Hello! This is a tutorial about how to make a half-automated percussion instrument in the shape of a doll.

The actual percussive material of this rattle-doll is walnut shells because of their soft and gentle, very charming sound in combination with sea shells which are adding some nice highs into the mix. This specific doll-rattle is therefore called “Mrs Nutshell”. You can use the rattle in both, acoustic or motorised mode. Thus Mrs Nutshell in spite of her inert appearance is a versatile musician and enjoys participating in noise-concerts because of her stunning eyes and drony motor-sounds. Nevertheless she wouldn’t refuse any appearance in other experimental acoustical environments either. But one is for sure, she likes to get her solo (and also going for a walk on Sunday afternoons).

Supplies

Materials

Puppet (any)
Walnuts Shells
Sea shells
Vibrating DC motors (2)
SPST On-Off switch
Battery holder for AAA-batteries (4)
300 ohm resistor
3mm LED
Thread
Wool
Super glue
Cable tie

Tools needed

Drill (3mm, 2mm)
Solder iron (+ tin etc.)
Small plier
Needle
Crochet needle

Step 1: Electronics

The electronics (motors and LEDs) have to be fixed inside of the doll. Therefore you have to undo the head of the doll (and maybe other parts, depending on your doll). Make sure while choosing your doll that this can be done easily - in Mrs Nutshells’ case the head was simply attached with a cable tie inside the fabric of the neck which made detaching and rebuilding quite easy.

Before putting the several elements inside the doll you should solder them to the power supply. https://www.wikihow.com/Solder

The battery enclosure has two wires (ground and positive) and a built in switch. Connect positive to the one leg of the first motor and also connect the register in parallel. The other leg of the resistor is in parallel to the second motor and both the LED’s. Remember the positive wire will connect to the long leg of the led. The short leg of the LED and the other leg of the second motor connects together with the ground wire.

(PS: A better version of Mrs Nutshell would be: instead of a switch put a potentiometer in order to be able to change the speed of the vibrations...And I know this is not very sophisticated way to connect the LED and motor. But it was Christmas and we were salvaging what ever was available in the garage and other old electronic stuff. The LED and the motor needed some sort of current limiting - could salvage only one resistor ;))

To fix the LEDs you have to drill holes the size of the LEDs into the eyes of the doll. Also choose a place where you want to put the switch for the second motor and drill a hole the size of the switch. The LEDs can be fixed permanently with some superglue, the switch can be fixed with the screw nut that comes with it (in most of the cases...).

One motor has then to be placed inside the body and the other one inside or on top of the head of the doll (depending on accessibility). In both cases the motors are fixed with cable ties (inside the body with a cable tie all around the waist of the doll to make it shake more. To fix the motor inside or on top of the head, drill two holes into the head and use two cable ties to pull the motor as tight as possible.

Step 2: Design

The percussive elements of your doll need to be pierced in order to fix them on body and hair. To pierce the nutshells and shells we used a 2mm drilling bit (drill slowly and carefully otherwise you’ll break the shells).

Next step needs calm and patience: stitch the shells to the puppets body (make sure that the thread is of good quality) and tie the nutshells to the hair of the doll (we used the hair itself - in order to make the knots stable we used superglue on top - you might want to use a crochet needle or a normal needle to tie knots and put the hair through the holes). All elements should overlap a bit in order to produce sound when they are shaken.

The battery pack is fixed on the back of the doll in a small handmade backpack out of crochet (https://www.wikihow.life/Crochet).