How do I clean and look after a cordless drill?

Cordless drills fail for a small number of reasons, and dust is behind most of them. It packs into the motor and stops it cooling, it grinds in the chuck mechanism, and it insulates the battery contacts. None of that needs a workshop to prevent, and the routine takes less time than finding the tool in the first place.

Safety

What you'll need

• Compressed air, a puffer or a soft brush
• Dry lint-free cloth
• Light machine oil (optional)
• Grease, for SDS tools (optional)

Step by step

1. Take the battery out.Before anything else, every time. It also stops the trigger being pressed accidentally while your fingers are near the chuck.
2. Blow the vents clear.Air in through one set of vents and out through the other, so the dust travels the way the cooling air normally does. Blocked vents are the commonest cause of a motor cooking itself.
3. Clean the chuck.Open the jaws fully, blow the dust out of the guideways, and work the sleeve back and forth. Masonry dust in a chuck is what makes it jam and what wears the jaws.
4. Oil the chuck mechanism sparingly.A single drop into the jaw slots, worked in by opening and closing, then wipe everything visible. Oil on the jaw faces makes bits slip, which is worse than a dry chuck.
5. Wipe the battery terminals.Dry cloth on both the pack and the tool. No abrasives, no liquid. Dirty contacts cause intermittent running that people mistake for a failing tool.
6. Check the trigger and the switches.Work the trigger through its travel, the gear selector and the forward-reverse. Grit in a switch is a common failure and blowing it out early prevents it.
7. Grease SDS shanks and holders.If it is an SDS tool, a smear of grease on the bit shanks and a clean holder is the maintenance that matters most, and it is the one nobody does.
8. Check the lead on corded tools.Flex the whole length, check the strain reliefs at both ends and look for damage near the plug. A damaged lead is the most common genuinely dangerous fault on an old tool.
9. Store it dry and out of the cold.In its case, with the battery removed and stored indoors at around half charge. A drill in a damp shed corrodes at the chuck and the contacts long before the motor gives up.

Tips

• A cheap hand puffer or a bicycle pump does most of what compressed air does and lives in the toolbox. The point is doing it, not the equipment.
• Do not use compressed air to blow dust off yourself or a workmate. It drives particles into skin and eyes and can cause serious injury.
• If the tool is noticeably hotter than it used to be for the same work, the vents are blocked or the bearings are dry. Both are worth attention before the motor fails.

Keeping on top of it

• Blow out vents and chuck (after any dusty job)
• Wipe battery and tool terminals (monthly in regular use)
• Drop of oil in the chuck mechanism (every few months)
• Grease SDS shanks (every few uses)
• Inspect lead, plug and case for damage (before each session on a corded tool)

Questions people ask