How to Hack a McDonald's Happy Meal Minion Into an Electric Slide Whistle

How to Hack Phil McMinion:

Who doesn't love Minions from the movie Despicable Me? ...well when McDonalds recently had Minions as the prize in their Happy Meals, I had to make several trips to collect a few. One of the coolest looking of these little guys is Phil, he wields a bright red slide whistle. Problem is, the people who designed this either screwed up or more likely didn't want a bunch of angry, annoyed parents contacting McDonald's....because as a whistle Phil really blows! (...sorry, pun intended). It basically sounds like just air!?!

Well luckily our Maker Space the "Rabbit Hole" was having a Jameco Build Night with nifty parts we got from Jameco Electronics and Instructables. There were some 555 Timers Integrated Circuits I didn't know too much about...well with a little research I found 555 timers can be used to make all kinds of things including cool sound effects circuits. And I found this 555 Slider Synth circuit by Dean Segovis. It was perfect to fix Phil! (It's a fun circuit to build and play with, so if you don't have a Happy Meal Toy you can still build this project)

Because I'm working in a limited space, and for the fun of it, I decided to add an extra potentiometer to this circuit ...easier to adjust the sound generated. I also decided to use an external power supply plug instead of a 9V or even watch batteries...again because of the limited space.

Parts Needed for Slider Synth Phil McMinion

• 1 - Despicable Me 2 McDonald's Happy Meal Toy - Week 2 Phil
• 1 - 200 Ohm Potentiometer (optional)
• 2 - 100 Ohm Resistors
• 1 - Light Dependent Resistor (LDR) (Photo Cell)
• 1 - 2.2 uF Capacitor
• 1 - 100 uF Capacitor
• 1 - LED (different colors and brightness may perform differently, I had a small green one that fit in the tube great)
• 1 - LM555 8 pin Chip
• 1 - Small speaker
• 1 - Momentary push button switch
• 1 - 9 volt plug and adapter (or battery and adapter)
• 1 - Breadboard - (optional) I recommend building this circuit on breadboard first
• 1 - small chunk of perf board
• 1 - screw to hold the skull back on
• - Miscellaneous wire
• 1 - Aerosol can top (optional) - as an alternative to stuffing everything into poor Phil, you could just put all the battery and circuit into a stand of some kind and run wires from it up into Phil. Might give you more room

Tools Needed

• Magic three sided screwdriver to take apart the McDonald's Toy (Here is a good Instructable showing how you can make one of these)
• Small screwdrivers or pry tools for opening Phil
• Drill for cutting holes in Phil
• Soldering Iron and Solder
• Tape
• Heat wrap
• Dremel style tool (to cut hole for button, open whistle tube and to cut out interior support
• Glue - I used Maximum Strength Adhesive by Scotch 3M
• Hot Glue - I used a hot glue gun to hold the button and power adapter in place
• Screwdriver
• Scissors
• Small pliers
• Wire Strippers
• Xacto Knife

Here's a look at the finished McMinion in action:

Gather materials and tools and let's go!

(This Instructable submitted by the Rabbit-Hole Maker Space as part of the Instructables Sponsorship Program.)

Step 1: Create the Slider Synth Circuit on Breadboard

Prototype Phil on a Breadboard

Maybe you don't have a Phil, maybe you are waiting for him to arrive from ebay...well I recommend a breadboard first for this project anyway. Why? Well it's got some complexity, can be tweaked a bit and when it finally goes on perf board you want it small enough to fit inside the Minion...and besides....it's fun! Breadboard circuits are nice because there's no soldering, so they are quick, easy to debug and change around, etc. For this circuit you may want to play with different types of LED lights, different colors and different brightness cause different sounds.

Here's what my "breadboard synth" looked and sounded like:

You can build the circuit I'm providing here if you want the extra Potentiometer or use the original slider synth circuit ...or create a variation of your own.
Don't worry about using the tube for the breadboard version...you can make lots of fun noises even without the tubing.

Step 2: Crack Open Your Minion

Cracking open the Minion consisted of several steps:

1. Unscrew 1 bolt- you'll need the magic 3 sided screwdriver...even after unscrewing the bolt (never did get it all the way out) the Minion didn't want to open up...at first I thought the bolt wasn't unscrewed or the guy was glued shut, but it turned out he's held together by interlocking shells.
2. Pry open the edges - I had some plastic wedges obtained when I bought a replacement cellphone glass. Between these and some small screwdrivers, I found I could pry open the Minion until I could determine where the seam was on the top and pried that off
3. Pop the top - I found I didn't really need to fully open the Minion, I just pried off the top and had plenty of room to work.
4. Cut out the support post - the support post isn't really needed, so I used a dremmel tool to cut it out, being careful to not cut the bolt which was still in the middle of the post.
5. Open the whistle tube - there's a seam that connects the tube to the conical whistle section of the tube, but that is well glued together. I found it best to just dremmel off that section as shown.

Step 3: Graft on Some Stuff!

Graft on Some Stuff:

Button - A button or switch of some type is needed so you don't wear out the battery...In retrospect I might have put a toggle switch instead of a momentary switch...it would be easier to play with both the potentiometer and the slide whistle if you didn't have to hold the button down (then again if you have kids in the house, you may regret that decision :-) )   There was a spare momentary switch from a computer the night I was working on this, and after dremeling out an area for it....it fit nicely...some hot glue locked it in place.

Potentiometer - I couldn't find a small enough (cheap and handy) potentiometer to fit neatly in the Minion...my original thought was to use a wheel like an old school AM radio...but the one I found grafted nicely on the outside and left precious room for the rest of the components...This potentiometer has metal clips that hold it in place, so all I had to do is drill a couple of small holes for those, and then bend the clips over on the inside...nice.

Power adapter - I could have made watch batteries fit inside the Minion, but they cost more, wear out faster and replacing them would be a chore...so once again I just dremeled out a square and hot glued the adapter in place.

Solar/Photo Cell/Led - I used a small piece of foam to allow the cell to fit snugly in place, ran the wires out the end you would normally blow into.  I drilled 2 small holes for the led bulb and mounted it on the end of the red slide whistle ...once I knew the circuits were good, I glued the whistle shut again. 

Step 4: Move the Slider Synth Circuit to Perf Board

Move the Circuit to Perforated Board

I needed a review on perf board tips especially since this circuit had to be small enough to fit into the Minion
I found this video had some pretty good perfboard tips. 

I found it was useful to work a piece at a time...I mounted the button, LED and the PhotoCell in the Minion and made sure the breadboard circuit still worked...then moved the POT, tested it...until it came time to move the internals.

As you can see from the image I used breadboard wires to connect the perfboard....probably not recommended but they worked well for me.  I also left little postit notes to myself reminding me where things go after the move from bread to perf.

Step 5: Let's Put the Lid on This Thing

Let's Put the Lid on this Thing

Well after getting the perfboard version of this guy working, I had to jam the board and wire into his tiny minion body.
Man it was tight...I had to cut off the edges of the perfboard...shorten some of the wiring, and fold up the wiring...just barely fit!...and still worked !

Next to put the top back on....I had to cut the tabs off the hair and skull pieces...but I didn't want to glue things shut...so there was just enough room to fit a big Frankenstein style screw on the top of his head and down the left hand side...worked fine and I can still get back in if I need to.

Thanks for checking this Instructable out....Good Luck with all your Projects!