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Part 5: final assembly Phil Prosser’s Phenomenal B y now, you should be familiar with the deck, the various parts and the software. We are not going to try to give full constructional details, as they would be very long and complicated. You should be able to figure the rest out with a bit of guidance. We expect you will make your own layout, taking your own approach to the deck and its decoration. Our play surface is 470mm wide. If you are keeping to this, you can use our entire lower section unchanged. You can either copy our middle and upper play area or make your own from scratch, or based on ours. The CAD files on our website can be used as a starting point to make your own deck parts (www.siliconchip.com.au/ Shop/6/3628). Our Machine is shown in Photo 1. This final article will therefore touch on the following: Finishing the deck off Assembly of the ‘back box’ with the controller, power supply, speakers and scoring Final installation of the electromechanical parts on the deck Wiring Decoration Testing We will provide a few pointers on the software in this article, which should set you on the path of being able to change lights, interactions of switches and rollovers to scoring, lights and high current outputs and also sounds. This requires some programming skills but the code is not terribly complicated. 📍 📍 Pinball Machine 📍 📍 📍 📍 Putting parts on the deck For assembly, most parts simply interface with one another. Around the flippers, the ‘inner runways’ and the ‘kicker’ shown in Fig.30 require about 33mm separation to make the alleyways. For the rest of the deck, refer to Photo 23 and the lead photo. Now that you have a deck layout and your game design sorted, let’s get it running. Power supply & controller This final article in this series shows how we went about finishing our pinball machine deck and integrating all the electronics, wiring and electromechanical kit. We will also provide pointers and tips on the wiring, layout considerations and how to test and modify the design. Mount the assembled and tested power supply and controller boards to the back panel of your backboard. We used 10mm-long M3-tapped standoffs (spacers), marking the location of drill holes using the PCB as a stencil. With them mounted, connect the 6-way headers between the Power Supply and Controller boards. These Australia's electronics magazine siliconchip.com.au 74 Silicon Chip are straight across and should be simple. Use heavy-duty wire. Drill a 13mm hole in the rear panel and install the chassis barrel plug. We glued ours in place. Wire this to the Power Supply Board, making sure that the polarity is correct. Use a multimeter to check your connections. We assume that the controller has already been verified as working. Apply power and check that the heartbeat LED flashes. If not, unplug your power supply and check that it is OK. Run the Controller from a USB connection to your computer. If this does not get the LED flashing, reload the software. Check the 5V rail is OK; this really only drives the LEDs. Check for short circuits or parts not installed properly. The back box How you approach the back box is a matter of your style. We assume that, at a minimum, you want to show the score and player number. It’s also a good idea to put a speaker or speakers in there, as well as some form of lighting. Install the score and player PCBs to your backbox first. We have provided bezels that you can print to make these tidy, which you can glue to the backboard. We used 12mm-long 6G wood screws to gently hold the PCBs in place. Install the speakers and the grille(s) of your choice. We painted the interior of the cut holes black, which made our hand-cut holes invisible. ~33mm ~33mm ~3 3m ~3 m Next, work out how you want the lighting installed. You can use LED strip lighting, which is kind of expensive but easy to install, or individual LEDs, which you can install in LED holders. This may form part of your front panel design. Since the strip lighting is designed for a 12V supply, cut it into two strips and wire them in series to suit the 24V DC supply. Wiring it up Now let’s do some cabling. Cut the 1.5mm-thick aluminium bar into 140mm-long and 10mm-wide lengths, then bend them into an 80mm-long, 25mm-tall bracket shape, as seen in Photo 24. Slip large-diameter heatshrink tubing over the brackets and shrink it so that the edges of the metal don’t cut through wires (or wrap them in some kind of flexible plastic). Drill holes in the flanges for screws to mount them. There are other options, but you will need something to keep the cabling under control. Otherwise, the wiring will become a nightmare! Start the wiring with the score and player headers. We pulled the ribbon cable through the brackets to the PCB and cut lengths about 100mm too long. We then installed the crimp connectors on the controller end and reinstalled them to get the lengths right. Pull the cables and install the final crimped connectors. Use a labelling machine to label every cable, otherwise, by the time you finish wiring this up, you will never be able to trace cables through the loom! If you don’t have a labelling machine, you can use small paper labels (ideally laminated) or tags. Make sure the labels are legible and not confusing. Connect the speakers in series to get a 16W impedance. The LM384 is operating from 24V DC and should not drive a 4W load. Measure and install the speaker wire to the Control Board and label it. Now apply power and check that you get sound and the scrolling message on the score display. Remember that the rightmost two characters on Photo 1 (reproduced from part 1): you could create an exact copy of this, using the files and diagrams supplied, or do your own thing. 