Mortal Kombat II - *Desktop Arcade* With Retropie

Intro

Okay so a couple years ago I made a full size 2 player arcade for my garden shed/gym. https://www.instructables.com/id/Street-Fighter-II...

Now I want something small for my computer desk, inside the house. So I started deconstructing designs.. Loads of people have modded an "icade" which was designed for the ipad. But this model is alot bigger then I wanted. My arcade can also be powered by a power bank unlike other machines.

It took me a while to create a perfectly scaled Arcade machine, small enough to move around but compact and sturdy enough to play a wild game of Mortal Kombat "G3t oVer HeRe". I had to keep remeasuring and testing as I wanted professional full sized arcade/joystick buttons.

Enjoy :)

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Things you Need:

Raspberry Pi 2 or 3 = £30 - https://thepihut.com/products/raspberry-pi-3-model...

64GB SD Card = £10 - https://www.amazon.co.uk/SanDisk-Ultra-microSDXC-C...

Mini USB Burger Speaker= £5 - https://www.ebay.co.uk/itm/Black-Mini-Portable-Tra...

Volume Adjuster= £3 - https://www.ebay.co.uk/itm/3-5mm-Earphone-in-Line-...

7" Inch TFT Screen= £25 - https://www.ebay.co.uk/itm/7-inch-LCD-TFT-Display-...

Zero Delay= £10 -1 Player Control Arcade Encoder with USB Cable & Wiring Kit -https://www.ebay.co.uk/itm/Zero-Delay-CY-822D-1-Pl...

30cm HDMI Cable = £3 - https://www.ebay.co.uk/itm/30cm-1-Foot-short-HDMI-...

12V 4 Pin 12mm LED Metal Push Button Momentary Power Switch Waterproof =£3 - https://www.ebay.co.uk/itm/12V-4-Pin-12mm-LED-Meta...

Left Angle Micro USB Male to Female extension cable=£3 https://www.ebay.co.uk/itm/25cm-Left-Angle-Micro-5...

Black Momentary Round Push Button Switch = £2 https://www.ebay.co.uk/itm/Red-or-Black-Momentary-...

50cm LED Light Strip for Marquee Light - £2 https://www.ebay.co.uk/itm/5050-USB-LED-Strip-TV-B...

USB Switch for Marquee Light - £2 https://www.ebay.co.uk/itm/USB-Cable-ON-OFF-Switch...

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From Arcadeworld

Purple Half Inch (12.5mm) T-Molding (11 Feet) £10 -- https://www.arcadeworlduk.com/products/purple-hal...

Joystick & Buttons

Zippyy Short Shaft Ball Top Arcade Joystick1 (Yellow) £12 - https://www.arcadeworlduk.com/products/Short-Shaft...

Gold Leaf Concave Arcade Button- £18 (X4 Yellow, X 3 White) - https://www.arcadeworlduk.com/products/Gold-Leaf-A...

Start Player Button = £2 -https://www.arcadeworlduk.com/products/Classic-Arc...

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Wood 5.5mm Plywood £13 - https://www.wickes.co.uk/Wickes-Non-Structural-Har...

Graphics £10 - If Printed professionally...(I used my own printer.)

2mm Clear Acrylic Sheet (600mm X 1220mm) £20 - https://www.wickes.co.uk/Wickes-Durable-Acrylic-Cl...

Total = £180 - You can do this for cheaper if you use different joystick/button. I choose good quality and a recognized brand but there are alternatives out there...

Prep Work

Print Template Pages attached. I have included a cutsheet.. To show how this can all been done using a small sheet of 5.5mm thick (606x1220) PlyWood... Don't use MDF its not as strong.

You will need an A3 printer to print the side panel or you could use A4 and tape the paper together them together.

Link to templates also available here..https://www.sendspace.com/file/do35bg

Everything comes out of a 606mmx 1220mm 5.5mm sheet of Plywood.

Once you have all your pieces.

The Screen
Cut out the holes and notches same as the template. Dont worry about the screen1 hole (frame) being cut perfect just make sure the 7inch tft will pass through it. As you can see from my pic I used a coping saw and its not perfect.

Line up the second screen wood piece and thread the screen cable/wire through the notch.. Glue the screen using super glue or similar. Don't use your hot glue gun for this as you don't want the screen to melt.

Once you have threaded the TFT cable through the hole attach it to the TFT Circuit Board. you will need to glue the circuit board to the back of Wood Piece 2 just like in my pictures. Make sure you use a spacer of some kind to stop the bottom of the circuit board touching the wood piece. (for air flow and to prevent components being affected).

