Guide to Woodworking Screws

ProMaster® Plus patented thread design features cutters built right into the thread design. Tiny saw blades are formed into the first three to four thread revolutions that cut through the wood while displacing a minimum amount of material. By displacing less material than a Type - 17 point, the ProMaster thread design offers greater holding power. Our testing shows that it offers 15 percent more holding power than a double Type -17 screw sold by our competitors while eliminating splitting. This new revolution in thread design technology was developed for and is very popular in the furniture and woodworking industry for its easy driving while offering optimum holding power.

Production Screws

The sharp threads help to prevent the wood from splitting, and the hardened steel shanks reduce breakage. Because the screw shank is straight throughout its entire length (except for the point), drilling a pilot with a straight drill bit yields excellent results. The reduced shank diameter at the head means an enlarged body hole isn't necessary. Finally, the straight bit doesn't require the critical depth control needed with a tapered bit.

Point types on Production Screws can vary. Please see the Section below focusing on Threads and Points.

Drywall Screws

Drywall screws lack the strength of production screws and are designed to hold drywall to studs. Coarse threads are designed and work best when attaching Drywall sheets to Wood Studs. Fine threads are best for attaching to metal studs. Some people promote using Drywall Screws in woodworking because they are cheaper and easy to drive. because of the threads. Drywall screws are hardened and lack any give when driving into wood, especially hardwood, and can snap while driving them in or, worse, fail under any kind of side load. The thinner shank This is why you should never use Drywall Screws for anything other than attaching Drywall to studs.

Pocket Hole Screws

Pocket-hole joinery is popular because it is a fast, strong, easily adaptable, precise assembly method. Joints are as strong as mortise-and-tenon joints and can be made in a fraction of the time. Award-winning Kreg Jigs® use a 3/5 in. counter-bore bit with an 11/64 in. pilot to drill and 15° angle into the first piece. With the joint tightly clamped, a special self-drilling pocket-hole screw is placed in the pocket and driven tight to complete the joint. Pocket-hole screws feature an auger point to prevent raising a chip between the two parts during assembly, ensuring a tight joint. A larger Fillister or Washer Head with a #2 Square recess and extended unthreaded shank enables the screw to draw the two members of the joint tight. The higher head profile provides a deep recess, making this head style easier to drive.

Deck Screws

ProMax® screws are optimized Thread Length to prevent Board Jacking. The screws normally used to install 2x4s or 2x6s for decking are 3 in. long and have 1 in. of unthreaded shank. Since 2x4 and 2x6 deck materials are 1-1/2 in. thick, the threads bridge the joint, resulting in either uneven and unsightly surfaces or screws that are over-driven trying to "pull the board down. ProMax screws are different. Thread length is optimized to eliminate cross-threading. Plus, the 1/8 in. L system allows the use of the longest possible screw.

Confirmat / Firmit Connecting Screws

MDF Board is an artificial material and presents a special challenge when fastening. The material is composed of 'wood dust in a resin matrix; no traditional grain structure can resist withdrawal forces. Your options are to make sure you are pre-drilling a pilot hole and use a little longer screw to gain the additional holding power. Your second option is to use your Confirmit or RTA screw. They have deep threads on an oversized shank, a clearance-hole diameter shoulder beneath the head, and a head that is just slightly larger than the shoulder. Installation requires a special three-step drill bit, resulting in a tight, strong joint.

Traditional Lag

Lag Bolts are just over-sized screws - way over-sized! That makes them perfect for tasks that are even too big for a #12 screw, especially exterior jobs. Unfortunately, lag bolts that could handle challenging environments have been almost impossible to find. You don't need to redesign your project to get around the lag bolt problem. These tough lag bolts are plenty strong (up to 30% more torque capacity than standard steel lag bolts), with all the corrosion resistance of 18-8 stainless steel.

Commonly found in Galvanized Coating and Stainless Steel for High Corrosion Areas. DO NOT mix Stainless Steel Screws on Galvanized Brackets, and the dissimilar metals will cause a Corrosion factor that will shorten the life and safety of the structure.

Modern Lag Screws

Modern Lag Screws offer a lower head profile (Washer Head) or the Traditional Hex/Hex Washer Head with sharper threads and narrow shank that require no pre-drilling and drive faster and easier than conventional lags and other structural screws. They come in a variety of coating for interior or exterior use.

Trim Head Screws

The small head size requires extra care with the driver bit.

Head styles on Trim Head Screws can vary by manufacture and also application. Trim Head screws for use in wood applications can look one way, and Composite material can look a different way.

