What to Look at When Purchasing a Cordless Drill
Voltages for cordless drill batteries range between 4.8v to 30v.
The DIY range is typically between 12v to 18v
The batteries used in cordless powertools are rechargeable with the 3 main types being the following,
NiCad's are the most common type of battery used in DIY models.
- NiCad (Nickel Cadmium)
- NiMH (Nickel Metal Hydride)
- Li-Ion (Lithium Ion)
NiMH are found on some premium trade models.
Li-Ion are found in cordless screwdrivers
The Amperage rating of the battery refers to the amount of current it can supply . This ranges from 1.2 amps to 2.5 amps, the larger the amps reflects Longer run time.
Battery Charge Times
Chargers for cordless drills are rated in how long they take to fully charge a discharged battery. This ranges from 10min to 5hrs. The two most common charge times are 3hr and 1hr.
DIY cordless charging time = 1 -5 hours
Professional cordless charging time = 10 minutes to 1 hour
Cordless Drill – Run Time Factors
(How many holes will I get from my cordless drill)
This is a question that has many variables and is difficult to give a precise answer, some of the factors that can effect the performance or number of holes you get per charge are:
Temperature – outside temperature & battery temperature
Material being drilled into – harder material less holes
Feed Rate – push harder on tool – less holes
Life/Quality of Accessory – dull or poor quality accessory – less holes
Size of hole – larger the hole – less holes
User bias – different users = different techniques = variation in outcome
Chuck Size & Type
10mm (⅜") or 13mm (") are most common sizes of chucks, this relates to the largest size full shank drill bits it can accommodate. Chucks are either keyless or keyed, most cordless drill come with keyless chucks. Keyless chucks offer faster accessory changes which increases productivity.
Single, two speed and variable speed is available with variable speed most common.
Clutch / Torque Settings
Used to auto stop the rotation of the chuck at a pre-determined torque setting, this is primarily for fastening applications.
Some Professional cordless drills have hammer action, this enables the user to drill holes in concrete & masonry.