Timed Release Copyright 2010 schmerzbold

 

How this works:

1) The ice melts and lets the weight fall down.
2) The weight will pull the bolt out freeing the ring between the two bails.
3) You can move your hands to get the key for the handcuffs.

 

Always use at least two completely different release methods, preferably more to be safe if one of them fail. Always play safe!