I've been playing FPS games on my PC for a while now and I frequently found myself in need of more buttons on my mouse.That's why I bought at one time a Logitech G9,but in some games even the buttons on it's extra 4 ones seemed to be few.At some point later I purchased another mouse with more buttons but I sadly realized that it wasn't fitting to my claw/hybrid claw style grip which resulted in messing up my aim.In my country's market (Greece) finding a mouse that will absolutely match your needs,with the non-existant shop return policies,seems pretty impossible.It is more possible to end up having bought an expensive mouse which will not fulfill the purpose it was bought for.There is a board on ebay which is basically a virtual keyboard on which you hook up switches that costs about 50€ and is much more versatile and compact but it costs 50€ more than the old keyboard I have around :) (or half as much as buying a MMO mouse) and since the PC doesn't mind having 2 keyboards connected to it...
So after some thinking and getting inspired by other instructables I decided to add buttons to my g9 mouse.
Step 1: Needed Materials
I'd like to start with my apologies for any language or terminology mistakes I will make.I hope that at least I will be understandable... :)
For this project you're going to need to be able to do some soldering and plenty of time since it's kind off delicate work,at least for my level of soldering skills.
1) a usb keyboard (non mechanical), 2) the soon to be enhanced mouse, 3) some IDE cable strips, 4) pcb buttons (number and kind of depends on personal preference-I went for 4), 5) some of the wires that connect PC case switches and led's to the motherboard, 6) one of the connector receiver plugs (?) the IDE hooks on the motherboard, 7) some electric wire - ideally with 4 different colours
As for tools you will need a soldering iron (and assorted items), a hot glue gun, a small hacksaw, a multimeter, double sided tape, electrical and masking tape, a circuit board holder with crocodile clamps and some precision tweezers and small pair of scissors will make this much easier.The wires on the IDE cable strips I had were consisted of a material that wasn't attaching to my solder and basically I had to trap it between the other cable and solder
Step 2: Assemble the Wire That Will Go in the Keyboard
Take one of the IDE cables,take off the plastic connectors at end and middle and with the scissors carefully cut it so 4 (depends on your project again) pairs of cables get separated from the strip.Repeat this once more and after you solder the two small strips you removed from the main one on each wire you will end up with 8 wires attached to each other with double the length of the original IDE cable.Hot glue or wrap it with electrical tape making sure that the naked wires don't touch each other.No need for it to be pretty since it will most likely be out of sight.Place some electrical tape on the point where the middle connector used to puncture the IDE cable,just in case.
It is very important that whenever soldering joints are made,always remember to check with your multimeter for proper soldering connection and avoidance of shortcircuit.Removing electrical tape or ever worse hot glue from a soldering point to repair it is very time consuming and troublesome.
After the two parts are properly connected,cut 4 pairs of different coloured wire that you should probably have lying around and solder it accordingly to your new thin cable.The point of this is having a thicker wire with more threads making contact with the points inside the keyboard.Each wire pair coming from your custom IDE cable should be soldered to a specific colour of wire (to avoid mixups).Insulate each solder joint but don't tape them all together yet.
On the other end of your IDE cable solder each wire to the pcb part of the connector receiver plug,making parallel pairs; the first two wires to the first pair of the connector and then following on.Following this (or any) method will save you time on the end.To specify the length of each pair you will add you should take in mind the entry point of the cables on the keyboard and the position/of the keys you will interfere with,but you shouldn't cut the other end of these extra wires until you reach the appropriate point on step 3.When this is done take your hacksaw and cut the remaining part of the connector to keep it small and light.I kept an extra pair of pins just in case.Cover the solder joints with hot glue to stabilize it and keep it shortcircuit free.Make a last check with your multimeter to make sure everything went OK as in each wire making contact to and only the corresponding one on the other end.
Step 3: Work on the Keyboard
Take apart the keyboard and basically follow this or any similar instructable.Drill or cut some holes for the wiring to go through. You basically stick on top and bottom layer each end of every pair of the custom cable.I opted to set up keyboard keys 8,9,0 and + (the numpad one).Since all the contact will not be stabilized by soldering you should scratch the contact points on the layers inside the keyboard to take off some of the semiconducting layer that they are covered with.No need to make the connections thin(the silicone should absorb any extra volume);the only thing that (since the electrical tape adhesive probably will wear out eventually) will ensure electric current flow from wire to keyboard contact is pressure.Actually I added some foam pads (used to protect electronic item within its package) held right on top of contact points with electrical tape to ensure that contact was made, since otherwise this was not happening consistently. 0,7-1cm should be enough depending on thickness of foam- mine was quite thick.At this point proper contact probably will not be made always but with addition of the pressure by the foam after the keyboard is assembled again it should be just fine.
