Abstract: A method of adjusting the effective thickness and/or shape of the neck of a string instrument involves use of spacer device consisting of a precisely molded or shaped material such as wood, metal, or plastic that covers the palm of the hand between the thumb and index finger including the web, thenar compartment, central compartment and hypothenar compartment as well as distal and proximal palmer area used to precisely thicken and modify the shape of the neck of a stringed musical instrument. The spacer device may be bonded to a holder such as the palm area of a fingerless glove or to a strap device covering the palm of the hand using hook and loop bonding material or an adhesive. Alternatively the device may be directly attached to the neck of the instrument or attached to the palm of the hand or held in place by the pressure of the palm on the neck of the instrument. The wooden spacer has a low enough coefficient of friction to slide freely along the neck of a string instrument.