Drilling
Drill presses used to be a machine that were only in the reach of cabinet shops or school workshops where the expense of these machines could be justified. In the past 20-30 years, with manufacturing in Taiwan and now China, the cost of woodworking machinery overall has dripped so much that drill presses are now in the reach of most woodworkers.
Drill presses on the market today can be used for a wide range of applications, including drilling in wood, metal and plastic. The first most important question is “What am I going to be using it for?” The second important question to ask is “How often will I be doing it?”
There are two major types of drill presses commonly available from most suppliers. The first type is a fixed head drill press. These are the drill presses most commonly found. The second type of drill press made popular recently by a huge reduction in price is a radial drill press.
Radial drills have a head that can be adjusted fore and aft of the supporting post to increase the drilling depth from the edge of the board. This design overcomes a limitation found in fixed head drill presses, but this design also provides limitations of its own.
When deciding on what type of drill press to settle on, the most important question to ask is, how far do I want to drill from the edge of a board? Fixed head drill presses can drill as fas as 105-254mm from the edge of a board (depending on what model you choose). This should be ample if you are working mostly in solid timber. Radial drills, however, can drill up to 425mm from the edge of a board, great for drilling in panel product. Fixed head drill presses also generally have more speeds over a greater speed range too, meaning that you will be able to drill into metals and plastics with ease, by matching the material to the correct speed.
Radial Drill Presses
Radial drill presses are a machine originally developed and manufactured by Delta machinery. These drill presses have become widely accepted around the world now as a popular type of drill press. Radial drill presses are only suitable for woodworking due to their speed range. Because they do not have a fixed head a third pulley cannot be installed, thereby limiting the number of speeds from 12-16 (found in fixed head drill presses) to five.
The first noticeable feature a radial drill press has is the head design. The motor and drilling column are mounted on a round 70mm ground steel post. This is then mounted to a housing at the top of the support post, which allows for fore and aft adjustment of the chuck.
The adjustment is made via a graduated rack on the bottom of the post, allowing easy and fine adjustment of the head. It is then locked I place when adjusted correctly to ensure there is no movement when in use, allowing accurate drilling to occur. There are two benefits of this design; firstly, that the chuck can reach into the centre of a 850mm wide board, something fixed hear drill presses have never been able to accomplish. The second is that a series of holes can be drilled in a row. This is great for drilling holes for shelf supports or for drilling multiple square holes when used in conjunction with a morticing attachment.
Another benefit of a radial drill pres is being able to change the orientation of the head. The head is traversed via a round post and this also allows for the head to be tilted at any angle required. Radial drills usually have stops included so that it can be rotated at 90° and 45° without any measurement required. It can also be set at any angle in between this jut by tightening a locking handle. This is great for drilling into unusual work pieces or even as a way of drilling the popular packet holes for blind jointing you can set the head at a 15° angle, hold the work piece vertically as it would clear the head and drill as you normally would. This is not commonly known, but shows their versatility.
The unique feature of a radial drill press is also its limitation. Because the head is not fixed and therefore reinforced, radial drill presses tend to vibrate when drilling in heavy applications. This can be limited by fixing the base down to the bench or floor, and also by drilling slowly when boring large holes.
It is recommended to use bits only up to 75mm diameter with radial drill presses as these machines tend to lose their effectiveness with bits any larger than this.
Radial drill presses are usually provided with one specification choice from most suppliers. Bench models and floor models usually share the same specifications but have a different length post for each model. Sherwood has ensured that you are not limited to smaller drilling applications with the choice of a radial drill press. Most available only come with a ½ hp motor, the Sherwood varieties come with the common ¾ hp motor.
Fixed Head Drill Presses
Fixed head drill presses are available in a wide range of different sizes to suit different user’s wallets and requirements. It is important to work out the correct motor size. The average size woodworking drill bit is 35mm diameter. As a guide this can be run in a drill press on a production basis with a motor size of 550W (3/4hp). This is the most common size motor found on drill presses today. If you don’t think that you will ever need to drill a hole that large or won’t need to drill it very often, then a smaller size motor would be suitable. If you wish to drill larger holes than this on a regular basis then you will need a larger motor size. Throughout tests done here, we find that a ¾ hp motor is suitable for almost all drilling applications, the larger the size of the bit the slower the speed and a reduced pressure when drilling will allow the drill to perform the task well.
All Sherwood drill presses feature alloy bodied motors. Alloy-bodied motors run cooler than cast iron bodied motors, and as a result, motor life is increased due to less heat-stress within the motor itself.
This feature is very important when drilling for an extended period of time.
Fixed head drill presses usually have three pulleys in the head to allow for 12-16 speeds. The pulleys should be machine balanced with fully sealed bearings for long life. Generally the speeds range from 210-2580rpm.