3m m Fig.30: the arrangement of the inner runways and the kicker. siliconchip.com.au Australia's electronics magazine October 2026  75 the score display are not used except in scoring. If you run into trouble, check the power supply rails. Verify that the heartbeat LED is flashing; if not, unplug the displays and find the short circuit. Hold down the self-test button at power-up and connect your computer running serial terminal software to debug these outputs. Check that the inputs and outputs make sense. Run the LED self-tests and, if you find a problem, check the cabling between the controller and LEDs. Lower deck section There is a fair bit of wiring even in our relatively simple demonstration build. This is shown in Photo 4, reproduced below (from part 1 of this series). We are proud to have kept this under control and avoided the chaos we have seen in many traditional pinball machines. If you use labels and our recommended wiring system, you will get a similar or better result. Install the loader sections as well as the flippers and associated runways. Make sure that the deck sections fit tightly together and double-check that the screws for the solenoids are secured with Loctite or similar; if they come loose, it will be a hassle. You will need to install Switch Input and High-Current Interface boards Photo 23 (left): our deck, shown previously before we got to assembling all the electromechanical parts. The ramp is pretty fun; the ball goes over a rollover as it exits that causes all the lights to flash brightly. You can decide how much of this you want to copy and what you want to change. Photo 4 (right): this view (reproduced from part 2) shows all the wiring under our deck. As you can see, there’s a lot going on, but we kept it all pretty neat and nothing is too difficult. Working on the wiring is actually quite easy. Note our “home made” tilt switch made from fencing wire and a handful of screws in the bottom left. 76 Silicon Chip Australia's electronics magazine siliconchip.com.au under the deck, which is easy to do using 20mm-long 6GA wood screws and the 3D-printed 8mm spacers. The exact location does not matter, provided it does not interfere with your mechanical parts – refer to Photo 25. The Switch Input board has inputs for: The Cascade LED sensor that triggers the triangular cascade LEDs An optional tilt input The Start Game button The Coin button/mechanism The Game Lost sensor input The Player Add button The Left Flipper trigger button The Right Flipper trigger button We used inductive sensors for both the Game Lost and Cascade sensors. This board has 24V supplied to it and can power standard sensors. You could use more conventional microswitch sensors for these if you want to. The inductive sensors are mounted in 3D-printed holders, as shown in Photo 26. The Start Game, Coin and Player Add switches are standard pushbutton switches, while our tilt sensor was made from fencing wire with a simple weight to detect the machine being tilted. SW-200D, SW-420D and SW-520D pre-made tilt sensors are also available inexpensively on websites like AliExpress. Install the Coin, Player Add and Start buttons on your case. Our arrangement is shown in Photo 27. Also install the left and right flipper buttons to your case. We used large 📍 📍 📍 📍 📍 📍 📍 📍 arcade-style switches that have the right ‘clicky’ feel. The Game Lost sensor needs to go right where the ball sits in front of the reloading mechanism, as the software uses this sensor as an input to detect when the ball is lost and needs to be reloaded. All the inputs are labelled on the PCB, and you can neatly wire these inputs through to them. Label the plugs, as all the wires look alike. Later on you won’t remember what each connects to! You need to run heavy-duty speaker wires for the Launch, Reload, Left and Right flipper solenoids from the controller to the High-Current Interface Board. Make very sure that you get the polarities right, as while the solenoids are not polarised, the flyback catch diodes on the High-Current Interface Board certainly are. This board has four identical channels, which are not labelled. Use them however it is convenient – just ensure that you connect the solenoids to the right outputs. We can now test the lower deck section. 01 Apply power to the machine. The system should power up. 02 Run the Self-Test routines and test each part individually. You should be able to push each of the buttons and see the test routine report that they are pressed. 