cases.

Not really.

Standard Nails Vs Deck Screws

For wood decks (pressure treated and cedar) it depends on whether or not you choose to screw or nail the decking down. Most of the framing will be built using 3 1/4″ hot dipped galvanized nails, with joist hangers and lag bolts taking their place as well. For the deck boards and railing, either ceramic coated or stainless steel deck screws can be used.

Composite Deck Fasteners

When composite and vinyl decking is used you will also need to invest in specialty deck screws. These products are designed to produce a smooth, problem-free surface that eliminates mushrooming (that build up of shavings that occurs when standard shaped screws are used with the softer composite and vinyl products) and splitting.

If a fastener line is marketed for use with composite decks it will also be available in different colors. The head of these screws are coated to match the most popular tones of composite – including grey, sand, red and dark brown. Buy enough of your preferred color to complete the entire deck, as each lot of screws may be a slightly different shade.

Mismatched Materials

You need to be aware that certain materials are not to be used together – such as ACQ lumber and deck fasteners not approved for use with this treatment. The chemicals in ACQ treated lumber will eat away at many common fasteners, causing structural damage and presenting a serious danger to all who use the deck. Be sure to ask your supplier about any limitations and follow all of the directions carefully, resulting in a safe and secure structure for your family to enjoy.

Almost any design will require similar deck fasteners for the framing. The deck boards and railing is where you may need to invest in a specialty product and make sure the screws or nails you have chosen are suitable for the project. Ask the pros and don’t hesitate to spend the money on high quality deck fasteners to be sure your outdoor living space is built to last.

Tek Screw Dimensions and Threads

Teks are distinct in design, as they are chosen not only for the screw length, but also for the drill bit diameter. Look for drill point numbers similar to those stated on commercial drills – ranging from 000 (the smallest and measuring around 0.0600″ in diameter) up to number 12 (0.2160″ in diameter) and beyond. You will find tek screw drill bit points in common fractional sizes such as 1/2″, 5/8″ and 3/4″. Remember that the diameter of the drill bit point is always smaller than the actual diameter of the fastener. Tek screws come in common diameters, including number 8 (0.1640″), 10 (0.1900″) and 12 (0.2160″).

In terms of thread density, or the count of threads found per inch of screw length, most tek brands have between 12 and 14 threads per inch. This is similar to standard screws.

Different Heads Available

You’ll find tek screws in all of the common head types. For light or common carpentry tasks, flat head teks are available, while Phillips and Robertson (or square) heads are used in many other applications.

You can find this type of screw in countersunk style, allowing for a flush surface finish on your application. There are also styles with an integrated neoprene washer that provides protection and a seal on the metal surface.

Magnetic tek screws use rare earth magnets inside the screw head to allow for precise, hands free installation. This type is in high demand for tight spots and in applications where small screws need to be fitted into dark corners or otherwise inaccessible places.

Consider the needs of your application in order to purchase the right style of tek screws. These fasteners make quick, efficient work when attaching metal to metal or metal to wood, but having the proper screw is still important.

The answer depends on your application and the condition of the materials being fastened.

In many situations you can apply torque to either the nut or the bolt head. Both will result in a tight connection and neither will avoid breakage more often (that occurrence can be avoided through other means). In certain circumstances, however, you will need to torque one and not the other. These situations include:

Holes Are Producing an Interference – If the holes you are bolting through (whether existing or drilled for the purpose) provide an interference, you are better to apply torque to the nut.

Nut and Bolt Head are Different Diameters or Shapes – When the nut or bolt head are different shapes (hex head with a square nut, for instance) or significantly different diameters, you are best to apply torque to the side with the smaller bearing face. This also applies when the hole diameters are different. It is generally recommended that you apply torque to the component opposite the smaller hole.

When Clamping Two Different Materials Together – It is always better to apply torque on the component that is against the material with a lower frictional coefficient. If you are clamping together different materials and you know which one will produce less friction, it is best to torque that side.

Long Bolts Are Being Used – When torque is applied to the head of a very long bolt, you may see the effects of torsional wind-up. Applying torque to the nut in this situation will help to avoid that issue.

There will be many instances where you can apply torque to either the nut or the bolt head. But if one of the above situations applies, remember to follow the guidelines for a better fit and more durable installation.

Flat Head and Trim Heads

These are what most people think of when they are asked to pick up deck screws. A flat head is common to both and they can both be countersunk into the wood or composite material. Alternatively, both flat head and trim head screws can be inserted into a predrilled hole and covered with a plug to ensure an ultra smooth finish. Generally a trim head screw is chosen when a surface mount is required, though.

Pan Head and Washer Heads

These are the opposite of flat head screws, in that they are designed to sit on top of the surface. For that reason they are most often seen on heavy plastics and metal applications where countersinking is not an option. But the main benefit of both the pan head and the washer head screws is that the shape of the head allows for better distribution of the load. You can use a washer head screw just like you would a screw and washer combo, except you don’t have the hassle of handling two fasteners.