The button Panel is made from 2 pieces of wood stuck together. (5.5mm + 5.5mm) thick to give the board more strength.

Drill 28/29 mm holes into the panel for the buttons to fit. You will need to measure and cut out the joystick bottom.

To do this remove the top plate and measure around the bottom to see how much needs to be cut out in order for the joystick to fit through.

There are lines on the template of how the joy stick should sit. You will need a router or chisel to remove 2-3mm from the top layer so the plate sits flush with the panel.

This is made from a single piece it doesn't need two layers. Drill 2 holes.

Each side is made from 2 pieces of wood. DON'T STICK TOGETHER! at this stage. Just clamp together.

It is quicker to clamp 2 at a time then cut around the template provided. I did this manually with a straight saw and coping saw for the edges. Sand down to get the edges smooth.

You should end up with 4 of the same pieces.

I ripped a 2-3 mm thick box apart and glued like in the pictures to make separators.. Wood or plastic separators could be used as an alternative. I used the box my 7inch TFT came in. Do this once for the left side and once for the right side. Once completed glue together, 2 for each side.

We do this so the T-Trim will fit around the edges.

I used a hot glue gun to get this done quickly.

Cut the additional Pieces out this includes:

Top piece

Back piece

Bottom Piece

Speaker Piece (This holds up the Marquee)-Drill the speaker holes just as they are in the template. You can make them as big or small as you want.

Glue the arcade together. Use the lines from the template side panel for guidance.

Make sure the Joystick has been tested before gluing it in place.

I used Assembly Joint Blocks like this to attach everything.- https://www.screwfix.com/p/white-assembly-joint-x-...

As the panels are thin and I didn't want to risk cracking I used a hot glue gun and melted glue to stick these together. Wood glue would be fine but it takes a while to dry so I used a hot glue gun.

Okay..

Step 1 - Setting Up Pie

So get a Raspberry pi 2 or 3. A Pi 3 is preferable as it is more powerful and has more features.

You need a 32GB...64GB or 128GB Micro SD Card.

Download a Retropie Image you want from here... https://www.arcadepunks.com/retro-pi-downloads-pag...

An image is a single file with everything preset and ready to go. Depending what games and interface you want there are different choices... I downloaded RETROPIE INFINITY 64GB as it has a wide range of console emulators. (OVER 15,000 games)

OBVIOUSLY don't get an image bigger than your MicroSD Card as it won't fit.

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Once you have downloaded the image to your computer, also download Win32 Disk Imager.. you can get that from here...https://sourceforge.net/projects/win32diskimager/

We use Win32 disk Imager to put the Infinity Image onto the MicroSD Card. Tutorial how to do this here....

Safely remove the MicroSD and put into the pie. Start up and check everything is working. Use USB keyboard to navigate.. Then shut down using keyboard. It will be what ever you have set the start button as then power down. IMPORTANT--- Treat the Pi like a computer.... safely power down or you corrupt file and the control board. (don't just unplug the power!!)

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Step 2- Programming the Off Button

Setting an off button so you don't need to navigate to the shutdown screen every time.

Silly but yes this is not a default thing in Raspberry Pi.

I didn't bother with the light so just connect a Momentary Button to GPIO22 & 3V3 (Pin 15 & 17) on the Raspberry Pi Circuit board.

Here is the tutorial on how to do it.. . https://www.raspberrypi-spy.co.uk/2018/03/raspberr...

Easiest Way is Method 2.. Remotely scripting from your PC.. Pluging Ethernet cable into your pie direct from your router) When I say scripting I mean copy and pasting..Its all explained in that tutorial.

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Step 3- Changing the Splash-screen

You can modify your splash screen to be the same as mine - MKII Purple Edition. Download available below.

You can add this video using this tutorial.. https://github.com/RetroPie/RetroPie-Setup/wiki/Tr...

Glue Plastic Blocks for where the back and bottom will be resting so you know where to glue things around.

RapsberryPi

Start off by gluing the Rapberry Pi above the screen circuit board. I used a combination of blocks and spacers to keep the pi away from the wood to prevent overheating and components/solder touching the wood.

The Raspberry PI powers via its USB ports the Arcade Delay encoder and the USB Speaker only.

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7Inch TFT Control Board- (To change source/power/brightness/contrast)

Mount this to the left side (if looking from the back) Same as in the pictures.

