Electronic Wall Mounted Chess

by Artless Dodger - April 2014

artlessdodger@wallchess.co.uk
        

Please note.
This guide was never intended for public viewing and was written as reminder to myself after I had completed the project. As such it is very poorly written and intended as a reference to prompt my memory if needed in the future. It most likely goes into depth on some topics and completely skips details on others. Please read through entirel;y before embarking on this project as I may have listed things in or out of order of assembly!
Since this page has been getting hits, I have edited it somewhat but please accept my apologies for any grammatical atrocities from here on out.

Skills Needed:

Intermediate Soldering skills
Basic electrical understanding of circuits, continuity testing , polarity testing etc.
Basic woodworking skills


Tools needed:

Box cutter
Screwdriver
Soldering iron
Multimeter
Pliers
Drill
2mm wood bit
3mm wood bit
4mm wood bit
5mm wood bit
6mm wood bit
Drill press
Hack saw
Tenon Saw
Mitre block ( for cutting right angles and extending frame depth if necessary)
Staple Gun
Long metal ruler
Right angled set Square
Sharp pencils
Sand paper


Parts Needed

Working Fidelity Chess challenger 8 or 9
Power adapter 8v
Coin cell battry 3v
MDF 6mm board 410 by 710
Brown or black leather half square meter
White or cream leather half square meter
Cable straps (Thin)
Acrylic glass 10 * 400L *30mm Deep * 6MM thick (2 spare)
Leds , 3Vm blue and red,
30 cms fibre optic wire ,(you only need about 10 inches.) side glow or end glow is fine.
Kynar single core 30awg transfer wire,or equivalent 30awg stranded wire. various colours
Momentary push buttons (8mm pole)
Function Buttons (built in 3v Led blue)
KIT circuit
All purpose adhesive
Sheet plastic , thinner than credit card, thicker than paper, (think phone screen protector)
Wooden frame with interior opening 400 *700 and with a 5mm underlap. If you can only get 8mm underlap youíll need to adjust size of the board



I was browsing in search of a new project recently and came across a picture of a vertical chess set mounted on a wal and thought how cool it was, as both a great project to build and as a novelty piece of wall art.

Iím fairly fond of chess so decided to give it a go. My first project resulted in the below wall chess. These are wood veneer squares and obviously not electronic. Construction was much simpler and aesthetically very pleasing and in a lot of cases you may want to just go along with that style.

   

I Played a few games on it by using the chess app on my iphone and moving the pieces respectively, but then I started thinking it would be a lot cooler if the wall chess could actually play against me itself rather than me referring to a separate chess computer all the time. I also wanted to keep the overall look of the first board so that meant keeping visual electronics out of site. You really wouldn't know it was an electronic chess if you didn't switch it on.

For the wall chess mark 2 I started researching electronic chess computers.

After a bit of research and reading through a couple of websites from people who had also repurposed old chess computers , linked here as they are pretty fascinating projects in themselves,

SishFishPi
Solus Chess

I reached the conclusion that there were two ways to go with the build. Either an auto sensory board or a push button sensory input board.



Iíll explain the difference in boards quickly.

Auto sensory= lift up a chess piece and simply place it on the square you want to move to and the computer recognises the move automatically by means of a reed switch located beneath the playing surface. The chess pieces usually have a small magnet built into the base which activates the reed switch,

Press button= lift the piece, press against its square and then press the intended destination square. So as you can see. Auto sensory would be way cooler, albeit a little more work, (I have a plan how to do it but need a board and the time before embarking on a Mark 3 version)

If you browse eBay, youíll quickly realise that the auto sensory boards are somewhat of a collectorís item and are pretty expensive where as the press button input type are fairly common and a lot cheaper.

The second decision I made was that i wanted each square to have its own LED indicator.

This narrowed the search down considerably until I came across a suitable donor computer which was quite common and fairly cheap whilst still having a fairly good skill level setting.
Enter the Fidellty Chessmaster 8


As you can see, this board has an led assigned to each square and operates on press input. It also has a limited amount of functional buttons (8) meaning I wouldnít have to add too much additional wiring.You can see them up the right hand side of the board along with the thinking LED which we'll mod later.


