Taking the Coin out of "Coin Operated"

A few years ago the company I worked for also had their hands in apartment rentals. In trying to improve their facility they purchased at auction a truckload of brand new commercial coin operated washers & dryers intended for a bankrupt laundromat. Fortunately for me the units were never used and still had the original wrapping on them. Having picked up more then they needed at a good price I was offered for free a new washer & dryer for my home as opposed to buying a new set costing me an upwards of $400 & up. The only downside to the units were the fact that they were coin operated which wasn't to much of an issue as I had the coin tray key so I could use the same 5 quarters for both the washer and dryer.

While the system of using the same coins worked well for a number of years after some time it just became tiresome. Having no luck finding answers online I asked my father an engineer with over 30 yrs experience in the field of Industrial Operations how to remove the coin aspect of the units his response was one of "Don't do it!!, the machine won't work correctly." Trusting my father as all kids do no matter how old they get I left it alone until a few weekends ago thanks to the tooth fairy needing to borrow some coins from me I was stuck in a situation where I couldn't do my laundry due to not having $1.50 in quarters and every time myself or my wife would go out somewhere we would forget to get quarters once again I needed to find a better solution.

While I did have the key to the coin box I was missing the more important key that unlocks the compartment where the machine timers and start leaver are located. Taking a drill and a 3/8 drill bit I proceeded to drill out the lock to grant me access to the control compartment.

After opening the lid and getting a better look at the control mechanism I already noticed that to spite what I had been told previously this was going to be an easy "hack" in a manner of speaking.

For those who don't know the inside of a coin laundry machine, when the coin tray is pressed in all the way a arm pushes the timer spring loaded lever back and allows the tray to move the timer forward engaging the machine. Simply removing the coin part would allow me to do the same function with out the need for the coins.

Looking inside I noticed the only thing holding the coin mechanism in place was 4 #2 Phillips machine head screws and a long threaded bolt. After loosening the timer I removed it from the machine to give me more working space, as you can see you don't have a lot of room to work with.

After removing the plastic coin guide that allows the coins to fall into the coin tray I proceed to remove the screws and the 1 bolt.

On the bottom of the coin tray past the cover are arms like levers that allow the coin tray to fully engage the timer as long as there are quarters in the tray other wise it stops dead as it should when trying to move the tray forward.

Removing the pin that holds the arms in place allowed me to remove the arms and allowing the coin tray to engage the timer fully without the need for coins as you can see from the short clip below

The same type of system holds true for the dryer with regards to the coin tray removal and arm's that allow movement when the coins are in place. The only big difference between the two units other then one is on the right side & the other is on the left is that the timers are different as you can see from the video below.

The purpose of putting this little short blog post out there was to help those who may be in the same situation that I was in, as you would be surprised the number of well maintained laundry equipment that you can find for sale under $50, but unfortunately are over looked due to the Coin aspect.

Arduino Based Book Report Diorama

     My 10yr old daughter recently had to do a diorama for a school book report as a presentation. Seeing examples of diorama's from museums, libraries and other kids projects at school she asked if we could make it cool. Asking her what she meant by "make it cool" she asked if we could add lights or moving parts to it, in which I was more then glad to accommodate as it would be a great way to introduce her to micro controllers and earn her another badge for the Adafruit "Hack Scouts".

In wanting her to learn just what micro controllers are used for I lent her my copy of "Getting Stared with Arduino" which even though is a little technical for younger readers just getting started, was a great reference tool to show her just a few examples of what people can do with an Arduino and explain the coding involved within Arduino.


Her design (as seen below) called for some simple things that were easy to accomplish with the Arduino platform. She wanted to have a yellow glowing light shining from inside the dresser drawer as described in the book, a light on the ceiling in the boys room, the boy, a bed, and a dresser.


Originally when helping her plan things out she wanted to have the dresser drawer open & close but unfortunately due to time & cost restraints we had to skip that moving part of the diorama and leave it fully open with just the LED's lighting up.

Taking a trip to our local Radio Shack we picked up a Servo motor, a 10mm white LED, & 2 yellow 3mm LED's for less then $20. Starting work on her project on April 22nd Earth Day I thought it would also be good to incorporate the use of recycled materials from parts & wire we already had here at the house from our parts pile which usually consists of broken computers, printers, scanners, etc.

To prevent any trips to the hospital I cut and shaped out the wooden box for the diorama along with the dresser, & bed. She picked the colors she wanted to paint things and we got to work on the projects appearance. Next we positioned everything were it needed to be along with hot gluing down things like the dresser, bed & LED's in their respective locations.

 After all the eye candy was done we went to work on the back of the box where the wires and everything else would be housed at. Already working towards earning her multimetter skill badge we talked about the importance of wiring and why Ohms law was so important when dealing with electronics, though while she didn't grasp all parts of Ohm's law she knows with out the use of a resistor in certain parts of electronic you might damage the micro controller.

When it came time to make the Ardunio work it's magic we used the "Sweep" example by BARRAGAN found within the Arudino example library and modified it to match our specifications as well as add the function to turn on the LED's.

// Sweep
// by BARRAGAN <http://barraganstudio.com>
// This example code is in the public domain.


#include <Servo.h>

Servo myservo;   // create servo object to control a servo
                            // a maximum of eight servo objects can be created

int pos = 0;          // variable to store the servo position

void setup()
{
 pinMode(13, OUTPUT);    
  pinMode(12, OUTPUT);

  myservo.attach(7);  // attaches the servo on pin 7 to the servo object
}


void loop() {
 digitalWrite(13, HIGH);   // turn on the LED
  digitalWrite(12, HIGH);   //turn on the LED
 
  for(pos = 0; pos < 40; pos += 1)    // goes from 0 degrees to 40 degrees
  {                                                     // in steps of 1 degree
    myservo.write(pos);                     // tell servo to go to position in variable 'pos'
    delay(15);                                     // waits 15ms for the servo to reach the position
  }
  for(pos = 40; pos>=1; pos-=1)       // goes from 40 degrees to 0 degrees
  {                               
    myservo.write(pos);                     // tell servo to go to position in variable 'pos'
    delay(15);                                     // waits 15ms for the servo to reach the position
  }
}

The video below is my 10yr old daughter showing off her project and giving a "shout out" to the open source hardware community.

While we won't know her final grade until next week, she has told me after the comments from YouTube, Twitter & seeing her project appear on the Adafruit blog , she knows it's an A+.

On a side note a very big THANK YOU to everyone who has left comments on her project. A very big thank you to the Arduino community & to Adafruit for their idea of "Hack Scouts" and everyone else doing work with the Open Source Hardware Community.