Hurdy-gurdies can suffer from keys that fail to fall back properly - so-called sticky keys. This is usually due to changes in humidity and the unequal expansion of the wood of the key and the wood of the keybox through which the key passes. The key is deliberately a tight fit on the instrument, to ensure that it doesn’t wobble and that the tangent consistently touches the string in the correct place. However, this doesn’t leave much room for swelling in the damp. Here are some common solutions mentioned online:
- Just wait - when the humidity changes the instrument will be back to normal
- Using a very soft, graphite pencil, rub a small amount of pencil lead around the key where it passes through the keybox. This will lubricate the key and prevent it sticking.
- Apply some form of teflon lubricant to the key where it passes through the keybox. Various teflon sprays are available, or some luthiers (such as Neil Brook) sell a fluid comprising teflon suspended in an alcohol solution.
- Apply candle wax (known as paraffin in the US, but not UK) to lubricate the key
- Using a fine-grade sand paper, gently sand the key where it passes through the keybox. Don’t over do it!
Remember, if using any kind of lubricant on the key, keep it well away from the wheel!