Hand drills and braces are available in a range of sizes suited to different applications, with smaller hand drills suited to more delicate work, and larger braces able to apply more torque for drilling larger holes.
How are braces sized?
A brace will be advertised with two sizes that you need to take into consideration.
Chuck size
The first is the chuck size: this determines what size bit can be fitted into the chuck of the brace. For example, a brace with a 13mm capacity chuck can be used with a bit that has a shank size of up to 13mm.
The second size you will need to know when buying a brace is the sweep.
Brace sweep
The sweep, or throw, is the diameter of the circle formed by the sweep handle when it is turned fully.
It is also double the distance between the centre line of the brace and the centre of sweep handle.
It is important to know the sweep size of a brace as the larger the sweep, the more torque you can apply. This makes drilling larger diameter holes easier.
However, the larger the sweep of a brace, the less likely it is that you will be able to make a complete turn of the sweep handle when working in confined areas. Braces with a smaller sweep can also be turned faster, so are better for driving in screws than braces with a larger sweep, as they are able to turn faster, they take less time to use.
The sweep size of braces starts at around 6″ (150mm) and goes up in 2″ (50mm) increments to around 14″ (355mm).
10″ (250mm) sweep braces are the most common size as they are the most versatile, being able to accomplish most tasks. Braces are generally sized in imperial measurements instead of metric as the metric system had yet to become widely used when braces became popular tools.
How are hand drills sized?
Like braces, hand drills have two sizes you need to be aware of.
Chuck capacity
The first size is their chuck’s capacity; this is the maximum diameter drill bit shank that the chuck can accommodate. The chuck capacity of hand drills is typically less than that of braces, with hand drill chuck sizes usually only going up to 8mm (5/16″) where as braces often have a chuck capacity of 13mm (1/2″) .
The reason for this is that a hand drill cannot apply as much torque as a brace, and so is unable to drill large diameter holes, unlike a brace.
Length
The other size you may need to be aware of with a hand drill is its length. This is the total length of the drill from the tip of the chuck to the end of the handle.
Hand drills that have a handle are normally between 230mm and 380mm (9″-15″) in length. On the other hand, hand drills fitted with a breast plate will typically be 355mm (14″) or longer.
Having a greater distance between your chest and the workpiece gives you more room to turn the drill’s handle, making the job easier.
What size hand drill or brace should you use?
Bit shank
The first thing you should do when selecting the size of a hand drill or brace is decide what size and shank shape bit you will be using, as this will determine the size and type of chuck the drill or brace must have.
Hole size and screw length
The next thing to consider is the size of the hole or length of the screw you wish to put into the workpiece.
For small diameter holes or short screws, a hand drill is better than a brace as it can be turned more quickly and can produce a greater cutting speed. Whereas, for large diameter holes or very long screws, more torque will be required so a brace is better suited.
Material and hole size
The next thing to take into account is the workpiece material. If the material is very hard, such as metal, then you will need a larger, heavier hand drill, as this will make applying pressure to the drill bit easier and less tiring.
When drilling a very hard material such as metal, if the hole you are looking to drill is greater than 6mm (1/4″) in diameter, you should consider using a large hand drill with a breast plate. However, for more delicate work, a smaller drill should be used to increase accuracy and prevent damaging the workpiece, even though this may mean the job takes slightly longer.
For large diameter holes in softer material such as wood, you are better off using a brace as you will be able to apply more torque to the bit. The larger the sweep of the brace, the more torque you will be able to apply, making drilling less tiring on your arms.
However, the larger the sweep of a brace, the slower the turning speed, so the longer it will take to complete the job.