Other Types of Screws

You may also come across oval head screws. Similar to a round head screw that has been flattened, this type of screw is used to provide a snag free surface that is relatively smooth. Nautical applications put the oval head screw to good use.

Truss head screws offer a very large head that provides more surface area to distribute the load. Often used with a nut on oversized holes, this type of screw is sometimes called a bolt as well.

Excellent Service

A local fasteners distributor has a leg up on the distributor from a foreign location. Not only do local firms know your working conditions, they are also familiar with the business climate and all of the ins and outs of running a company in your neck of the woods.

Are there certain state or provincial tax implications that are applicable to your business or project? Dealing with a local will eliminate the need to explain those in detail or waste time filling out paperwork to set up the business transactions properly.

Does your building or electrical code specify a particular fastener material or design due to climate or other issues? The fastener distributor that is established in your neighborhood will be familiar with those codes and will even help you to comply better with advice and suggestions.

Speed is of the Essence

A major factor to deal with when buying from a foreign distributor is the speed of delivery. Getting the fasteners you need from an overseas firm will take time. And even if you find those items for a cheaper price, getting them shipped to your location will take time and money. Are you willing (and able) to wait?

Not only will the speed of delivery make a difference, but the rapid service in terms of quoting and putting through orders will also be a plus. A local distributor will have similar hours of operation (being in the same time zones has its privileges) and when telephone service just won’t do, visiting local firms is possible.

Personal service by a local rep is likely to be more dependable from a nearby company or even one that is in your state (as opposed to those in another country). And that kind of service is what will help make your project smooth and successful.

The key is to understand which materials are best in which situations.

Potential Problems

Obviously the thermostat swings both ways. There may be instances or prolonged exposure to extremely high heat (such as in an engine) or your design may call for resistance and strength in very low temperatures (such as exterior applications in a northern environment). Each circumstance could potentially cause the fastener to weaken or seize, as well as affect the plating and coating.

Heat can bring on oxidation and both extremes present the danger of corrosion. Basically, your fasteners need to able to handle the temperature or they will break down and fail.

High Heat

Most nonferrous (or those that do not contain iron) fasteners should be avoided in high temperatures. Plastics are out. Choose medium carbon (Grade 5 fasteners, for example) or low alloy steel for hot temperatures up to 450 degrees. But if your application is pushing above that range you will need to opt for a stronger material and possibly even move into heat treatments.

For conditions ranging between 450 and 900 degrees stainless steel is a great option. You’ll also be handling corrosion resistance with this option, although steel containing chromium-molybdenum can also be used.

From 900 degrees on there are super alloys that are specially developed for resistance and stamina. Inco 718 and A-286 are recommended up to 1200 degrees and fasteners made from nickel-cobalt alloys can withstand heat to 1600 degrees.

Heat Treatments

Ferritic steel (which covers steel that is mainly made up of ferrite and contains some chromium) are heat treated for strength in extreme temperatures. The process is somewhat different for each grade of steel, but generally the material is cooled to a low temperature, reheated to refine the grain and then quenched in liquid or normalized in air before being reheated for tempering.

There is a stated minimum temperature for the tempering process that ranges from 1100 degrees to 1200 degrees Fahrenheit, depending on the grade. Also, certain grades stamped with B6 and B6X are held at the tempering temperature (not that’s a tongue twister) for at least one hour. If the material is stress-relieved after tempering tests are necessary.

Stainless steel is treated in a slightly different way. The material is cooled then reheated, held there until the chromium carbide forms a solution and then cooled (in air or liquid). This process will result in a Class 1, 1B or 1C fastener. When a 1A class is needed the material will also be treated with a solution once the heating and cooling processes are done.

Extreme Cool

In certain circumstances your fastener may be exposed to prolonged cold. In consistent temperatures below minus 30 degrees there will be problems with toughness and ductility and the metal can become brittle. This means that materials that are notch sensitive shouldn’t be used in extreme cold, materials like low carbon steel (Grade 2 fasteners, for example).

Nickel-rich grades like AISI 4340 and 8740 can be used if the temperature stays above – 100 degrees Fahrenheit. For frigid conditions between -100 and -300 degrees Fahrenheit stainless steel is your best bet. Non-metallics have a chance to shine in cold temperatures, especially Teflon. Also alloys like Unitemp 212, Inco 718, Waspalloy and A-286 stand up to extreme cold. Interestingly enough, these same alloys also stand up to extremely high heat (up to 1200 degrees), creating a high demand in these unique circumstances.

Temperatures affect different fasteners in different ways. With some basic knowledge you can make a good choice, something that will stand up to whatever the surrounding climate throws at it. Research steams ahead at full power thanks to space exploration, where extreme temperatures take on a whole new level. But those of us still down here on earth are grateful for the information and data that helps us to make strong, dependable choices.