Connector Screws

Joint Connector Bolt Wood screws (JCBW) are ideal when you need a strong right-angle joint with a decorative, low-profile head. They are commonly found on “ready-to-assemble” (RTA or KD) furniture. Roughly equivalent to a #14 wood screw, these screws have deep threads for exceptional holding power. Predrilling for these screws is a must: 3/16 in. for softwoods, 7/32 in. for hardwoods. The head is 17mm (approx. 11/16 in.) dia. x 2mm (5/64 in.) high and has a decorative beveled edge. Install using a 4mm hex driver. Plated, low-carbon steel.

Connector Bolts and Barrel Nuts

Connecting bolts and barrel nuts make strong joints. You’ve probably built some “ready-to-assemble” (RTA) furniture that used this fastener. This fastener is popular because it creates strong joints, doesn’t depend on the poor fastener-holding power of end grain, and is virtually impossible to assemble the joint incorrectly, a real advantage in the RTA market. Joint construction is easy. Drill a 1/4" clearance hole into the end grain for the connector bolt. Then, drill an intersecting 13/32"-dia. Hole for the 3/8"-dia. Barrel nut. Drop in the barrel nut, align it to the connector-bolt hole, slip in the connector bolt, then tighten with a 4mm Allen wrench, and you’re done. Critical details: The connector-bolt head is 15mm (a bit less than 5/8") in diameter and 3/32" thick. The holes in the barrel nuts are offset 1/4" from the bottom.

What About Those Point Sizes

Self-drilling/self-tapping screws must be matched to the thickness of the material they will fasten to work properly. Unlike fasteners selected by length and diameter, these screws are specified by point size. The self-drilling point must be through the material before the self-tapping begins, so the drill point must be longer than the combined thickness of the fastened materials. The screw will cross thread if the materials are separated when tapping begins and will cause thread stripping or drive stalling.

Maximum Material Thickness

• Zinc-Plated #8 Screws with #2 Point .035" to .100"
• Zinc-Plated #10 Screws with #3 Point .110" to .210"
• Stainless Steel #8 Screws with #2 Point .059" to .110"
• Stainless Steel #8 Screws with #3 Point .098" to .142"
• Stainless Steel #10 Screws with #3 Point .110" to .177"
• Stainless Steel #12 Screws with #3 Point .110" to .209'
• Stainless Steel #14 Screws with #3 Point .110" to .248"

Flat Head Wood Screws

The top of the head is flush with the material when the screw is seated. The countersink normally has an 80-82 degree angle. Variations of this angle are in use. Some European hardware requires a 90° or 100° head angle.

Flat Head with Nibs

There are usually four or six ridges protruding from the surface that cut into the material as the screw head penetrates the wood. This is designed to eliminate precountersinking the screw hole. NIBS work very well in soft and hardwoods, MDF, and laminates. They can also reduce splintering of the wood around the head of the screw.

Trim Head Wood Screw

Trim Heads are specially designed for applications in which the head of the screw needs to be as small as possible. Trim Heads resemble finish nails in both appearance and function. The head of a #4 screw is used on a #6 or #7 screw, permitting the screw to countersink itself just like a finish nail. The small head size allows it to be used to discreetly attach molding and trim to millwork, cabinetry, and crafts.

Bugle Head Screw

The bugle head design countersinks consistently and neatly, and the deep recess provides maximum driver bit fit. We added a self-drilling Type-17 point to alleviate splitting in most types of wood and man-made materials. Made from 1018-1022 steel, they are case hardened for maximum strength and feature rolled coarse threads to provide maximum holding power in a variety of materials.

Oval Head Wood Screws

The oval-head screw extends above the surface in a slight oval. Some consider this feature to give the screw more pleasing appearance. They are often used with exposed hinges. When used with metal parts the hole must be beveled to accept the countersink on the screw.

Round Head Wood Screws

It's mainly used as a Decorative Screw. Round-head screws are more limited use in building trades than are flat-heads. The flat bottom side gives the screw its holding power while the Round upper surface is decorative in nature. This screw is commonly used with machinery more than woodworking because of the protrusion of the head.

Round Washer Head

They can have either a pan or round head with a built-in washer extending beyond the circumference of the basic head diameter. The round washer head design could possibly be the most versatile head design available. It combines the advantages of the pan head but has a washer built onto it to increase head diameter and prevent overdriving in softwoods while providing a maximum bearing surface. They are often used in the furniture industry to attach wood drawer guides and tops to side panels. In cabinetry, they are popular for mounting wall and base cabinets.
An X-Tra Large or Super Round-Washer Head has become popular for attaching drawer fronts to the drawer box. The extra-large head allows an oversized hole to be drilled in the drawer box, and when the drawer front is rotated for alignment, the large washer covers the hole.

