A WORD OF WARNING/DISCLAIMER: If you decide to try to build a diddley bow of any sort, be aware that the wire may be of unknown tensile strength and is being brought to unknown tension; in addition, if you use a glass jar or bottle as a bridge , remember it is under compression, and the board being used is under tension. I suggest using safety goggles and gloves when bringing the wire string to tension. I have had a glass baby food jar bridge shatter as I was attempting to bring the wire to a higher tension. Glass flew everywhere. Be careful to keep your face out of the way of the wire—I do not know what would happen if the wire should break (it has not happened to me—so far) but please use sense when building, tuning and playing these instruments.
