Originally, each boring tool would make one size of hole, just like the gimlets (above).
The invention of a drill chuck, which could hold individual drill bits, paved the way to a less bulky solution to boring lots of different sized holes.
With a profusion of corded electric, and cordless electric 'drills' available today, it's quite possible for the unplugged boring tools to be unheard of.
I encourage everyone taking up woodworking to try as many as possible, and discover which suit them best in different situations.
Single hole diameter tools:
Awl |
When pushed fully in/through, a hole the diameter of the shaft is formed. However, as no waste is removed, the hole wall will spring back to some degree once the awl is withdrawn.
Hole location is very accurate.
The Bradawl
A tool with a flat blade at the end of a shaft, rotated to bore a hole.The rotating blade severes wood fibers, some waste is removed, and there is generally less springback than with an awl.
Due to it's action, the bradawl is less accurate in locating the hole.
Gimlet or Screwawl |
The screw thread pulls the tool into the material, whilst the spiral flute cuts and conveys the spoil out of the hole.
Gimlets are available in a good range of sizes, covering smaller diameters.
These are quite accurate, and very easy to use.
Tip of a Gimlet |
Gimlets are essentially an auger bit with a handle.
Multiple hole diameter tools:
Hand drill (eggbeater drill)
Geared tool, with a chuck that can hold a range of drill bit diameters.Chucks can be either keyed or keyless, as shown.
Ideal for short, small diameter holes.
Some have hollow handles to store bits |
Brace |
Variants with different depth 'power' handles are available (e.g. a 12" brace, where the handle is offset 6" from the centre), balancing torque with tool size and arm movement.
A chuck, with v-shape clamps, holds bits with tapered square section ends, ensuring no chance of slipping under high torque.
Ratcheting actions are also available, making use in some restricted areas possible.
Cordless Electric Drill |
Mains Electric drill
Predominantly using a universal motor, these drills work best at high rotational speeds, where, with suitable bits, they can out perform the brace in terms of hole diameter and speed. However, the speed and bit design can make them harder to keep aligned, and prone to over-heating. High Speed Steel (HSS) bits are most certainly recommended, and care should be taken to avoid burning the wood.Stationary Boring Machines
The previous tools are all hand held, but for boring holes accurately at angles or to depth, and for large diameters, stationary machines are to be preferred.
Small bench top drill press |
Floor standing drill press |
The distance between work table and drill can be adjusted to accommodate different sized work pieces, and it's angular relation to the drill shaft is usually adjustable for drilling angled holes (angled platforms can be clamped to a table that does not have this ability).
Accessory stand for mains drill |
Speed control is either electronic, or by manually adjusting the belt(s) on stepped pulleys. This control is necessary as the large diameter tooling, which should only be used in a stationary machine, has to be run at slower speeds. Also, when used for drilling different materials, the edge speed can be chosen for better performance.
Drill press stands are available as accessories to mains electric drills.
Drill Bits:
Left to right: Auger brace bit, Standard twist bit, Brad point bit, Spade bit, Forstner bit |
118° point angle twist bit |
The tip profile determines how easily and/or cleanly the drill will enter and exit particular materials.
For woodwork, the standard twist drill bit profile (point angle of 118°), and the brad point bit (lip & spurs), should cover most situations.
Brad Point (or Lip & Spurs) bit |
I recommend HSS tooling for all electric drills, as it is too easy to over-heat other bits.
Jennings-pattern Auger bit |
Also shown in the photo above were a spade bit (fast boring in softer woods), and a forstener bit (flat bottom holes (usually with a centre divot)).
Demonstration
The brace and hand drill are discussed and demonstrated in my YouTube video:
Thanks Mitch some great info mate
ReplyDeleteCheers Ken :)
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