The term “TEK Screw” has gained a trademark. TEK screws are self-tapping and self-drilling, which means they have a drill tip with a very small carving piece, so no pre-drilling is required. HVAC ductwork, solar panels, electricity, and metal roofing screws are popular for metal-to-metal applications.
The value of screws has been redefined thanks to TEK screws. They appear ordinary; however, they are pretty helpful on the job site. The shank lengths and diameters of TEK screws are available in various sizes. The numeric size of diameter ranges from #6 to #14, with #6 being the thinnest and #14 being the thickest.
The most popular TEK screws are #8 and #10 TEK screws. However, there is more to these self-drilling screws. In our guide, you can learn more about the TEK screw capacities and other additional information.
By the end, you can confer with our self-drilling screw sizes chart to ensure you have the correct size fasteners for any roofing applications you may do, or sometimes wood when you need to ultimate wood to metal fixings. (Read Drywall Screw Sizes Chart)
What Do TEK Screw Numbers Mean?
TEK screws are a piece of essential equipment at any job site. They’re suitable for a wide range of applications and can help you save time when drilling screws.
TEK screws are not all created equal. Instead, a number distinguishes them, such as #4 and #5.
Self-drilling screws, generally known as TEK screws, are self-tapping screws in the same way sheet metal screws are. It differs because it features a drill-shaped point that can cut through the material without a pilot hole.
TEK screws are made of hard metals like stainless steel and can drill through soft steel or metals having a harder drill point than the metal being drilled into.
Drill bit tips on self-drilling screws are numbered from #1 to #5, denoting the flute length. The flute is the component of the TEK screw that regulates how thick of metal the screw can drill through.
The higher the number, the thicker the metal through which it can pass without a pilot hole. TEK 4 and TEK 5 screws have the following capacities:
- TEK 4: The #4 point can drill through steel with a thickness of 0.25 inches (6.35 millimeters).
- TEK 5: The #5 point can drill into steel up to 0.5 inch (12.7 millimeters) thick.
TEK 5 and TEK 4 screws are ideal for a variety of metal-to-metal and wood-to-metal, to complete projects in one operation, including:
- Electrical Industry
- Studs made of steel
- Outside and inside
TEK screws will give a secure grip for these applications. Air conditioning systems and canopies, for example, are suitable candidates for these thread forming screws since they can be taken apart for repair or rebuilding frequently. (Read Wood Screw Sizes Chart)
What Size Is A TEK 5 Screw?
Features of TEK 5 Steel-to-Steel Self-Tapping Screws
Drill Point TEKs
- Cutting edges, non-walking
- Faster material engagement, less effort drilling, and a safer installation
Drill Point & Tapping Threads Integrated
- Drilling to tapping transition is made quickly.
- Reduce the installation torque.
A variety of head types are available.
- HWH, Oval, Pan, PPH, PSD, HWH, Oval, Pan, PPH, PSD
A wide variety of finish options are offered.
- Climaseal, Climacoat, Electro-Zinc, and Gray Spex (All Trademarks)
Standard self-drilling TEK screws were never designed to move from metal to wood. As a result, the hole created by the drill bit will be near the same diameter as the external threads of the threaded portion of the fastener, thus preventing the threads from tapping into the wood and securing the fastener.
Some self-drilling screws designed for roofing applications are an exception to this rule.
The drill bit used on those screws is a #1 drill bit, and the diameter of the hole created by the drill bit is significantly smaller than the diameter of the screw’s external threads.
The threads can bite into the material, and the screws can self-tap into the metal or wood for a strong hold. For fastening metal to metal and sometimes wood to metal, contractors use TEK screws.
Depending on the thickness of the material you’re drilling through, you can choose from various drill points, the longest of which is the TEK 5, sometimes known as a beam buster, as it is designed exclusively for wood use.
These screws allow the user to join two pieces of material with no pre-drilling and get a secure hold.
TEK screws are self-drilling screws in various shank sizes, lengths, and head designs.
Depending on the type of work you’re doing, you’ll need a different type to finish your project.
The hex washer heads, and modified truss head are two of the most prevalent head styles on TEK screws on the market. When a flush surface is required, flathead screws are used. Most contractors who work on heavy-duty metal installations favor the hex drive.
|Screw Size||Screw Threads per Inch||Recommended Hole Diameter||Drill Bit Size|
Initially used in sheet metal ventilation ducts, tapping screws, especially Type A, are known as “sheet metal screws.” But more types emerged.
Types of Self-Tapper Screws
Spaced threads are shown by a screw bearing the letter “B” in its identification (Type AB or B). If the “B” is missing, the screw is machine screw threaded (Type F). Two exceptions: Type A has spaced threads and is outdated. Type U metallic drive screws have spaced spiral threads.
Besides self-drilling screws, including sharp point types, hole size is critical for all other tapping screws.
If the screw is loose, the hole may strip, or the screw may pull out under tension. A small hole requires more driving effort, which can break the screw or cause the material to crack or split. So always drill or punch the exact size hole.
For usage in thin gauge malleable materials, thread forming screws require a hole of the correct size. Installing the fastener simply enlarges the hole by pushing the material outward.
So, burrs are common. Type A and AB, both with a standard point, and Type B, with a blunt point, are common sheet metal screws. Sizes vary from #2 to 3/8.