Pan Head Wood Screw

The flat surface under the head is called the bearing surface, and this head style is often used to attach metal or plastic hardware parts to wood. The higher head profile provides a deep recess, making this head style easier to drive. The flat bearing surface also reduces over-penetration when the head is used directly against wood surfaces.

Fillister Head Wood Screw

The higher head profile provides a deep recess that makes this head style easier to drive. These screws are known for their high strength, accuracy, quality, and durability. Mainly found in Pocket-Hole Screws, the Head is usually undersized by one size to prevent the head from scraping the walls of the Pockethole. This could cause the screw to not go in straight and create a weak joint.

The difference is that the countersink under the head does not extend down to the shank at an angle. This is used on the thinner gauge drawer slides so the screw will seat better in the slide. The countersink in the drawer slide can vary based on material thickness. We have an undercut head screw that works well on all slides. We undercut the flat head so the screws drive tightly against the slide and does not interfere with the mechanism.

Truss Head Wood Screw

Because the head profile is lower, the recess is shallower and sometimes is more difficult for a worker to keep the drive tool engaged in the recess. Some drawer slides require a lower head height so the screw head will not interfere with the passage of the slide roller. The lower head is also less obtrusive when seen in the finished product. Most 8-32 machine screws used for attaching drawer knobs and pulls have a truss head design.

Modified Truss Head Screw

Sometimes called “K-Lath” screws, Modified Truss Head Screws are used for attaching metal lath to steel studs; corrugated siding panels to steel studs and other applications requiring attachment to steel studs.

Wafer Head Cabinet Wood Screw

The wafer-head screw is great for general wood-to-wood fastening where a low-profile head is needed. Wafer Head screws commonly feature a flat top surface and countersunk head, as well as a conical-shaped bearing surface. Depending on the application, some manufacturers have a small increase in the top of the head to add extra strength around the recess for added driving power. Wafer Head for applications requiring extra clamping force. (ex. hanging cabinets plus door and window hardware/brackets.)

Hex Washer Head

The six-sided hexagon-shaped head is normally driven with a socket bit. Some hex heads have serrations on the bearing surface that help bind the head to the wood. They are often used in bunk bed and chair production. Some TV cabinet manufacturers also use smaller hex heads to attach the rear panel to the cabinet.

Hex Head

The flat underside of the head will accept a washer that will help create a larger load bearing surface than just the head or a Hex Washer Head Screw.

Pancake Head

Slight countersunk underneath head creates a stronger fastener. Uses include securing clips to wood used in standing-seam roofing

Confirmat Head

They have deep threads on an oversized shank, a clearance-hole diameter shoulder beneath the head, and a head that is just slightly larger than the shoulder. Installation requires a special three-step drill bit, but the result is a tight, strong joint.

Euro Screw

These screws are made specifically for use with the European 32mm cabinet components and perfectly fit the standard mounting holes on Grass® drawer slides, as well as most other brands.

Pozidriv (sometimes misspelled “Pozidrive”) is similar to a Phillips Drive. The GKN Screw and Fastener Company developed to address the common problem with Phillips, “Cam Out.” Cam Out is when the bit slips out of the recess, and the torque exceeds the forward pressure to keep the bit in the recess.

Pozsidriv bits differ from Phillips in that they feature small ridges inside each cross-section. These small ridges help provide better contact with the recess surfaces, providing greater torque and less likelihood of camming out than a Standard Phillips. Pozidriv is similar to Phillips in that both have the same self-centering design.

How do you tell the difference between Pozidriv and Phillips? Looking at the Head Recess, Pozidriv will have 4 notches cut in the head between the recess notches.

Can you use Pozidriv Bits to drive Phillips screws and vice versa? The two different drives do not have the same shape or depth of recess. You can, and the potential of slippage is much higher than if you use the correct bit. That being said, we do not recommend doing that.

Modified Truss Head

Modified Truss Head Screws are commonly used in applications like attaching metal lath to wood where the opening on the lath will allow small heads to pass though.

Slotted Recess

Slot screw drives have a single horizontal indentation (the slot) in the fastener head and is driven by a "common blade" or flat-bladed screwdriver. ... The slotted screw is commonly found in existing products and installations, along with use in simple carpentry work and in applications where minimal torque is needed.