Speaker

Glue to the left side.. Make sure you can access the on/off button just in case you need to turn it off. The speaker connects to the the volume control wire.

Volume control

This is where I got smart with a basic design, hot glue gun the volume controller to the block.. Make sure it sits out a bit from the plastic block so it is reachable through the back panel. (same as picture) The Volume controller connects to the Speaker and the Raspberry Pi.

USB Hub

Do the same with the USB Hub, glue it so it sits on the plastic block reachable from the outside. Put this on the right side.

The USB Hub powers the Raspberry Pi, 7 Inch TFT Screen & the Marquee LED Light strip.

(Use the Left Angle Micro USB Male to Female extension cable) to power from the hub to the Raspberry Pi)

LED USB Light Switch

Again Glue the switch to the plastic block. This one should be on the right side just as it is in my pictures.

TIP---- If your using a hot glue gun you can glue the cable ties or the wire twists to keep the wires secure. Be careful not to hot glue gun wires directly as you can melt the wires and stop them working. Also its easier to cut cable ties if you make a mistake.

Connect the USB switch to the LED light strip, so you can choose if the lights are on or off. Its easy to attach the light strip as these have peal off sticky backs. Position the strip on the inside of the marquee just like in the last picture.

You will find everything fits but it is tight. You may need to slightly bend the micro-switch pins to be able to fit the wires on.. If you do have to bend the ends make sure the wire ends don't touch. If they do..use insulation tape to wrap around the ends to stop pins conducting each other.

Arcade Encoder

Mount/Glue the Zero Delay USB Encoder to the left hand side. Use a spacer to prevent the circuit board directly touching the wood. The red and black wires only fit in the Zero Delay encoder board one way. And the gold leaf (silent buttons) can be connecting any way positive to negative.

But when you connect the start button (mirror Switch) and joystick... The negative (black wire) goes the outside terminal (Com/Common) and the positive (red wire) connects to the middle terminal (NO Normally Open) on the microswitch. Same as picture

If you have smaller wire connectors and they need to go on a bigger connector you can use a flat head screwdriver and bend the ends out a bit to fit.

Get Printing

Print the graphics on an A3 printer. I used Matte Card because that's what I had in my house.. It would be better to get these done professionally for cheap from freeprintsapp.co.uk or a website like that. Because photo quality like the ones you get have a special protective layer on top which will give your graphics/colour longevity.

I used spray adhesive/glue to stick these evenly across the wood. With the Screen, Marquee & Button graphics I didn't stick with glue just used the protective clear acrylic to keep flat.

TIP: When you cut the frame for the black outer screen border use a scalpel. But more importantly you will get white edging where you have cut the centre out. Go over the edges with a black marker to colour this black.

To make this look professional you need to add the plastic casing on the button panel and marquee.

Button Panel Clear Acrylic

To create the button panel print off the template again for this drill the holes so they line up with your existing panel. You will need to print the graphics and place this on the wood before securing the plastic. I found I only needed one screw on the left hand side to secure the plastic panel down. The other side was held tight by the button secure rings.

Marquee Clear Acrylic

Cut 2x pieces of 2mm Clear acrylic 220mm x 65mm. Once you have the Marquee printed cut the card design the same size and sandwich it between the 2 pieces of Acrylic.I used superglue/resin and put a little bit around the edges to keep the pieces together. NOTE: A hot glue gun would not work as it is too thick.

Stick using superglue/resin. Only use a little bit...You don't want to use a glue gun because when it lights up you will see the thick glue line around the edge. This should fit nicely.

Screen Clear Acrylic

Cut a piece 220mm x180mm same as the screen panels. Line up black border frame and place arcylic ontop. A little superglue around the edging to keep in place.

T- Trim..Glue the t-Trim into the groove around the side panels. Start from the bottom corner at the back and work your way around the side panel towards the front and finish by ending with the straight run at the back. I used the hot glue gun for this. Its best to do small bits at a time allowing it to dry/stick before moving on. You will need to cut the back of the t-Trim when there are curves/corners otherwise it will not fold in on itself properly.

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Secure the bottom panel with a single screw. You will find the pieces jam together nicely so it doesn't take much to secure in place. The single screw can go through the bottom into one of the plastic blocks you have already glued.

I planned to screw the back in place but because of the nice tight fit I just pushed the back in place. Remember to cut the 4 holes. For volume control, power button, the Hub (Power Input) & marquee light switch.

Your Done...

Excellent...Flawless Victory!!!! (^_^)