This speed range makes fixed head drill presses suitable for metalworking, woodworking and drilling in plastics. The motors are usually suspended on a track so that when tension is released, the belts can be changed to the correct pulley to select the correct speed. All Sherwood drill presses use two tracks to support the motor to ensure that the pulleys remain parallel. It also provides extra support for the motor, which will reduce the vibration found in drill presses. Most standard drill presses us a ½ in drive shaft to drive the chuck, heavy duty drill presses uses a 5/8 in shaft to increase stability in large boring applications.
Fixed head drill presses have components of varying sizes, to cope with the drilling applications they have been designed for. The head, supporting post and base are usually the most important features that absorb vibration. The head size is calculated for length by the swing (distance between the centre of the chuck and the inside edge of the post), limiting the drilling depth from the edge of the work piece. As drill presses have increasing swing, a heavier post is required to support the head and table effectively and a larger base to ensure the drill press remains stable on the floor (or bench). It is generally recommended to fix the drill press to the bench or floor as appropriate to increase stability even further.
The height of the head of a drill pres is determined by the travel of the chuck (the maximum distance the drilling bit can travel into the work piece). As the travel increases the head needs to be a certain height or allow for accurate travel downwards and to ensure the shaft does not vibrate when fully extended.
If you are unsure of what size drill press you may need, please always allow for an increase in your ability and expanded drilling applications. Drill presses are usually so well designed and built that you will only ever buy one, unless the drill you buy can’t keep up with your growing abilities. As time moves on drill presses have become more versatile with the addition of attachments and new styles of boring bits. Spending extra on a drill press now may save the need to buy a whole new unit in a number of years.
Specialty Drilling Presses
Cross Slide Vice
A draw back of standard drill press vices is that once they are fixed to the table it is hard to locate the drill bit directly above the place on the work piece that needs to be drilled.
Cross slide vices solve this problem easily.
Cross slide vices are fixed down to the drill press table just lie a standard drill press vice, but have two sliding mechanisms integral to the base. This allows the user to clamp their work piece into the vice, and then, via two well-located hand wheels, can be adjusted either laterally or longitudinally. This allows the user to position the work piece directly under the bit, thereby dramatically increasing accuracy.
Angle Vices
While radial drill presses can tilt their head and some fixed head drill press tables can tilt – the easiest option is to use an angle vice. It tilts from any angle 0-90° and is adjusted via a quick-lock handle on the side. It can add another dimiensio to accuracy when drillinad provide you with more optionsin your woodworking.
Drill Press Vices
Sometimes you just need an extra pair of hands on your drill press. A standard drill press vice mounts to the table and holds work pieces securely in place when drilling. It doesn’t offer you the freedom to move the pieces when clamped, but is a good cost effective option. Shown here with the recommended (optional) soft jaws – that stop your work from being marked by steel jaws found on all drill press vices.
Drill Press Support
A common criticism of drill presses are their small tables – making it difficult to suport long work pieces easily. By attaching this suppor to your drill press post, you get good support on both sides of the table for long pieces. It can be extended or retracted depending on the length ot the work piece and the rollers make it easy to move the work piece.
A great addition to your drill press!
Bits & Accessories
A wide range of boring bits and accessories are available for drilling timber and panel board. We have supplied information on the most common types of wood boring bits available on the market. If you require any further information on a specific type of bit or a bit that you are interested in, please contact our sales staff and we will be happy to help.
Twist and Brad Point Brill Bits
Twist drill bits have long been used in woodworking applications as these are the most common type of standard drill bits available on the market today. Whilst twist drill bits can bore through timber, they were originally designed to be used for metalworking. Because timber and metal have different properties, a different type of drill bit has been developed specifically for woodworking - the brad point bit. Due to a lack of worldwide demand brad point bits are not available in as wide a range of sizes as the twist drill bits and wher the choice of a brad point bit is not possible, a tweist drill bit can be used.
Brad Point bits are true wood boring bits. They are designed with a centre spur to locate the centre of the hole easily, and two perimeter cutter to cut the perimeter of the hole. Rather than allowing the cutting fact of a twist drill determine the path of the drill bit, these horizontal cutters ensure that the perimeter of the hole is the perfect distance from the centre point of the bit, allowing both a smoother and more accurate cut. The majority of the waste is taken away by scrapers located between the centre and outside spur. On some brad points these scrapers are horizontal, but can also be shaped with a negative rake which allows for faster chip ejection. This type of design allows for faster, smoother and more accurate drilling applications.
Spade & Forstner Bits
Spade bits are an economical method of drilling large holes into timber. They feature a similar design to brad point bits but lack the outside rim to guide it effectively through the timber. Spade bits are usually found with one centre spur to locate the bit easily and horizontal scrapers to remove the waste. A good quality spade bit also has two spurs on the outside, which, just like brad point bits, allows for a more accurate hole in the timber as it can guide the bit through the timber.