Robertson Square Drive

In 1908, P. L. Robertson began to manufacture a square recess impression in the head of a screw in Milton, Ontario, Canada. He was a brilliant toolmaker that injured his hand while driving a slotted screw and started developing a better recess. At that time, it was a revolutionary change in the fastener industry. It has a more positive fit that reduces "cam out" and requires only 4 foot pounds of pressure to keep the bit engaged. An early attempt to introduce these Square Recess Screws into the United States failed so they were confined to the Canadian Market until the 1970s. The Phillips Head was introduced in the 1930s and would “cam out” instead of being over torqued by the new power drivers of the time. Henry Ford tried out Square Drive and found it to save time in the production of the Model T. Ford wanted to license the Square Drive, and when Robertson refused, Ford went with Phillips and allowed the Square Drive to be used in Ford's Canadian Production. For the auto industry, that was fine, where woodworkers were concerned about the finished look of their product. Eventually, the Robertson Recess screws migrated across the border making their place in the furniture and woodworking trades, especially with the growing popularity of pocket hole joinery. A new hybrid combines the Square-Phillips, Combo, or Recex Recess, which you can use for either Square/Philips bits. The first patent was issued in 1909, and the last patent expired 55 years later in 1964. For his invention, P.L. Robertson screws and screwdrivers carry his name to this day.

1.The Evolution of the Screw and Screwdriver

Phillips Recess Drive

It remains very popular in the woodworking industry. It provides a much more positive fit than slotted screws and requires about 12-foot pounds of pressure to keep the driver engaged in the recess. There is also more "'cam out" (driver bit slippage) that occurs when compared to square drive screws which offer a more positive bit engagement. This "cam out" was a part of the design feature to prevent overtightening of the fastener. This was described as a feature in the refinement Patent of 1949.

Pozi Recess Drive

Pozi Drive is commonly found in European drawer slide screws and hinges. A Downside to the Pozidrive is that it looks very similar to a Phillips recess. People will often use a Phillips bit on a Pozi Drive or a Pozi Drive on a Phillips. While they are slightly compatible, using the wrong driver bit can have damaging results. Either the screw is damaged, or the screwdriver or driver bit will be damaged. The Pozi Drive has four tell-tale marks on the head of the screw, which radiate from the recess. Their purpose is to let you know it is a Pozi Drive and you should use a Pozi Drive bit. Frequently used in Euro screws and metric fasteners. We frequently hear stories of people using a Phillips drive bit on Pozi recesses and reaming out the recess. It is officially called a Type IA crossed recess.

Comb or Phillips Square Recess Drive

A square bit is used to insert the screw and a Phillips driver can be used to remove the screw at the after-market level. Like the square drive, Recex® requires a minimum amount of pressure (appx. 4.5 foot pounds) to keep the bit engaged in the head. This reduces the possibility of carpal-tunnel syndrome for workers that drive screws all day long on a production line.

Torx Recess

Torx recess fasteners have become the automotive industry standard because they are easy to install with automatic assembly equipment or by hand. Torx-style fasteners are now used in most consumer products as well. Keep a few of these in your toolbox, and you’ll be ready the next time you need to disassemble an appliance (or your car). The new Impactech™ line of driver tools from Vega is specifically designed for impact driver use. The patented spiral torsion zone on Impactech™ products absorbs the impact driver load, resulting in extended tool life for the user.

Spax T-Star Plus

The SPAX T-STAR plus recess offers all the advantages of the SPAX T-STAR recess (no cam-out effect, minimisation of the contact force, absorption of high torques). In addition, this recess has a small depression in the screw head below the drive surfaces into which the matching SPAX T-STAR plus BIT with guide cone (or centre pin) can be precisely inserted. This SPAX T-STAR plus connection ensures the optimum torque transmission, a long service life for the SPAX T-STAR plus BITs, and a perfect fit. Even working overhead is easy, as the screw is guided much better and can no longer fall off the BIT.

Hex and Hex Washer Head Woodworking Screws

The underside of the head has a washer face to allow the load-bearing underside of the head to seat flat on the washer and help spread the load.

LOX® Recess

LOX® recess is a Grabber innovation patented for superior bit grip on Grabber fasteners. The eight points of contact between the LOX bit and the LOX recess act like a magnetic grip and provide a solid driving experience at any angle.

Cut Threads

Cut thread is the oldest way of making screws. Cut thread uses a larger diameter wire and cuts material away for the thread. Cut threads generally require the use of tapered drill bits to ensure proper holding power. The only cut thread screws we carry are the Flat Head Slotted Brass FSW, the Silicon Bronze Boat Building Screw SFC, and the Brass Cut thread BFC lines.

Rolled Threads

Rolled thread uses smaller wire and rolls the wire through dies to squeeze the threads onto the shaft. Rolled threads produce threads proud to the shank of the screw. These tend to hold better and can be used with a standard pilot hole drilled with a straight bit.

Traditional Wood Screw Threads

Threads on these screws are deeper near the point and begin to shallow as they get closer to the unthreaded shank or screw head.  Tapered drill bits are needed with this type of screw as the pilot hole should fit the outside shank diameter of the screw almost perfectly.  Creating this tight fit on traditional wood screws yields maximum holding power.