If the metal is thicker and tougher, thread-cutting screws are used. The flutes on these screws work as a tap to create mated threads in the material when they are installed. A hole of the right size is required. Chips, like taps, are created.
For blind holes, ensure sure the depth is adequate. If the screw is inserted through a hole, the chips exit the hole. Prevent metal chips from causing electrical shorts, contaminating lubricants, or impeding mechanical function. (Read Nutsert Drill Size Chart)
Type F thread cutting screw is quite popular. The threads of machine screws are closer than sheet metal screws. A machine screw of the same size can replace a thread cutting screw that tapped a hole (diameter and number of threads per inch). 4-40 to 1/2-16 are common.
Self-drilling screws, commonly known as TEKs®, feature a drill-like tip and spaced threads like sheet metal screws. These screws drill, tap, and fasten in a single step, saving time. Use self-drilling screws sparingly (holes that do not pass through the material).
Also, the drill point must drill entirely through the material before the first thread may thread into it. So, the threads are thoroughly engaged with the material. Drill chips impact electrical devices.
There are four-point styles: #2, #3, #4, and #5. A #2 point is used for light gauge materials, a #3 for medium gauge, and a #4 or #5 for heavy gauge materials.
Type U metallic drive screws have spiral threads and a blunt point. The screws are pressed into the material. Drive screws are permanent, whereas tapping screws are removable.
Plastic, particleboard, Masonite, and wood are all low-density materials that benefit from High-Low threads. The high thread is quite sharp, whereas the common thread is more typical and half the height of the high thread.
Installing these screws is more manageable, and thread stripping is minimized while pull-out strength increases.
How Long Is A #10 TEK Screw?
The following materials are available for self-tapping fasteners:
Zinc-Plated Steel is the most prevalent and has excellent rust resistance when screwing metal.
Weather-Guard Coated improves the protection of ferrous metals against rust and corrosion over many standard coatings.
Stainless steel is available in 18-8 and 410 grades. The corrosion resistance of 18-8 is excellent.
A unique hybrid combining a strong steel driver fused at the mid-body with an 18-8 head provides exceptional drilling and corrosion resistance.
Head and Other Styles of TEK Screws
- Hex Washer Head –The built-in washer provides a superior bearing surface. They come slotted or unslotted, with the latter being the most common. The length is measured from the base of the neck to the top of the head.
- Pan Head – A Phillips or square drive head with a low profile. The length is measured from the base of the neck to the top of the head.
- Flat Head — This countersunk head dips into the wood for a flush finish. The length is measured from the top of the head.
- Oval Head — A countersunk base with an oval on top delivers a polished look, similar to a flat head. The height of the head is used to determine the length.
- Flat Head Reamer – A flat-top and Phillips drive ream wood and then cut steel in one action with a flat head reamer. Wings ream clearing holes in thick layers of low-density materials to prevent thread engagement. The wings fall off, and the threads usually engage when the point penetrates the metal beneath. The height of the head is used to determine the length.
- Round Washer Head — These have a round head with a Phillips drive, similar to HWH. They are also known as either Metal Lath or K-Lath and modified.
- Truss Screws – Truss Screws are measured from the underside of the head.
- Wafer Head – A Wafer Head is also known as ply metal because it may join plywood and metal. The big wafer head has a broad bearing surface and digs into the plywood. The height of the head is used to determine the length.
- Drywall Bugle Head – Drywall Bugle Heads are used to secure drywall to metal studs (0.105′′). The height of the head is used to determine the length.
- Pan Framing – A Phillips drive stud-framing screw used to fasten a stud to a track. The length is measured from the base of the neck to the top of the head.
- Pancake Head – A head with a low profile and a big bearing surface. The length is measured from the base of the neck to the top of the head.
- Square Trim–This model has a square drive and a smaller head for confined places. The length is measured from the base of the neck to the top of the head.
Special Purpose Fasteners
|To 2 Sheets of 24 Ga.|
|Ply metal TEKs||No. 10||To .175 Max.|
|Ply metal TEKs|
|No. 10||.089 Min. To .175 Max.|
|Drywall TEKs||No. 6|
|Up To 26 Ga.|
|Gypsum TEKs||No. 6||.035 To .090|
|.089 Min. To .210 Max.|
How To Use TEK Machine Screw Threads
You can drive TEK thread forming screws with a drill or an electric screwdriver. In addition, you can drill a pilot hole to ensure that the screw will go in straight.
When drilling a pilot hole, make sure it’s slightly smaller than the TEK screw.
The screw’s grooves will not catch and ensure secure fastening if the hole is the same size or greater.
One advantage of self-drilling TEK screws is that they do not require a pilot hole, which is why many individuals choose not to do so.
If you don’t use a pilot hole, take your time driving the TEK screw in straight. Tighten it firmly but not excessively once it’s in place. Over-tightening might cause head stripping, making future removal of the TEK screw difficult.
You should make sure that the metal thickness of the object you’re drilling into is thinner than the drill point length on your TEK screw, regardless of whether you use a pilot hole.
If the screw’s threads contact the metal’s surface before the tip has bored through, the screw will snap because the tip and head will move at different speeds, causing stress in the middle.
Self-drilling stainless steel screws are available, but the tips aren’t ideal for drilling stainless steel. (Learn How To Use Dishwasher With Broken Soap Dispenser)
For this purpose, bi-metal TEK screws are recommended, which have a stainless body but a carbon steel tip that permits the screw to drill into the stainless.