Cup Rotator Download FIles

A little while back I created a cup rotator for applying resin evenly to travel mugs.  I posted a bit of an amateurish video to Youtube, and someone asked me if the files were available.
I never intended making the files public, but don’t want to be selfish and deny people who are interested the opportunity to build one themselves. 

So, here are the STL files.  They are actually an upgrade to the version shown in the picture to allow the driver board to sit within the tower, and an enlarged foot for better stability. (I’ll get a picture of the new version uploaded). 

To make the rotator I used:

5v Stepper motor with ULN2003 Driver board


Cut down 10mm Bamboo knitting needle

‘Magic Sponge’

4 Mounting screws


Print the 3 STL files and glue the tower into the base. There is a small arrow on the bottom of the tower which points forward.

Load the program below into the Arduino.

Insert the motor into the top section and secure with two small screws. The top has a slot to make manipulation of the wires easier.

The tower is made to accommodate the ULN2003 board within the body. Connect the motor wire, 4 control wires and 2 power wires and insert the board into its recess.

Connect the wires to the Ardiuno (for the code below I used the pins 4,5,6,7 and hot glued them into position.  I also power the motor directly from the board – I know, it’s not usually recommended, but as the motor runs so slowly I figured it would be ok and it hasn’t let me down yet.  Use an external power supply if preferred.
Feeding the control wires over the top and the power wires around to the right, screw the Arduino onto the mounting holes in the base.

Glue the adapter onto the motor spindle and glue your rod into it.

Cut a hole for the rod into the magic sponge and insert it onto the rod.

That’s it! Power up and have fun!

Arduino code and files

#include <Stepper.h>

#define STEPS 2038 // the number of steps in one revolution of your motor (28BYJ-48)

Stepper stepper(STEPS, 4,6,5,7);

void setup() {
// put your setup code here, to run once:

//nothing to do


void loop() {
// put your main code here, to run repeatedly:

stepper.setSpeed(1); // rpm

stepper.step(2038); // do 2038 steps — corresponds to one revolution



These files are provided for educational purposes only and I offer no warranty either expressed or implied.
It is your responsibility to check any files and hardware before use, and usage of the files and code is your agreement that I will not be held accountable or responsible for any loss or damage howsoever caused.

Apologies, but I am unable to offer any kind of technical support in relation to this project.