This post tells you how to unwind a carriage clock. The same method can be applied to almost all other mechanical clocks. If its a big clock and you are not confident then get somebody quite strong and mechanically minded to do this for you. This might seem extreme but there is a lot more power in a spring than you think and its easy to get caught out and injure yourself with twisted or broken fingers.
Before anything else, PUT YOUR PROTECTIVE EYE WEAR ON. If you dont have any go and get some. It really isn’t worth proceeding from this point onwards without it. The risk is high quite frankly and I was stupid enough to have a couple of close calls before I got the message. Don’t do the same as you might not be as lucky.
To unwind the clock you will obviously need the key. If you don’t have a key don’t unwind the clock or go any further until you have a key that fits.
The reason for this is that you need to hold on to the key while you release the ratchet that holds it against its spring pressure. When you do this, if you don’t have a firm hold on it, you might find it spins out of your hands or even get thrown off its spigot towards your well protected eyes (clever you with your protective eye wear on!).
Sorry to go on about this but the risk is high compared to other things that you would normally wear protectives for.
Have a good look at the picture below and hold onto that key before you release the ratchet. Once you have released the ratchet you will feel the pressure of the spring through the key you are holding.
Unwind the carriage clock in half turns and release / apply the ratchet between the turns so that the spring pressure is always managed by either your fingers with a firm hold on the key, or by the ratchet being allowed to stop the backward movement.
IF YOU RELEASE THE KEY WHILE THE RATCHET IS OFF THE CLOCK MAY SLIP ITS MAINSPRING. So…make sure you have the key under control at all times when the ratchet is off.