Table Tennis Scoreboard

by joshpit2003

18K17334

Intro: Table Tennis Scoreboard

Too lazy to keep track of your Table Tennis / Ping Pong score?
Or maybe your just sick of always forgetting it?

If so, you may be interested in building this digital Table Tennis Scoreboard.

Here are the highlights:

  • Tracks points, games, server, and playing side.
  • Mounts to a wall, cubby, tabletop, or tripod.
  • Pre-programmed to play official table tennis rules.
  • Record each point with the press of a button.
  • Wireless buttons last 5+ years on a coin cell battery.
  • Ultra power-efficient display.
  • Easily visible with large 5" bi-color 7-segment numbers.
  • Display itself can also be battery powered.
  • Many pre-programmed adjustable parameters.
  • Arduino based chips and programming language.

For more fancy product-shots, please visit my website:
https://rapidwhale.com/scoreboard.php

Thanks, and enjoy.
-Josh!

STEP 1: Gather Your Supplies

You can build your own referencing these open source files.
or you can buy a complete DIY Kit from my website.

Here is everything you will need:

Laser Cut Parts:
- Included in kit.
- or cut them yourself with the open source files.

Printed Circuit Boards:
- Included in kit.
- or wire your own on prototyping board referencing the open source wiring schematics.

Electronic Components:
- Included in kit.
- or purchase your own referencing the open source bill of materials.

Safety Glasses
- To protect your eyes from the nasty things like acrylic glue and sharp electronic component leads that will go flying when you cut them.

Wood Glue
- To glue the housings, which are mostly wood. You could probably use any CA / Super Glue as well, but for this project I preferred to use Tacky Glue or Elmer's Wood Glue.

Acrylic Glue
- I like the Acrylic Cement from TAP Plastics. You can use CA / Super Glue as well, but that is likely to fog-up the acrylic (which might not matter if you careful in your application and cleanup).

Clips / Weights
- Binder clips and weights are great for holding pieces as the glue cures.

Soldering Iron / Solder
- To solder many electronic components to PCB's / prototyping board. Best to use a small "pencil" soldering iron. I'm a big fan of Kester 44 Rosin Core 63 / 37 0.031" Solder (pictured). Be sure to solder in a well ventilated area and ideally with a fume-extractor.

Wire / Wire Strippers
- To make connections between PCB's or on prototyping board. I used 20-22 AWG wire.

Paint Marker (or just paint)
- To apply in areas where we don't want light to shine through the acrylic.

Basic Tools
- A phillips screwdriver, flush diagonal cutters, needle nose pliers, and a small amount of sand paper should do it.

STEP 2: Build the Buttons (Acrylic)

Reference the exploded view then:

- Begin gluing the acrylic.
- Insert the hardware (QTY: 2 of M2.5 hex nuts per button).
- Finish gluing the acrylic (Use the PCB / prototype board as a jig to ensure proper acrylic part locations before gluing).

STEP 3: Build the Buttons (Wood)

Reference the exploded view then:

- Begin gluing the wood (Part orientation is critical).
- Flex the wood with extreme care (It is quite fragile as this point).
- Spread the glue liberally along the inside to increase part strength.
- Run glue along the corners, pushing it into the laser kerf cuts to greatly increase part strength.
- Use the Acrylic part of the button as a jig to ensure the wood glue dries such that the button housing will fit the acrylic piece.
- After the glue is dry, sand lightly to along the outside to remove excessive glue-spots.

STEP 4: Build the Display (Acrylic)

Reference the exploded view then:

- Remove the protective backing from the surfaces to be glued.
- Begin clamping and gluing the acrylic.
- Insert the hardware (QTY: 12 of M2.5 hex nuts and QTY: 4 of M4 low-profile hex nuts).
- Finish clamping and gluing the acrylic.
- Paint the white surfaces as shown to ensure light does not pass through the acrylic (it is important that your paint is as opaque as possible to ensure it blocks the powerful light of the LEDs that will be resting just behind this surface).

STEP 5: Build the Display (Wood)

Reference the exploded view then:

- Lay out the pieces in a logical manor.
- Cut out the circle(s) depending on how you plan on mounting the display (Think about how you want the power cord to enter the display and cut out the hole accordingly, and cut the center-most hole as well if you plan on mounting it to a tripod).
- Begin gluing the wood.
- Flex the wood with extreme care (It is quite fragile as this point).
- Spread the glue liberally along the inside to increase part strength.
- Run glue along the corners, pushing it into the laser kerf cuts to greatly increase part strength.
- Use the Acrylic part of display as a jig to ensure the wood glue dries such that the display housing will fit the acrylic piece.
- After the glue is dry, sand lightly to along the outside to remove excessive glue-spots.