Before you do that though,you should check the connections.With EXTREME CAUTION to not touch any naked wire or control board inside the keyboard (don't worry about the back side of top layer which faces because it is insulated) plug the keyboard in any computer,open a program like Notepad.I don't think that there is strong enough current in a keyboard but you should make sure you don't find out ;).Pick up an INSULATED grip screwdriver or some similar insulated tool and short circuit each pair of pins at a time at the other end of your cable on the IDE pcb connector.Some pressure on top of the top keyboard layer may be needed,but if everything went OK you should see the Notepad writing up a key you specified inside the keyboard-in my case strings of 8's,9's,0's and +'s.If this is done with none to something to more than low pressure on the contact spot you should be fine,so take a note which key corresponds to which cable colour and then assemble the keyboard.
Use some hot glue on the point the wires entry the keyboard to stabilize them.Furthermore stabilize your wire to the first 10 cm's of your keyboard's usb cable by wrapping it with some electrical,masking or packing tape so if for some reason it gets pulled it will not get disconnected.
Step 4: Assemble the Wire That Will Be Connected to the Mouse
For this one you should do the same things you did for the to-the-keyboard wire except that instead of connecting the IDE pcb connector on one end,you solder the wires to the small wires that connect PC case switches and led's to the motherboard.Those will end up being pluged on the keyboard's IDE pcb connector so you are able to deattach the mouse from the keyboard whenever you want to.For this one I used a black IDE cable strip that was lighter and thinner than the other one thus having less volume and weight on the mouse and the mouse cable plus it looks better than the eggshell one.Don't forget to check again with the multimeter when you are done
Step 5: Work on the Mouse
Probably you must have done this before you go through the entire thing ;). Take some electronic switches,what you will choose is up to personal preference,number of buttons needed and mouse grip style.Stick them on your mouse with some double sided tape on locations that you will be able to press them easily with not much strength requirement.You possibly will have to experiment a bit to see if and which position it really accommodates you since those switches aren't as comfortable or ergonomic as the factory ones that are found on high end mice.I decided to go for three press button ones on my thumb plus one lever for my middle finger.After you pick the final spot set them there steady.If you regret later you can change position again.The 3 switches while unpressed would allow current from points 1 to 3 and 2 to 4 but when pressed the current goes anywhere so in each I cut the one pair positioned on the same side and set the other one heading to the mouse's forward side.For the specific switches the custom wire should only be stripped for just a couple millimeters.
Take your black IDE cable and place it on the mouse so it runs the edge of the thumb side until it reaches the last button spot.Do this so you find the point where you split the wire to 3 pairs on one way while the last one which will go on the other side.The split should just take a pair of wires out of your way for now but eventually will be right until the mouse usb cable,on which it will also be taped later on.Start soldering pair by pair the wires to the switches.You will most likely need to cut the wires that are headed to the front most switches.Be extra careful in this step because any mistake you make in this point will be always right in your face :). Cable pair to switch pairing isn't important as you will choose later which one will be which by connecting the pins whichever way you like to.You should try to position the cable in a way that is as much tighter to the mouse's body and is not overlapping;it is going to be one ugly a** mouse anyway,no need to make it worse or uncomfortable ;).Once again you should check for current flow from each switch to the other end of the cable before continuing on to the next switch.After you do that hot glue the naked wire points to insulate them.
Once the three pairs are soldered,"hug" the mouses side with the cable as you head towards the usb cable and stick it with double sided tape so it will not extrude.Make sure the before mentioned split is right on point where the usb cable connects to the mouse and afterwards go ahead and solder the remaining wire pair to the final switch.
Use some electrical tape to tape the IDE cable to the usb cable for 20-30cm or whichever length suits your desk arrangement.
Step 6: Final Assembly
By now you should have a keyboard that has a wire with an IDE pcb connector with male pins on the end and a mouse with a similar wire with female connectors on its other end.Connect the keyboard's wire IDE connector pins (you remembered to take note which one goes where earlier,right?) to the the desired mouse's IDE cable.Plug the keyboard in your PC and if everything went to plan, when you press a specific button on your mouse it will be as if you were pressing a specific keyboard key.Arrange the wires and put the keyboard somewhere out off sight (the keys you messed around with won't be working if are pressed so you won't have much use for it anyway) and enjoy your... old and improved mouse :)
Step 7: Final Thoughts
For this project you could also use one of those add to laptop numpad small keyboards to save some space.Also,having a simple mouse with flat left side could be used to add 6+ switches and make a MMO mouse (back in the day playing WOW PvP with a rogue was impossible for me because in order to attack I had to stop moving) for a fraction of the cost the popular MMO ones cost (provided you have the other items lying around).
This website has given me so much inspiration and ideas and I sincerely hope this first instructable of mine will be found useful.Take care