03 Put a steel object on the inductive sensors and verify that this is Photo 25: the power wires from the Controller come in on the left to the High-Current Interface Board, as does the 10-way ribbon cable for I/O lines. They route to your local parts and sensors from here. Photo 24: the control board, power supply, score display and one speaker mounted in the back box. Note the brackets below and to the right of the control board that went from a piece of aluminium and covered in heatshrink tubing. We used several of these to keep the wiring looms neat. siliconchip.com.au Australia's electronics magazine October 2026  77 reported in the test routine. Most sensors also have LEDs on the back that will show you they are working. 04 The self-test routine also has the ability to test the solenoids. Run these tests and check that the flippers and loaders actuate as expected. If not, verify that the inductive sensors are wired correctly, check the ribbon cabling for the inputs, and examine the power wiring to the solenoids. If the polarity is swapped on the power connections, you will damage the flyback diodes and possibly the Mosfet (as we unfortunately found out). Installing the LED lights We have made 3D printable bezels that accommodate 5mm LEDs and are a push-fit into holes drilled in the deck. These use 8mm, 10mm and 12mm diameter bezels that we printed in clear PLA (we liked the 12mm type). We drilled the deck and installed these prior to painting it. These were used for all LEDs on our deck; the files are in the Led_Holder folder. You can use a hammer to get them in if needed (but you must hammer from the top of the deck). Those that are not tight can be secured with a drop of superglue on the rear to hold them in place. During painting, we cut 12mm diameter circles from contact adhesive and stuck these on the bezels so that the paint wouldn’t cover the clear windows. To do this, we sharpened the end of a piece of 12mm copper water pipe and used it as a die. You could also use a 12mm leather punch. The cascade LEDs can fit directly into the bezels if drilled as shown in Fig.19. The cascade LEDs can be jiggled into the bezels and secured with a drop of superglue between a couple of the LEDs and their bezels. The circular LEDs around the bumpers can also be drilled as shown in the diagram, and the target LEDs placed directly in front of each target. The circular bumper LEDs install similarly to the cascade LEDs. Both sets connect to the labelled headers on the controller board using 10-way ribbon cable, which you should run through the cable loom. The target LEDs need to be wired via one of the LED breakout boards. Fig.19 (from part 3): the holes in the deck for our Pinball Machine. Note the rectangular cut-outs for the targets & kickers. You will need to fettle them when installing those parts, but it’s better to start with them too small than too big! 78 Silicon Chip Australia's electronics magazine Installing the targets The cutouts for the targets are shown in Fig.19 (from part 3). These can be siliconchip.com.au Photo 26: there are versions of this 3D print for 8mm and 12mm diameter sensors with two, three or four screw holes, allowing you to get sensors into tight places easily. There is a grub screw hole in the rear of the holder to secure the sensor. Photo 27: our front panel is pretty simple. We used stencils to spray the labels, which are in the download package. You need all three inputs to the Controller for the three buttons. We installed the launcher while we arranged the lower deck sections. cut using a handsaw. We needed to do a little fettling to get the holes to just fit the target assemblies. We drilled 12mm holes for the target LEDs, which light up when you hit a target. The targets screw to the underside of the deck with 16mm-long 6GA wood screws. You need to install the General Input and General LED boards under the deck. We placed ours on one side of the deck, as shown in Photo 28. It is a touch hard to see in the pictures here, but each has a 10-way ribbon cable that runs from the interface board through the wiring loom to the respective input and output connectors on the controller board. Wiring from the target microswitches to the input board is via light-duty hookup wire and polarised header plugs. Label these, but if you get them in the wrong spots, you will simply have the wrong LEDs lighting when you hit the target. We zip-tied these all together to keep things tidy under the deck. Testing the LEDs Apply power to the system with the Self-Test button held down. Run through the tests until you get to the appropriate LED tests. You should have tested the LEDs on the PCBs earlier, which is important if you are gluing them into the deck. If these tests fail, you most likely have a problem with your plugs or crimping. Are both plugs the right way around? Did they crimp properly? Swap them with other LEDs to see if they light up . Are the individual LEDs wired the right way around? Installing bumpers & kickers The kickers need an odd-shaped hole in the deck, as shown in Fig.19. We cut a rectangle using a handsaw, then made the extra notch cutout. As we installed the kicker, we found that we needed to extend the cutout somewhat. We did this using a file and knife, avoiding cutting too large a hole, which