Drywall Screw Threads

Coarse threaded Drywall screws are used for attaching sheets of gypsum or “Drywall” to wood studs. Coarse thread screws are better suited for wood stud framing. Coarse thread screws drive into wood slightly faster than fine-thread and bite stronger in the wood below.

Fine threaded drywall screws sometimes feature smaller heads and are used to secure drywall to metal studs.

Fine thread screws can be used when installing drywall on wood studs, but coarse thread drywall screws cannot be used with steel stud framing

ProMax® Screw Threads

The screws normally used to install 2x4s or 2x6s for decking are 3 in. long and have 1 in. of unthreaded shank. Since 2x4 and 2x6 deck material are 1-1/2 in. thick, the threads bridge the joint, resulting in either uneven and unsightly surface or screws that are over-driven trying to "pull the board down. ProMax screws are different. Thread length is optimized to eliminate cross-threading. Plus, the 1/8 in. L system allows the use of the longest possible screw.

Saw Tooth Threads

Tiny saw blades are formed into the first three to four thread revolutions that cut through wood while displacing a minimum amount of material. By displacing less material than a Type-17 point, the ProMaster thread design offers greater holding power. Our testing shows that it offers 15% more holding power than a double Type-17 screw sold by our competitor while eliminating splitting. This new revolution in thread design technology was developed for Deerwood Fasteners and is very popular in the furniture and woodworking industry for its ease of driving while offering optimum holding power.

Pocket Hole Threads

Choosing the right screw, just like drilling the right size and depth hole makes your joint strong while the Type-17 Cutting Flute Eliminates Splitting.

Coarse-threaded pocket screws provide a hold better in softer woods, such as pine, cedar, and poplar, as well as plywood. Why the PocketMax works in booth soft and Hard Woods - PocketMax® screws are heat-treated making our screws tough enough to drive into Red Oak without a pilot hole (while we don't recommend that), yet tough enough to resist the forces trying to blow apart the driver bit recess as the screw is driven in, tough enough to resist breakage when a load is applied to the joint. They have an oversized (thickness, Undersized on diameter to prevent draging on the wall s of the Pocket Hole) Fillister (sometimes called "Cheese") head to minimize crushing in softwoods, extended unthreaded shank to avoid cross threading or board jacking, and have superior holding power to a washer head screw. Go into most hardware stores and home centers and the screws you find will be poorly heat-treated, or not heat-treated at all!

Fine-threaded screws for Hardwoods like Cherry, Maple, Oak, Walnut.

Our Super Eight Threaded PocketMax Screws work well in MDF, OSB, and Particle Board.

For outdoor applications, choose stainless steel or coated screws. Never, ever use drywall screws. "Drywall" screws are designed to penetrate a layer of powdery drywall and a soft wooden or thin metal studs. Drywall Screws are hardened with a thinner shank than pockethole screws. They can and will break easily while driving in a non-drywall application. Their Bugle Head can split the bottom of the pocket shoulders, ruining your joint.

Type 17 Screw Point

A slot or notch is cut out at the point of the screw that acts like an auger or drilling tip. The slot carves away the material, thus allowing it to self-drill into most types of wood. It can often eliminate the need for a pre-drilled hole to relieve splitting. The Type 17 point is excellent for hardwoods, softwoods, particleboard, and especially MDF. Type 17 points are commonly available today in our Deep Thread style and are quickly becoming the fastener of choice for the woodworking professional. There are many advantages to the Type 17 point, but the process of seeing the slot into the shank and threads is slow, and the additional expense must be compared to the benefits. As a "rule of thumb," the add-on for shank slotting is around $2.00 to $3.00 per 1000 pieces. If pre-drilling can be eliminated, then the cost savings can be justified. Production costs for having a worker drill 1000 holes by hand generally exceed $2.00 to $3.00 at the standard hourly rate.

Coarse or Deep Screw Threads

Coarse Thread or more accuratly, a Deep Thread is a single lead thread, meaning that one revolution advances the screw one pitch. (Pitch equals 1 divided by the number of threads per inch. For a screw with 10 threads per inch, one revolution will advance the screw 1/1O in. into the wood or said another way, it will take 10 revolutions to advance the screw 1 in. into the wood.) The deep thread form provides superior resistance to pull-out.

The deep thread form provides superior resistance to pull-out. This design feature is commonly called a Lo-Root® or Production Screw.

Twinfast Threads

One revolution advances the screw 2 pitch lengths advantageous on long screws or in situations requiring rapid assembly. 'Drywall screws typically use this thread since pull-out strength isn't as important as speed. These screws lack the pull-out resistance of "Deep" threaded screws like our Deep Thread or ProMax® screws. Typically, #8 and #10 screws 4 in. and longer use this thread because of the increased strength afforded by the larger shank diameter.