Many of the older chess computers have a small lcd display which indicates the computers desired move by flashing up coordinates. Having an led that simply blinks seemed far simpler.

Board Design


On average, the King in an average chess set is 75 mm) This meant that each square needed to be at least this height to accommodate the average set, The King always being the tallest piece in a chess set. Width I decided simply for ease of calculations at 50 mm. In the end decided the squares would be 80mm by 50mm.

Next I calculated I needed 5 mm between each row for the shelves These I got from these guys The measurements of the shelves weíll get to later.

I also wanted to align all the functional switches on a separate row beneath the board I also needed to calculate the overlap of the frame I would be using.

Once that was calculated i ended up with a board of MDF 6mm thick and 410mm * 710

8*80mm with 5mm spaces between each row and an additional 200mm for the functional strip at the bottom and also again the 5mm undelap at top and bottom

8*80= 640

8*5mm led gaps = 40mm

20mm functional strip = 20mm

2*5mm overlap top and bottom= 10mm

Totals 710mm * 410mm



The easiest way to visualise is this is with the image below I created in excel. IMPORTANT the bottom right square should be white, not black like i have depicted, Just donít assemble it with a black square there or it will be wrong. The official chessboard always has a white square in the bottom right ok, youíve been warned.



Marking the board is fairly straightforward. Mark a 5mm border around the whole board ( *** Important, you will need to know what the recess is on your frame to get this measurement correct. Most frames have between 8 and 10mm underlap) and then put your 80 mm by 50mm top 8 squares in.

Draw a 5mm gap and repeat until you have all 8 rows in. If done correctly, you will have a final 5mm gap beneath the bottom row, DONíT forget that one or the bottom row wontí have a shelf!! Below that youíll have another 20mm for the functional strip and another 5mm overlap below that for the frame. for the frame.

Now comes the fun part, Drill drill drill. Mark the centre of each square and drill a 4mm hole from the top. This makes sure any breakout is on the backside. You now also want to drill a 4mm hole in the centre below each square in the 5mm gap for the LEDS.



The functional button strip had holes also drilled to accept the 6mm buttons, so go ahead and drill 8 holes in the centre beneath each bottom square. The button itself is 6mm square but the cap is 12mm so will hide the hole and button when you affix the caps.

Now that all the drilling is done, you may want to go ahead and sand down the back of the board to get rid of all that rough wood.

Once smooth itís time to start fixing buttons.



I used momentary press buttons switches, which are ridiculously cheap. The stems are 8mm and the body is 6,mm

when these are put in the board they protrude 2mm above the surface of the board, Thatís just a bit too much, so placed a small washer 1mm thick between each button and the board, meaning only 1mm protruded which was more than enough.




Now I cut 64 squares of plastic 2cmm * 2cmm. I actually used an old iPad protective shield cover. That should give you an idea of the thickness you will need. It doesnít have to be clear but if it is it will help with the alignment. I glued these squares directly over the exposed button tops. My thinking as it would avoid any adhesive fouling the buttons later and also extend the hotspot area of the button later.

Once all the shields were in place its time to start applying the leather, I used a run of the mill glue you find in most newsagents, Bostik all purpose adhesive.







The leather I used is faux leather Vynl off eBay again. (search: Upholstery Leather VYNAL PVC VINYL FABRIC Leatherette)

All correct you should have 64 squares



Remember!!! IMPORTANT!! The bottom right hand corner square must be white!!!!

Glue all the squares down and pay particular attention to align up the edges and not get adhesive all over the front of the leather. Test that you hear a click of the button after every square.

Remember!!! IMPORTANT!! The bottom right hand corner square must be white!!!!

Leave the leather strip for the function buttons off for now as youíll find it easier to cut holes in it separately later

Wiring

If you havenít already done so, itís time to disassemble your chess computer. The model I used had two screws in the battery compartment and I think one on the back somewhere.

Remove the lid of the battery compartment and take out any old batteries. Unclip the battery terminals of the plastic housing if possible and Undo all the screws you see and then pry the unit apart. You can cut those battery terminals away if you want to at this stage.



