Finger Locking

For small cracks.
The hand is inserted into the empty crack, with the thumb pointing down.
The hand is twisted, clockwise for the right hand, anti clockwise for the left hand.

This has a 'camming' effect and locks the fingers into place - you can relax the muscles now and the hand will stay put.

• Sometimes two or three fingers works better than all four.
• Overlapping your fingers slightly to stack them up often helps, so that your forefinger is slightly on top of your index finger and your ring finger is slightly on top of your forefinger. The effect is to combine your fingers into a more solid unit. This is known as a ring lock.
• The thumb can squeeze the outside of the crack (see diagram), but it is often useful to either press the thumb pad against the index finger pad or (more often) to tuck the thumb underneath the index- and forefingers.
• An alternate finger jam can sometimes be formed where there is a constriction in the crack. Place two fingers above the constriction and your thumb below squeeze the index finger and thumb towards each other so as to form an "O" as if you were signing "OK" to someone. The constriction of the crack can be trapped in the "O" this way.