SPAX® Cut Point

This is achieved through its special screw tip. The arrow shape pushes through the fibres of the wood, ensuring a fast grip. This effectively prevents the material from splitting and reduces the insertion moment. For hardwoods, we recommend pre-drilling even when using SPAX with 4CUT.

Composite Deck Screws Reverse Threads

Cap-head prevents mushrooming and material from rising up above the deck for a smoother, clean-looking installation. Approved fastener (by Trex®) for Trex® composite decking

Drill Point Screw Threads

When selecting a self-drilling screw, consider the material thicknesses and types of materials to be joined. Following are some key design features to look for when selecting suitable fasteners.

Drill Flutes allow drilled material to exit the hole. Completely embedded flutes can no longer remove these chips, which contain approximately 80% of the heat created by the drilling process. A buildup of this material can cause the point to overheat and fail.

Point Length determines the material thickness which the screw can reliably penetrate. The unthreaded portion of the point (pilot section) must be able to drill through the material completely before the threads engage. If the threads engage before drilling is complete, the fastener can bind and break.

Point Wings are used on some screws that fasten thicker materials, such as wood, to metal. The wings enlarge the hole in the fastened material, allowing the threads to pass through without contacting the fastened material. This added clearance prevents separation of the fastened material from the base metal (known as “jacking”). The wings will break away on contact with the metal before the threads engage with the metal.

Drill-Point Material is generally plain carbon steel, which is less stable at high temperatures than equivalent high-speed steel (HSS) drill bits. To reduce wear on the drill point, fasten using a drill motor rather than an impact driver or hammer drill.

Traditional Lag Screw Threads

Traditional Lag Screws – Lag Screws, at times referred to Lag Bolts (which have a machine type thread pattern to accept a nut or thread into another piece that has matching threads), are used to connect heavy lumber that are bearing an intense load. These screws differ from traditional screws that are usually self-drilling and require a drilled pilot hole to accept the thickness of the shank before inserting the Lag into the joint. When drilling the hole, the joint will have to be clamped or held together while drilling the pilot hole and then driving the lag screw into place. These usually have a Hex Head on them so that they can be driven using a wrench (have a good breakfast before doing it this way) or socket on a ratchet or impact driver because of the force that is required to thread them into the joint. Lag Screws have a sharp point and are available in several finishes/coatings for corrosion resistance.

Type B Threads

Confirmat screws come with a Type-B thread style to insure maximum thread engagement in a pre-drilled hole.

SPAX Double Threadlok

GRK RT Composite™ Trim Head Screws

RT™ Reverse Thread Trim Head Screws are optimized for use with all Composite, PVC and Capstock Decking and exterior trim. It leaves a clean look as the tiny heads disappear when countersunk.

Simpson Strong-Tie SDWS Timber Screw

including ledgers, and is also ideal for a wide variety of projects requiring a high-strength attachment. This structural fastener has been redesigned with a patented SawTooth™ point, providing faster starts with less torque. Also, with its 0.220 in. shank diameter, this fastener is easy to drive, and the corrosion-resistant coating makes it suitable for many interior or exterior applications.

Box Threads

which allows you to drive more screws on a single battery charge Specially-designed sharp point penetrates hard wood products with ease.

Euro Screw Threads

Euro Screws are identified as 5mm and for some that can be confusing. They are designed to fit a 5mm hole in drawer slides and hinges. The Minor Diamiter on these screws is 4.00 to 4.20 and the Major Diameter is 6.30 to 6.55 allowing the screw to pass through a 5mm hole. The head is designed to fit the stamped hole in drawer slides and hinges. If you use these screws is other applications and drill and countersink the hole, you may not get a goot fit that you are looking for.

Box Thread with Raised Ridge

Unique “box” thread design with raised-ridge technology greatly reduces driving torque, which allows you to drive more screws on a single battery charge. Specially designed sharp point penetrates hardwood products with ease. Use with wood, engineered wood, and polymer materials

Simpson Strong-Tie Double Barrier Coating

¹The specification ASTM A153/A153M applies to hardware products such as castings, fasteners, rolled, pressed, and forged products, and miscellaneous threaded objects that will be centrifuged, spun, or otherwise handled to remove excess zinc.
The requirements for ASTM A153/A153M are very similar to those stated earlier for ASTM A123/A123M, except for the addition of threaded products and embrittlement requirements.