You can disconnect the front from the back by carefully pulling the two flexes cables directly out of the connectors on the main board. You should now have two parts of the computer.

At this point I didnít take many photos but the important thing here is to understand how the board circuit works. There are two connection blocks on the main board. One for the columns and one for the rows,



Number the pins of these blocks with a marker pen and make a correlating mark on the flex cable of the board. Make sure you get the orientation correct this is so you can map the route of each pin from each connector.



Now you need to peel off the old playing surface off the plastic, once complete you will have the playing field in your hand like below



Wiring


To understand the circuit better, go ahead and peel the two layers apart. I used a hair dryer to heat it up so that it would peel apart easier. You want to try and keep the printed circuitry intact, just so that you can see and understand how each square is wired.





Take your time and look at each square. You can see it has a circle of silver. When the square is pressed, the circle of silver from one layer contacts the circle on the other layer created the contact and switch.

Each square has a track leading in and out in most places and all of them can be traced to one of the tracks on the two connector flexes at the top.

Youíre mission is to map those paths to the connector blocks on the main board so that you can replicate the circuits on the back of your board. Unfortunately I donít have diagram i can offer as I actually did mine one by one as I wired them. Referring constantly to the back of the playing field as I went to make sure it was correct.Below you can see the tracks and a silver circle of the one of the buttons.











You can also at this stage separate the main led board from the motherboard by carefully sliding the panel up and away from the pin connector. This will reveal a load of upright pins.

In order to get the circuit boards into the frame, I decided to replace the connectors with hard wiring. Itís a straight forward enough job but you do need soldering skills and a bit of patience.









It's not pretty and lessons were learnt on this stage.
I used single core Kynar wire to bridge the boards but with all the moving around the wires would break often. I must have had to resolder about 5 wires over the course on installation. Either use some flex cable, like the stuff you find in pc's that connect hard drives to motherboards, or some other more flexible ribbon flex. I'd be interested to hear what people use and to what degree of success.

Once you have all the squares circuitry mapped you need to replicate it onto the switches on your board. I held all my buttons in place using strips of plastic cut from cable straps and used a staple gun.

You can see the end result here.

I also placed all me LEDs into the holes and glued in place. Try to orientate the LEDs so that the positive (longer leg) is always facing the same way. This will help you later when connecting them up.





I initially just wired the switches up in a matrix, I didnít add the functional switches until later. In essence they are just extensions of the other tracks, more like an extra line of squares if that helps visualise it. Expect to spend the best part of an afternoon doing the wiring and I would highly recommend getting some bare connecting wire if possible. I couldnít find any at a decent price and ended up having to solder separate wires between each button instead of just wrapping the wire from one leg to another and so on without cutting the wire.

Once youíre happy with the wiring, use the multi-meter and test connectivity between the ends of each circuit. You can also test the buttons if co inclined by working out which two ends correspond to which button and pressing it.

Now figure out the function buttons and extend your wiring down to the bottom functions strip and wire them in place. Again note the polarity of the inbuilt LEDs . The most important buttons are the Reset and the CL . The other 6 are for when you get a piece to the opponentís rear file and want to promote a piece so not really critical but they do have extra features such as indicating where pieces are on the board and setting up problems.

Wait, The leather strip at the bottom still needs holes cut out for the switches to pass through. No easy method for this. I found a small piece of sharp pipe, a bit like a metal straw and sharpened its edges. I then basically stamped the holes out in the appropriate spots and then glued the strip on.
Ok, thatís the switches wired. Now time for the leds.

LEDs


Take a look at the LED board and mark on the board the corresponding square for each led.Also mark out it's polarity. The polarity of the LED's tends to be both ways so be careful when marking. It won't cause any damage if you get it wrong but the led won't light!
Now desolder all the LEDs. You can keep these LEDs for another project but for this job they are two big. Also work out the positive for each Led using a coin cell battery. You should get something like this.I took this picture half way through the wiring .



