14 x 2-1/2 Kreg Large Exterior HD Pocket-Hole - Qty:125

14 x 2-1/2 Kreg Large Exterior HD Pocket-Hole - Qty:125

Kreg Jig® HD Screws are optimized for use with the Kreg Jig® HD and 1-1/2 in. and larger stock.

These large 2-1/2 in.-long, #14 hardened-steel screws provide incredible shear-resistance, and have a Protec-Kote™ finish with three anti-corrosion layers for long-term moisture resistance. These screws can be used with Composite and pressure treated lumber.

#3 square driver.

The Type 17 point is not a thread style but can enhance the performance qualities of most thread styles used in the woodworking industry. 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 itself into most types of wood. In many instances it can eliminate the need for a pre-drilled hold to relieve splitting. The Type 17 point is excellent for hardwoods, softwoods, particleboard and especially MDF.

Round Washer Head Screws have an even larger bearing surface than Pan and Truss Heads. 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 on to the head to increase head diameter and prevent overdriving in softwoods while providing a maximum bearing surface.

Square Drive Recess: This recess was invented by P.L. Robertson (founder of Robertson, Inc.) in 1908 and was the first production fastener with an internal recess.

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 them to save time in the production of the Model T. Ford wanted to License the Square Drive and when Robertson refused, Ford went with the Phillips and allowed the Square Drive to be used in Ford's Canadian Production. For the auto industry that was fine where woodworkers work 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 is the combination of the Square-Phillips, Combo or Recex Recess that you can use either or 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