Cherry conversion
1. RequirementsYou need to buy the following parts:
- Custom PCB [
link]
OSHpark is probably the easiest place to order these, but it is not cheap for this size boards ($47.80). I ordered mine from china for under 20€ / 5 pieces. I can give gerber files and info about the shops if you want.
- 3D printed frame [
link]
If you have a 3d printer you can try to print these yourself. However I highly recommend you to not do it. These were not designed to be printed with filament printer. I ordered mine from i.materialise.com. Printed as polyamide and dyed black. All the dimensions seem to match, so I can recommend this to others.
- x14 Cherry MX switches.
The switch type whatever you like.
- x14 Diodes.
Pretty much any basic through hole diode like 1N4148 will work. I accidentally used zener diodes, don't do that yourself...
- (optional) x14 3mm LEDs.
Any color you like. Check the current and voltage ratings for the leds. You will need those to calculate the correct resistors for those.
- (optional) x14 resistors for the leds.
Use some resistor calculation tool to calculate the correct resistors (like this:
http://ledcalc.com/). The supply voltage is 5V and the leds are connected parallel.
2. Open the N52te and remove the key boardThere are screws on the back. One is under the thumb key rubber pad and another one is under joystick rubber pad. The rest are visible without removing anything extra.
Desolder the 10 wire ribbon cable that goes to the keypad pcb. After all this you should get this part off of the device:
NOTE: do not cut the ribbon cable like I did. You need it full length.You got it? Good, now trow it away, because we are going to replace it.
3. Solder the diodes (and resistors)Solder the diodes and resistors to the pcb. If you dont need the diodes, then dont solder the resistors. There are markings on the board. If you are in doubt, check the pic.
Important note: The legs of the components can not be longer than 1mm on the front side of the board. Otherwise those will hit the frame.
4. Trim the printed frameYou can skip this step if you ordered the parts separately.I have made a version where the frame and bottom parts are connected with struts. This is because usually there is a minimum price for a single print. This makes it cheaper to print.
The struts are in red on the render:
5. Place switchesThe switches are installed "upside down". Meaning the leds are on the top. If the holes are too small, use a file. Holes on my print were prefect size.
6. Combine these two parts togetherYou should be able to fit these 2 together now. Make sure you press these together completely. If you didn't trim the legs of the resistors and diodes short enough, this is the part where it will be a problem.
7. Add ledsNext put 3mm leds to the switches. Cathode is on the right side, which I guess is also the opposite to the regular way. The max length for the legs is 2mm here.
8. Solder the ribbon cableAfter these steps you should have something like this:
Make sure it fits inside the device before soldering the ribbon cable.
Next you need to solder the ribbon cable to the pcb. It is attached the same way as on the original board.
NOTE: On the picture the pads are through hole, but on the design I will give those are SMD pads on the backside. These are in my opinion easier to solder.Here are pics of my tests:
9. Close up the deviceNow you should be able to close the device. Polyamide is quite flexible, so you may need to press the case parts a little to get everything fit.