STEP 6: Solder the Button PCBs

- Collect the required electronic components.
- Insert the small components according to the PCB silk-screen
- Solder the small components and trim the excess leads.
- Insert/solder/trim the other components (The dip-switch and tactile-button are inserted on the opposite side as shown. Not the orientation of the dip-swith).
- Insert the pre-programmed micro-controller, radio, and battery (Polarity is critical).

Build both identical PCBs.

STEP 7: Solder the 7-Segment PCBs

- Collect the required electronic components.
- Insert the BLUE LEDs (As shown) taking note that the PCB silk-screen indicates the LED positive (+) lead-locations, and also indicates the different color LED locations (solid-bar = BLUE, no-bar = GREEN).
- Solder the BLUE LEDs and trim the excess leads.
- Insert/solder/trim the GREEN LEDs.
- Insert the resistors and 16-pin housings (on the back side of the PCB, opposite of the LED's). There is a notch in the 16-pin housings, position it according to the silkscreen on the front of the PCB.
- Trim the resistor and 16-pin housings completely flush on the front of the PCB

Build all 4 identical PCBs.

STEP 8: Solder the Game Marker PCBs

Build both identical PCBs in a similar fashion.

STEP 9: Solder the Brain PCB

Build this PCB in a similar fashion.

- Take note of the important text in the attached photos.

STEP 10: Complete the Final Wiring

Time to bust out that 20-22 AWG wire. If you have 5-wire ribbon cable (not pictured), that would make this step a little easier.

- Position your Brain PCB, Rocker-Switch, and Barrel-Jack accordingly so that you know what length to cut your wire (Cut the wire with a few extra inches for ease of assembly).
- Solder the + / - leads to the barrel jack (+ lead is the one connected to the center pin as shown).
- Attach the crimp connectors as shown and solder onto the Vin of the Brain PCB (Don't push the connectors completely onto the rocker-switch until we are doing final assembly).
- Cut your wire to length and solder it on as shown to connect all of the PCBs.
- Trim the solder-joints flush with the PCB's facing the display (otherwise they will not rest flush against the back of the display).

Your end result should look just as neat as pictured.

STEP 11: Clean the Display Acrylics

- Wash any residual laser-smoke from each piece (Block the drain or do not work in a sink to ensure no parts are lost).
- Lay them all out to dry.

STEP 12: Assemble the Button

- Collect the required components and assemble the buttons as shown.

STEP 13: Assemble the Acrylic Display

- Collect the required components (Hopefully all of your display acrylics are dry by now).
- Remove the protective backing from both sides of the acrylic backing-plate.
- Drop in all of the frosted display acrylics.
- Cover the frosted display acrylics with the backing plate.

STEP 14: Assemble the Display

- Lay out the required components as shown.
- Fit the PCB's to the display acrylic piece and secure them with the M2.5 x 6 machine screws and washers (do not over-tighten).
- Attach the rocker switch as shown.
- Secure the Brain PCB to the housing with the same M2.5 x 6 machine screws and hex nuts. You may need to remove a button-cover or two to fit the PCB, then push the button covers on from outside of the housing.
- Secure the barrel-jack through whichever hole you chose to knock-out (The washer and nut go on from outside of the housing)
- Sand the lip of the housing to ensure a smooth, easy installation of the display acrylic.
- Fit the display acrylic (If it isn't going on without much force, check clearance and sand accordingly).
- Secure the display acrylic with the QTY:4 of M4 x 45 machine screws.

STEP 15: Setup / Test

- Set the Button and Display dip-switches accordingly. The #1 digit on the dip-switches for the wireless buttons tells the display which wireless button it is communicating with it. The #2 through #4 digits on the dip-switches is for setting a channel (There are 8 possible channels, which means up to 8 Table Tennis Scoreboards can work independently in a single room).
- Peel off the protective backing on the display acrylic

*** Moment of Truth ***

- Plug in the wall-wort and power up the display (It should look as shown).
- Cycle through the different settings, and test the wireless buttons are working. If you notice any dead or flickering segments on the display, it is likely a result of mishandling the accompanying LED. If so, it will need to be replaced.

