Auger and Gimlet
Some time after Caesar's conquest of Gaul the writer Pliny mentions a "Celtic drill" {gallica terebra). This was probably the auger, as used by the Celts of Central and Northern Europe, who were much admired by the Romans for their skill as carpenters and wheelwrights.
The early augers were spoon-shaped at the business end and up to 18 inches long, with flat tangs or an eye to take the cross-handle. Later the spoon was twisted and drawn down to a point, as in the gimlet. The first true spiral or twist augers were invented late in the eighteenth century, but took some time to develop owing to manufacturing difficulties. The "Jennings pattern" with spurs or nickers was patented by Russell Jennings in 1855 and the solid centre or "Irwin pattern" followed in 1884.
Auger
SIZE: Diameter: 3/4 to 1-1/4 in.
MATERIAL: Steel
USE: To drill holes in wood
Augers are used to drill fairly large holes in lumber. The boring end has a lead screw and twisted flutes like a drill bit to clear the waste. The common varieties are the "Jennings" pattern and solid centre augers. The shaft is about 24in. long with a collar at one end to take a removable handle.
Special end grain boring augers, up to 30in. long, are available. The thin, round-sectioned shaft is squared and tapered at one end to fit a handle. The other end has a shell bit fitted.
Gimlet
SIZE: 1/8 to 3/8 in.
MATERIAL: Body: steel: Handle: hardwood
USE: To bore holes in wood
The gimlet is used to bore shallow holes in lumber, often to take a screw. The shaft terminates in a spiral lead screw followed by a "shell" or spiral fluted section for cutting and removing the waste. The remaining shaft, running to the handle, is either narrower than the cutting end, or tapers to reduce the friction in the hole. The cross handle is formed by the shaft itself being twisted to the required shape or it is squared and tapered to fit into a turned hardwood handle. The end of the shaft is riveted over to fix it securely in the handle. The handle is held in the palm of the hand with the shaft projecting between the index and middle fingers.
To sharpen a gimlet, bore a 1in. hole with it in a piece of hardwood. Withdraw the tool and fill the hole with a mixture of oil and fine emery. Insert the gimlet to the depth of 1/2 in. and turn it backward and forward until the cutting edge is honed. For a very blunt gimlet you may need to top up the hole.
Using the gimlet
Bore a hole by twisting the tool until the lead screw pulls it into the wood. Twist in one direction only, not backward and forward as you would with a bradawl.
Taper Reamer
SIZE: 5-1/2 in.
MATERIAL: Body, steel; Handle: hardwood
USE: To ream a drilled hole
The taper reamer cannot drill a hole itself, but is used instead to enlarge and clean up a hole. Used from one side only, it will produce a tapered hole.
