Lewis Wood Augers – 20mm Diameter – 13mm Hex Shank
The Auger bits have one taper tap, one main cutting edge as well as a crest of thread, which is particularly suitable for soft wood and European hard wood. The mode of operation is similar to the Forstner Bit: First the taper tap will pre-cut the wood fibre of the outer cross ring, then the main cutting edge will do the main work.
The Augers are ideal for carpenters, automatic carpentry machines and anywhere where people need to drill deep holes in wood. The shafts are manufactured with a hexagonal shank, in order to avoid the shaft twisting in the machine (from diameter 10mm).
Auger bits can be custom made to your requirements with up to 2500mm length and 80mm diameter a feasible option.
Our Lewis pattern are characterized by a milled helix. This kind of helix warrants the highest bending stiffness at maximum chip space. Therefore our Augers Bits temove the wood chips without any problems.
History of the Auger Bit
Auger Bits are indispensable if you want to drill especially deep holes in wood. They have a large coiled chip space, whereby the chipped wood are carried out to the tool shank during the drilling. In the following History we will inform you about three different auger bits, which differ according to the type of helix.
1909 the “Lewis-Drill-Bit” (patent since 1809) illustrated in the catalogue of the company “Weiss and Sohn”. The wide difference between this and other auger bits was that, the auger had a coil with a free centre and one main cutting edge.
1855 a patent for another type of auger the “Douglas” was patented in Germany. This Auger bit was manufactured by twisting flat bars. It has a double-thread helix, two taper taps and two main cutting edges.
1884 Charles Irwin received a patent for his snake bit and invented the third option. This drill has a round central shaft with a circular spiral. Distinctive in that the helix emanated only from a main cutting edge. The spiral of the second main cutting edge ended after a half turn. Due to this trick a very large chip space was created which transported the chips very well.
Today, because of the universal characteristics and the modern manufacturing techniques, only the milled “Lewis” Auger bits are readily available.