ASTM A153/A153M Requirements

• Coating Thickness/Weight  depends on the material category and steel thickness, values are listed in Table 3
• Threaded Products  areas with threads are not subject to the coating thickness requirement
• Finish  continuous, smooth, uniform
• Embrittlement  high tensile strength fasteners (>150ksi) and castings can be subject to embrittlement
• Appearance  free from uncoated areas, blisters, flux deposits, and gross dross inclusions as well as having no heavy zinc deposits that interfere with intended use
• Adherence  the entire coating should have a strong adherence throughout the service life of hot-dip galvanized steel

Table 3

Ribs & Knurls

to dispose of or eliminate the particles causing the bulge before the head gets flush with the material. This is very similar to the Nibs found on the underside of a Flat Head Screw.

Truss Head Break Away Screw

These are perfect for mounting drawer pulls and other hardware items that do not require significant strength. The shank of this 8-32 truss-head machine screw is scored at 3/4", 1", 1-1/4" and 1-1/2" so the unneeded length is easily broken off, leaving a clean thread. Head diameter is .95 – 1.12", thickness is .364 – .384".

Dowel Screws

Use dowel screws to connect two wooden parts that have blind holes, such as the finial on a stair railing. Dowel screws over 1-1/2 in. L are unthreaded in the center, making installation with a pair of locking pliers easy. Note: Finial is not included.

Dowel Screw Specs

Hanger Bolts

Hanger bolts have wood screw threads at one end and machine threads at the other. Screw one end into wood, and the exposed end provides a machine-threaded stud. All bolts have an unthreaded center to make installation easier. Note: The corner bracket is not included with the hanger bolt.

Hanger Bolts Specs

Carriage Bolts

A carriage bolt (it has a Type B Point and uses a Nut to complete the fastening process) is used for wood-to-metal or wood-to-wood fastening. It has a domed head with a flat underside and a square neck on the top of the shank. The flat underside provides a load-bearing surface on the wood while the square prevents it from turning by recessing into the wood. This prevents it from turning while tightening the nut and completing the joint. Use stainless steel carriage bolts in seaside applications or where corrosion resistance is important; use hot-dip galvanized carriage bolts for freshwater docks, inland deck,s and other outdoor structures. Torque washers are recommended for use with softwoods like pressure-treated lumber.

Type A Point

Its symmetrical thread pattern with a 30° top and bottom angle offers good holding power in metals and plastics. This type of thread style is being used less in the woodworking industry due to the popularity of "Deep Thread" screws designed to offer optimum holding power. The length tolerance on a Type A screw is plus or minus 1/16'' unlike woodscrews that have a +0"/ - 1/16" to +0 / -3/32" based on length.

Unplated Hardened-Steel

Their color variation from almost pure black to bronze to silvery gray does not affect quality − it is simply a result of process-variable interactions as simple as the screw’s location on the heat-treat furnace conveyor belt. All McFeely’s unplated screws receive a dry-lube coating, which reduces driving torque requirements but provides virtually no corrosion resistance. Hardened-steel screws are the base stock for all of our plated screws.

Stainless Steel Wood Screws

Although all products c01rnde sooner or later, stainless steel provides excellent protection. Since the carbon content of stainless is quite low, oxidation (rusting) is also quite low. However, the steel cannot be heat-treated to adequate levels because of the low carbon content. As a result the screws are soft and break easily when used in wood applications where high levels of torque strength are required. Pre-drilling all screw holes and using larger gauges of screws can compensate for this problem.

Type 410 Stainless Steel

Type 410 stainless steel is a low-carbon martensitic grade of stainless steel that can be hardened and is inherently magnetic. This material provides corrosion resistance in mild atmospheres and many mild chemical environments.

Types 304 and 305 Stainless Steel

Types 304 and 305 stainless steels are nickel-chromium austenitic grades of stainless steel. Types 304 and 305 stainless steels are inherently nonmagnetic and not hardened by heat treatment.

They provide very good corrosion resistance and are suitable for use in many corrosive environments. Fasteners made from Types 304 and 305 stainless steels are compliant with the 2012 and 2015 IBC and IRC.

Type 316 Stainless Steel

Type 316 stainless steel is a nickel-chromium austenitic grade of stainless steel with 2-3% Molybdenum. Type 316 stainless steel is not hardened by heat treatment and is inherently nonmagnetic. It provides a level of corrosion protection suitable for severe environments, especially environments with chlorides. Type 316 stainless-steel fasteners comply with the 2012 and 2015 IBC and IRC. See Passivation of Stainless-Steel Fasteners below. *

* Passivation of Stainless-Steel Fasteners - Stainless steels are designed to naturally self-passivate by forming a chromium oxide layer. Corrosion resistance of some stainless-steel fasteners is enhanced by a post-fabrication passivation process. The passivation process uses an acid bath to strip free iron from the surface and an oxidizer to force conversion of the surface chromium to the oxide form.

When should I use stainless steel screws?