STEP 16: Enjoy

I suggest mounting the wireless buttons with industrial strength hook-and-loop (Velcro). I'd suggest mounting them under the table, directly in the center if possible.

Be sure to check out the other pictures and the DIY Kit on my website: https://rapidwhale.com/scoreboard.php

Thanks.
-Josh!

29 Comments

FlorianHan2023 1 year ago

Hey, I love this project and it is exactly what I was looking for. I would love to build one myself but I really need the PCB'S for this. Please let me know if you sell those seperately. Cheers

joshpit2003 1 year ago

Hey Flo. I got your email. I've just been lazy. I'll respond (via email) in the next hour. For anyone else reading: I never did uploaded the PCB manufacturing files. I may still have them on a hard-drive. Perhaps if enough people bug me then I'll get around to posting them. When I originally did this project, I was expecting people to either purchase the Kits or, if they weren't gonna do that, then they would just solder up their own circuits. At the time, single-run PCB manufacturing wasn't really cost-effective. I ordered a small batch of 6 or so, and I think I'm down to the last 1 or 2.

joshpit2003 4 years ago

I just checked my DigiKey order history, and it looks like I have substituted that inductor part in the past with 732-3082-ND. So my best guess would be: Yes. I think that part you linked-to will suffice. As for the missing RED led from the BOM: Thanks for letting me know. It's been years since I wrote that BOM, and as far as I know only you and one other guy have ever used it. So for that reason I'm not sure that I'll ever get around to updating or fixing it. Hopefully I got everything else right. Regarding the PCBs: You can reach out to me through my website.

DaveW227 6 years ago

I would like to see a unit without the remote control options as in league table tennis an umpire will keep score and he/she would require the buttons to increment the score. Furthermore, a button to "undo" a point in case of any mistakes. These buttons would be on the rear of the main display unit. The umpire would place the unit on a table with the display facing the players. The umpire would sit behind the table

Add to this a second smaller display on the rear of the unit facing the umpire so he/she can see the current score. The main display will be facing the players. You can see that the player to the umpire's right would have his score shown on the right on the umpire's display and on the left on the main display.

With these suggestions implemented the unit would be suitable for current league table tennis matches.

joshpit2003 6 years ago

I understand what you are requesting, but as currently designed: The umpire would just have to sit on the opposite side of the scoreboard with both wireless buttons acting as a remote control. That way the umpire and players are all looking at the same scoreboard.

The beauty of this scoreboard though is that it doesn't require an umpire. If you have an umpire, just hand him the wireless buttons (they last for years on a single coin-cell battery). If you don't have an umpire, just attach the buttons to the table for the players to hit.

As for reverting a mistake, that is already implemented into the code. Just hold down either player button and the game is reverted to the previous score.

Hope that makes sense.

AndrewHoover 6 years ago

Very Nice!

Excellent work! Well thought out and explained!

beul 6 years ago

amazing, super works, i like it, thanks for share

danielrp 6 years ago

Awesome design. Great project!!

Antzy Carmasaic 6 years ago

Great project. Except for the kerf cut rounded edges, can this be made on a CNC router? I recently got one and am looking for projects to try out.

joshpit2003 6 years ago

If you had a small enough end-mill, then you can probably get away with most of the existing CAD, but you may still need to tweak a little of it it to make up for your end-mills radius in corners. I bet you could do the kerf cuts with a small, steep-angle cutting bit, such that you are cutting what will be the inside of the radiused corner.

joshpit2003 6 years ago

actually, I take it back... the radius is just way too small for you to have any success partial kerf-cutting with a router. You would just wanna make the corners separate.

SeanB10 6 years ago

Fantastic work! Now how do I get better at ping pong?

joshpit2003 6 years ago

It helps to own one that is set up in your living room and written off as a business expense. ;-)

seamster 6 years ago

As an avid ping pong playing family, this would eliminate half the fun of our games: arguing over the score! ;)

Great instructable, very well documented!

joshpit2003 6 years ago

lol. Maybe it could add in a new element of trying to sneak in a button press when the other player isn't looking (or listening if you have the "beep" function turned on). ;-)

aathish04 6 years ago

Im assuming you can 3d print these parts as well?

joshpit2003 6 years ago

They could be, but 3D printing isn't great for large flat shapes; laser-cutting is.

aathish04 6 years ago

Ah, thats true. Thanks for the info!

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