How to use an Allen key

• Allen key of the right size (supplied, or a metric set)
• Optional: a hex bit for a screwdriver handle

Before you start, lay everything out on a soft surface (the flattened box works) and check it against the parts list in your manual.

• The bolt or screw you are turning
• Its washer, if the manual shows one

1. 1

   Step 1: Check the size: the key should slide fully into the hex socket with almost no play. A loose fit will round the socket.

2. 2

   Step 2: Push the key all the way into the socket, not just the tip.

3. 3

   Step 3: For speed while the bolt is loose, hold the long arm and turn the short end in the bolt, spinning it quickly with little force.

4. 4

   Step 4: To tighten, flip the key: put the short end in the bolt and turn the long arm. The longer lever gives much more force.

5. 5

   Step 5: Turn clockwise to tighten and anticlockwise to loosen (unless the manual shows a reverse thread, such as a bike's left pedal).

6. 6

   Step 6: Tighten until the bolt is firm and the parts are pulled together, then stop. Flat-pack fittings need firm, not maximum, force.

• Using an imperial key in a metric bolt (or the other way round), which fits loosely and strips the socket.
• Only putting the tip of the key in the socket.
• Fully tightening each bolt as you go, before the frame is square.