Wood Screws - Versatile & Effective Fastners!

Millions of wood screws are made every day and in such varieties, finishes and sizes that we take them for granted. However, without these versatile and extremely effective fasteners, many industries, particularly the furniture and building industry would grind to a halt!

So what are screws and how did they develop? Well, a screw is essentially a threaded shank that grips the wood and is normally made from metal with some kind of 'driving' feature at the top.

Phillips & Posidriv Screws With Bits

In the 1st Century, screws were made from wood and used to fasten two objects, usually wood together. At the time, they were extensively used in olive and wine presses.

Metal screws were invented in the 15th Century and today are the norm. They are used to fasten a wide variety of modern materials including wood, plastic and metal.

Screw drivers are used to drive the screw, using downward or sideways pressure and can have various interchangeable bits depending upon the type of screw being used.

The flat bladed bit used in a carpenters brace first appeared in 1744 and was the precursor to the traditional screwdriver. Hand held screwdrivers first appeared in the 1800's.

Traditionally, screw drivers were used manually but today carpenters and joiners often use hand held power drills, as it's quicker and easier. Like the traditional screwdriver, different screw bits can be used to suit the screws being used.

The first, crude, screw cutting machine was invented in 1770 by an instrument maker called Jesse Ramsden. This resulted in further technological developments and in 1797 Henry Maudslay invented a machine that made it possible to mass produce screws.

Flat head screws have one slot. Raised head and round head screws are more decorative and are used where the head needs to be above the surface of the wood. A countersunk head means that the screw will be flush with the wood surface.

In the 1930's the Phillips screw was invented and is still being used today. The Phillips screw has a plain crosshead which is cut deeper into the head and was designed to increase 'grip'.

The Phillips company subsequently collaborated with the American Screw Company and developed the pozidriv screw, which has more indentations for even better grip and does not 'torque out'

The pozidriv screw is the most widely used wood screw today and is used with a pozidriv screwdriver that fits the screw perfectly.

http://www.polmacuk.com