Now that you have the positive and negative for each bulb marked and the corresponding square attributed to it you can extend wires form each individual LED to the corresponding LED on your board. Thereís no simple way to say this but mine looked like a birds nest when I had finished and I was, and am very embarrassed about showing it. By the time I was finished I understood how to do it next time much tidier but by then it was really too late to start over. Take a look for yourself. Itís a darn mess.



Anyway, albeit messy, it gets the job done and is simple enough. Just make sure you get the polarity right. Itís useful to have a coin cell battery handy to check any polarity doubts.
You might also want to look at the ďComputerĒ thinking LED at this time and mark the polarity of that one. Itís a separate LED highlighted below. Itís next to the battery/dc switch. You might also solder a couple of wires to the dc jack so that you can attach the power later.



I aligned the boards up carefully on the back of the board and I placed a couple of 1 inch blocks of wood under the main board to keep it insulated from the backs of the switches and LEDís. I also threw in a piece of foam craft paper for good measure.

You'll notice that I have still not linked the flex cable connectors to the main board yet.



Using your map you made earlier you can now goahead and solder a wire from each connector across to the corresponding first button of your row or column. Note that one of the connectors has an empty slot on pin 4 so don't fall out of step when soldering.Take your time and test after each connection with the meter. Test continuity between the connector and the final button in the chain.
The function switches can now be wired in.



I bought a set of all the Alphabet and also a reset button and an Asterix/star looking one I use for the CL. They took ages to arrive from china so Order these early on. The only supplier i found is linked here and they weren't really cheap considering.(eBay Search term = 26 Letters A-Z Blue Led Dia 10mm Cap 12V Momentary Tact Push Button Switch)

These switches contain a built in LED which will run up to 3 volts. I misread the descripotion on the sale and understood 12v butb that was the switch rating not the LED. This was an small issue later as I couldnít simply wire it to the mains adapter as that was 6 volts and the first time i tried i burnt out the LED in seconds. Instead I used my meter to search around the main board and found about 2.7 volts i think it was, on the blue capacitor highlighted.


I then ran a pair of wires and linked all the function button LEDís in parallel. This meant that the function lights remain lit while the game is in operation.

KIT thinking light


The last step was to add a thinking KIT light to the top of the board/ I wanted to replace the thinking LED with something a little more fun, I drilled 2 mm holes in a line in the top part of the frame and then from the rear of the frame I drilled a 4mm hole about 5 mm deep.

You may want to use a felt tip marker to touch up any exposed white wood from the drilling process before proceeding I then fed a 2mm fibre optic wire into the 2mm hole from the front and from the rear I pushed in the 3mm flat head blue led until the optic fibre butted up against the LED, slightly extract the Optic fibre again and snip off and push flush.

Larson Scanner KIT available here


The LEDS are then attached to the kit board I purchased here. This comes with a complete wiring diagram that you should find simple to assemble. I assembled it as per the instructions and with the original LEDs that came with it first, just to test it and see it in action. I then removed the KITs LEDs and replaced it with my blue ones. You might want to run wires to yours but I manged to actually mod mine directly from the board into the new holes in the back of the frame. More by luck than anything else I had drilled my holes in the frame almost exactly the same distamce apart as the LED's on the kit board.
A confession, I actually made a mistake here and drilled 10 holes for the LEDs in the frame, for some weird reason i had thought the KIT board had 10 LED's but in fact it only has 8. You can see in the pic below how I solved the issue. I tacked on an extra LED in parrallel on each end.


Test the circuit with your coin cell battery again to make sure itís working and then when youíre happy attach it in place of the ďThinking LEDĒ . All you do is run the two wires from the Thinking LED to the power input of the KIT board. Pos to pos and Neg to Neg. Simple heh. Now every time the computer thinks it wonít just light up a boring LED but it will give you the KIT effect.

You should have by now attached the mains adapter and tested the board.MAKE SURE THE SWITCH IS MOVED TO THE BATTERY SETTING!