would make the deck unsightly. We installed the posts and the top of the kicker, which are 3D-printed from the files “Square Rope Kicker” and “Posts Top L and R” in the Posts Photo 28: the labelling makes this a little messy, but it’s absolutely necessary if you plan to remove or service parts later (and you almost certainly will need to). siliconchip.com.au Australia's electronics magazine October 2026  79 folder. These secured using M4 × 50mm machine screws and hex nuts. We used 5 × 5mm neoprene rubber for the kicker ‘rope’ and superglued this into a rubber band that was tight on the posts. The kicker mounts with its foot just next to the ‘rope’. Screw it into place under the deck using 6G × 16mm wood screws. You need four kicker microswitch brackets in total. These mount under the deck with the microswitch lever touching the rope. Once secured using 16mm wood screws, adjust these by bending the lever with a pair of pliers so that moving the rope a little causes the switch to activate. Getting this right is important, but once set, the adjustment is stable. The bumpers fit through a 25mm hole in the deck that you can drill using a spade bit. The edges of this are hidden by the skirt, so a little tearing on the edge of the drill hole is OK. You need to print and install the bumper shim, which provides extra clearance for 12mm LED holders and makes construction easier. Assemble the upper and lower deck parts of the bumper, as described last month. We set the gap between the ball sensor and deck to about 2mm and ensured that the sensor worked well. If the sensor does not work at some angles, check that the microswitch is square in the recess in the bumper assembly – once located properly, this should operate reliably. Screw the bumper to the deck using 16mm wood screws. Once adjusted, fix the upper and lower sections together using four 9mm self-tapping screws. Put 2.54mm pluggable connectors on the ball sense and LED outputs and two-way terminal block plugs on the solenoid wires. These will need to have sufficient length to reach the interface board. Plug all of these into the labelled locations and you are set. You need to install the Bumper Driver Board, as shown in Photo 29. Like all the under-deck PCBs, we mounted this using the 3D-printed 8mm standoffs and 6G × 20mm wood screws. As with all the power and control interfaces, run labelled 10-way ribbon cables with IDC connectors from this board to the matching connectors on the controller board. Also wire the bumper and kicker switch outputs to the interface board. The kicker microswitches are wired in parallel, so there is only one wire going to the header on the interface. To test the kickers, first double-­ check that the power cabling has the right polarity. Boot the machine in Self-Test mode and you should be able to detect the sensors being pressed for the bumper and kickers. If only some fail, you have a wiring problem. Find it and fix it. If all fail, check that the IDC headers are both on the right way. Then run the power tests. You should see the kicker and bumpers actuate during those tests. Installing the upper deck sensors We installed several rollover sensors on our Pinball Machine, using inductive sensors, as described earlier. We have three between the runways at the top of the deck, one at the exit of the launch runway up the right hand side of the deck, and one at the exit of the tunnel. These all connect to the Rollover Board, which you need to install at the rear underside of the deck. The inductive sensors connect to the rollover board using three-way pluggable headers. On ours, ground was blue, +24V was brown (you could use red) and the open-collector output was black. Use the printable holders for these, which are in the “Sensor Brackets” folder under “Lower Deck Runway”. We used 12mm sensors. These affix under the deck using 16mm wood screws and you can use a small self-­ tapping box screw to secure the sensor into these holders. Get the top of the sensor flush with the deck. We painted over ours. The rollover board connects to the controller with a ribbon cable. To test the sensors, run the controller in Self-Test mode and put a metal object on each sensor in turn to see the input toggle. If you have problems, check that there is 24V supplied to the sensors and verify that the cabling is right. Remainder of the upper deck The remainder of the example upper deck is runways and posts. Yours may differ, but you will surely have some structures and sensors in there. Ours is shown in Photo 23. The 3D-printed parts for our example deck are in the “Runways” folders Photo 29: there’s quite a lot going on in this area including the flippers and their interface, two kickers and many individual LEDs. You can also see one of the bumpers and the bumper/ kicker interface board. We found that labeling things on the underside of the deck helped us navigate our way around during set to work. 80 Silicon Chip Australia's electronics magazine siliconchip.com.au and “Posts” for the posts. We suggest that if you are starting with the example deck, you print these and lay them out on your deck. While we have shown hole locations in the drawing, we would simply