• Use of 305 stainless steel screws are recommended for use in Ipe, Treated Lumber, Cedar, White Oak, and any hardwood.
• Anything within 1 mile of the coast should use 316 Stainless Steel fasteners, and anything within 15 miles of the coast should use 305 Stainless Steel fasteners.

We carry stainless steel in a variety of grades. Note that not all grades are designed to be completely “stainless!”

Solid Brass Woodworking Screws

(Pre-threading the hole with a steel screw helps minimize this problem). A Square recess really makes a difference with these screws. The softness of the brass greatly increases cam-out problems with most other driver types, a situation neatly overcome by the Square recess.

Silicon Bronze Woodworking Screws

Although many people have used them to build decks made of Western Red Cedar or Redwood because the screws will eventually blend into the color of the wood. As pictured, screws right off the production line are generally the color of a fresh penny. After they’ve been around a while, they oxidize and darken.

Lube or Dry-To-The-Touch Finish

Our Lube finish is a dry-to-the-touch lubricant that offers a reduction in driving torque and a finish that does not interfere with dust collection systems or bleed during the staining process of fine woodworking. More economical than plated parts, they are a popular choice with professional woodworkers. They are a brownish color that allows them to blend well into wood.

Black Finish Woodworking Screws

It serves as a conversion coating through a process where it is dipped or sprayed with a dilute solution of phosphate salts or phosphoric acid is applied to create a chemical reaction with the surface of the part being coated creating a layer of insoluble, crystalline phosphate. The Phosphate process is more Eco-friendly process compared to the oxide process and because of the chemical reaction that happens, it is less likely to rub off when compared to Black Oxide.

Statuary Bronze Woodworking Screws

Highlights increase on screws xposed to wear or abrasion.

Yellow Zinc Woodworking Screws Finish

It offers a modest amount of corrosion resistance (approximately 100 hours’ salt spray to 10% red rust). It is basically a secondary “colored” plating that is plated on top of a clear zinc base, hence the additional corrosion protection.

Bright Brass Woodworking Screws

It provides little corrosion resistance, although, in highly acidic woods like Red Oak, it can prevent the dark blue stains that sometimes form around an unplated screw.

Clear Zinc Woodworking Screws Finish

A good choice for interior applications when working with acidic woods like Red/White Oak or when the screw will be countersunk and plugged. It is a poor choice for most exterior applications.

NoCore Plus Woodworking Screws Finish

In manufacturer-conducted salt-spray testing, it has exceeded 1,800 hours, making it almost 20 times more corrosion-resistant than standard yellow zinc plating. It works well with most outdoor woods, including ACQ pressure-treated wood. Use caution with Redwood, Western Red Cedar or similarly acidic woods − these tend to stain, sometimes even with stainless! And unlike the plating on hot-dipped galvanized screws, NoCoRode Plus doesn’t chip and you won’t find the recesses full of plating material that makes the fasteners useless. Best of all, the plating is tan colored, so it “blends” with many pressure-treated materials.

Kreg Blue-Kote™ Woodworking Screws

Blue-Kote™ Screws provide rust-resistance up to 400% greater than zinc-plated screws and work with pressure-treated material.

Spax HCR-X™ Coated Screws

It offers similar corrosion protection to that of SPAX® HCR® coating in that it has been approved for use in freshwater environments and for use in treated lumber. Note: HCR-X™ from SPAX® is typically grey/silver in color.

SPAX HCR™ Coated Screws

The first barrier is an electrically applied substrate with a proprietary organic topcoat offering 1000 hr. salt spray performance. NOTE: HCR® from SPAX® is typically green in color.

Double-Barrier Coating by Simpson Strong-Tie

that is equivalent to hot-dip galvanization (ASTM A153, Class D) in most non-marine environments.

Hot Diped Galvinized

Stainless Steel bolts, lag screws and hex-head cap screws are typically made of 18-8 grade stainless − it offers good corrosion resistance and machines rather easily. It may show some evidence of staining, but it is an acceptable fastener, especially when used with ACQ pressure-treated materials. Use only passivated stainless fasteners below the waterline to avoid severe corrosion and eventual failure. McFeely’s® stainless fasteners have been passivated so that this is not an issue.

Hot-Dip Galvanized fasteners have been the standard for heavy-duty applications for many years and still perform well. They are most often used with pressure-treated materials for inland structures or those around freshwater. Threaded connections are slightly sloppier than stainless fasteners to accommodate the variabilities of the galvanizing process. Our hot-dip galvanized fasteners have a minimum tensile strength of 60,000 psi and conform to either ANSI/ASME B18.5 (carriage bolts) or ANSI/ASME B18.2.1 (lag screws and hex-head cap screws).