Hopefully you can play a game on a flat surface to make sure everything is running as planned.If you have a depressed switch somewhere the board will light up odd LEDs, donít worry too much, I had quite a few issues with the switches when I attempted this with wood veneer. Thatís why I eventually scrapped the veneer approach and switched to leather. Use your meter and follow each buttons path to find the fault. The faulty path will be along the route of the error lit LED

If you have got this far and all is working, Congratulations!! I know itís a lot of work but from here on it gets easier.
Tidy up and secure all your wiring as much as possible. And turn the board over so that you looking at the leather front,
Itís time to frame!!

By now you should have purchased a frame suitable for your creation. The frame is the big difference in making this look great or just Meh. The frames I use are about 70 euro each so a big part of the project cost is the frame. Take care with it and insert you board. This is where your overlapping leather squares pay off as youíll see everything looks lovely and thereís no exposed board anywhere. The visible squares should all be the same size! Pin the board in place with thos little wedge staples you see in most paintings, failing that tap some small tac nails in at at angle to hold the board in place while you work on.

Shelves


The shelves are 6mm thick by 400mm long and 30 mm deep. I chose them this thickness because I initially intended to drill holes into the edge of them and feed the LEDs through to the front of them. This idea changed but because they were thick enough i was able to drill 3mm holes into the edge of them. Drill 3mm holes into the edge and about 2/3rds of the way through. Donít go all the way through!

This was made easy by using a bench press drill but you could do it by hand if you are very very careful. I lined up the shelves on the board and marked off where the holes Between squares 1 and 2 and between square 7 and 8, were needed, these are along these are in the 5mm gaps remember?)







Take time and care to make sure you line these up exactly!! You could ruin the whole project here so Seriously, do line the holes up exactly. How I actually lined them up was to insert a spare pin in each side of the shelf I was affixing. The pins I had sharpened down so basically they were pointed. I then position them on the board and then pressed so that they marked the spots where I needed to drill my holes. Remove the pins and repeat on the next shelf. Don't just use the same shelf to mark all the holes, because they are bound to have differences.

Once I had these lined up properly I searched the shed for some 3mm wire. I ended up breaking apart an old bathroom shelf thing, you know the sort, wiry thing where you put all your shampoos etc, the ones that are stainless steel and rust after a month.



Well It turned out to be the perfect diameter so I cut a couple of lengths off it and then cut them into little steel pins about 25mm long. They donít have to be exact as they will extend out of the back of the board which wonít be seen but they do need to be long enough to go through the 6mm board.

Feed one of the pins into the glass shelf and tap it in until it butts up to the end. This should leave you with about a 15mm of exposed pin to feed into the corresponding hole on the board.

If you have lined up your holes then the shelves will all slot into place and sit firmly against the board. Once you have done this for all the shelves you should now have perfectly level and steady shelves stretching exactly across the board beneath every row. Now stand up your frame and switch it on and give it a test run
Once everything is running satisfactory then itís time to finish the project up.

You may notice that the wiring and main board of the computer are protruding out of the back of the frame, I added a one inch frame to the back of the purchased frame and matched the colour as best I could. You will need a Mitre block and saw to do this but you should be fine.Also added a couple fo inner blocks of wood to attach the wall hangars.













Power


I used a 8v adapter i found in the shed, I think it's an old mobile phone charger, just not sure.You can see the specs in the photo here.It would naturally be a bonus if you manage to get a computer where the seller includes the adapter. Cut the plug of the end and wire it via your power switch directly to the dc inpout jack on the main board.



A final word on power switch. I used a 12mm on/off latch switch with built in Blue led.
It took me a while to figure out the wiring on the thing so that it lit as well as switched on but eventually you'll get it. Just solder some wires to the pins and experiment with your coin cell and meter til you find the right combination.







I mounted the set and added a lamp above and a small glass shelf below for the captured pieces.







Wrap up


I've built a few things over the last few years as a hobby. I have a Bartop Mame Arcade Machine,



A wall mounted Touchscreen Jukebox



And now my wall mounted electronic Chess.

I would love to hear from other people who attempt this kind of mod or indeed any other suggestions regarding future projects along these lines. If you'd like to contact me regarding this project, please do so through this email address.

artlessdodger@wallchess.co.uk

Best Regards

Artless_Dodger - April 2014