place these and screw them down using 16mm wood screws. The posts are placed 43mm apart, which gives room for the thick cloth-covered rubber band we strung between the posts, allowing the 22mm ball to still pass through. With all these in place, you should have everything sorted out and be ready to sand and paint the deck. Painting the deck This author is no artist. After some head-scratching, he came up with some ideas for the theme and deck. We leave the decoration to your imagination and would love to see what you come up with! You can get stickers and decals for pinball machines. While not cheap, these may be worth considering. The pinball surface takes a beating, so if you’re painting the artwork, it needs to be protected with a clear coat. One tip, which I expect every professional painter will know: if using clear coat over a range of different manufacturers’ colour coats, apply many thin layers of clear coat to build a protective layer. Otherwise, you may find the colour coat will bubble or fail. Playing the game We are sure that by this time you have been playing the game in its various states of build; we certainly were. The flow of gameplay is: Boot the machine, which plays the introduction sound clip ‘Insert coins’ by pressing the Coin button. This is announced audibly. Choose the number of players, 1-4, using the Add Player button. Press the Start button, wait for the ball to drop into place, then launch it. Use the flippers to stop it from going into the gutter (if you can). The game will run until each player loses three balls. On Game Over, the player scores are displayed and the system returns to the idle state. 📍 📍 📍 📍 📍 Changing the sounds We have used license-free sound clips as part of the game. These can be changed reasonably simply, but you will need to install the compiler and siliconchip.com.au Pinball Machine Kits Control Board (SC7659, $150) includes the PCB and all non-optional onboard parts Power Supply (SC7680, $50) includes the PCB and all onboard parts Cable & Connector Set (SC7681, $65) includes 17 10-pin box headers, 34 10-pin IDC connectors, 10m of 10-way ribbon cable, 30 2-way pluggable terminal blocks and 20 2-way polarised headers. build new sounds into the application. In the “Sounds” folder (in the download package, under Visual Studio files), you will find the WAV files we used for our sounds, as well as many “.h” files, which we need to copy into the C source folder. There is also a utility called “main.exe” that runs on a PC. This converts a 44.1kHz stereo WAV file into an 8-bit, 11kHz mono header file that you simply copy into the source folder. The syntax for this program is: main.exe INFILE.wav OUTFILE.h This utility puts all the data into the header, including the length of the clip. It can’t be more than a few seconds long. You will need to copy the generated files into the source folder and rebuild the application. The sound files are all stored in the following header files. The names are hopefully self-explanatory: • Runway_1.h • Runway_2.h • Runway_3.h • Pattern_Sensor.h • Launch_Sensor.h • Tunnel_Sensor.h • Bumper_1.h • Bumper_2.h • Bumper_3.h • Kicker_1.h • Kicker_2.h • Targets.h • Start_Runway_Sensor.h • Flipper.h • Coin.h • Player.h • Launch_Are_You_Ready.h • Credit_Needed.h • Player_1_up.h • Player_2_up.h • Player_3_up.h • Player_4_up.h • Ooooh.h • Game_Over.h Changing the software The rest of the source code is also in the Visual Studio folder that’s part Australia's electronics magazine of the download package. We hope it is reasonably self-explanatory. Key aspects of its operation were described in the first article in this series, including a state machine diagram. The state machine calls quite simple functions that update things like the current player number, score and such. The RunGame state is critical in that it repeatedly calls five main functions: 01 Check_Inputs() reads the 32 serial inputs and when they change between calls, triggers either light updates, power updates or game parameters like BallLost. 02 L i g h t s _ U p d a t e ( ) r u n s a sequencer for light patterns. The software is capable of generating multiple complex light patterns and sequences; our example program keeps this simple. You could change this significantly. 03 Power_Update() drives the output Mosfets. There are several defined variables for the on and off times, with the ability to sequence these. Again, our example keeps this simple. 04 set_score_display() updates the score display. 05 set_player_display() updates the player display and moves on to the next player. Conclusion This is a monster project; one of the largest ever presented in this magazine. We hope that if you take it on, you have a lot of fun and make a pinball machine that’s a blast to play. Please send us photos and videos of the finished product! Given its scope, and despite the extensive instructions presented over the last five issues, we wouldn’t be surprised if constructors occasionally need to ask questions. Please email us in that case, via the general Silicon Chip email address, and we’ll do our best to get back to you with a useful answer by the next business day (if SC not sooner). October 2026  81