Self made foam dampening - a lessons learned on how to love up hotswap sockets

Part 1


I was wondering… being the lumpy, lazy, cheap, person that I am… could I make myself some own PCB foam dampening? You know, cheap and efficiently? Cutting foam rubber in the right places to be seated between the plate and PCB? Turns out I can.
So I did.
It creates a little bit of strain on the switches and it feels like this also increases the tension on the stabilizers, even though the stabilizer bodies as well as the wires do not come in contact with the foam. This moved the acoustic profile towards a more saturated and richer nuance.

The thickness is 2mm and as you can see by the pressure marks it puts strain on the pcb and the plate by pushing up the switch.

But there is room left between the foam and the plate. However I went with this setup for two months trying the RK brown switches (“tactile”), the epsilons (linear) and the Box Jades (“orgasmic awesome tripple power god like clickys”).

On the backspace I needed to remove it since somehow it prevented the stabilizer from rising. It is one of some factors that has a negative impact them.

I’ve left the case hollow since I don’t want to increase the POTENTIAL heating of the battery any more than I already did with the foam. Since my current desk is actually my wifes old kitchen table and about 90 to 100 yrs. old.

Setup: Plate, Foam, PCB


2nd Part

This setup worked fine and I removed and replaced the switches several times. Some pins were bent but straigten them up and reseating the switches always worked fine. Now I know that it is suggested not to use a whole sheet of foam or similar since it makes it much easier to bend the pins or uncontrollably damage the hot swap sockets. But I believed I was thorough and careful enough… oh what a misperception. But more on that later.

So, after two months I was checking and cleaning again the keys when it hit me. The gap between the foam and the plate can be closed by another layer of the foam. So the dcision was made to fill it up. I knew I need to make cutouts for the switches since the first layer was putting up tension enough on them.

I used different colours since the fine permanent marker from Edding I use was well hidden in our garden at the time.

Cut them all out with a scalpel, yes sir. Did it!

I had to settle on non-water-resistant fineliner.

Needless to say the cutouts for the stabilizers and their wires have to be made generously to prevent dozens of tries to fine tune them and expanding small but neat cut outs.

Put both layers in place

And the gap is closed.

Test the stabilizers…

… aaand…


3rd Part

-= this one has no photos as I can only remember that night as part of a feverish nightmare. With salty, salty, tears in my eyes =-

  1. Inserted all the switches for about the 6th time of the short lifespan of the RK84
  2. Bent about 12 pins back in shape and straightened them up
  3. Found still 2 keys not working (F8 and 8)
  4. Found the LEDs for the column with F8, 8, I, K, Comma, and Option keys completely failing
  5. Found the hotswap socket of the 8 key to be loose on one side
  6. Spent about 30 minutes trying to resolder the socket
  7. Spent about 1 hr looking for flux
  8. Spent about 2 hrs trying to resolder the loose socket joint
  9. Spent about 10 minutes swearing because I burnt the pcb and because solder would only stick to the soldering iron and the metal contact on the socket BUT NOT on the copper contact below the socket
  10. Spent some more minutes of finding more creative curse words since the copper wiring on the pcb was ripped out for about 3 mm in length alongside the solder joint.
  11. Put some more solder on it and finally had it stick to the pcb for once
  12. Tested the socket w/o switch → worked
  13. Tested the socket with switch → failed
  14. Unscrewd plate and pcb for the 6th time this evening
  15. Did some more soldering with the switch already plugged in the pcb
  16. Used hot glue to keep the pressure on the again and again detaching solder joint
  17. Cleaned the plate and pcb from tears and sweat of anger and punishment
  18. Cried
  19. Cried some more
  20. Screwed everyting back together
  21. Contacted RK support if they’ll sell me a replacement pcb
  22. Started to hate the part of my life that is our hobby

Ok, went back to the crime scene to take some pictures if the victim.

Profile of the perpetrator: plain idiot.


Lovely :heart:

Thank you for your detailed process and sharing.


I’ve done this once and you’re absolutely the opposite of lazy for taking this one. It’s slow, tedious work to make your own plate foam. Did you have the PCB lying on your working surface when you were reinserting all of the switches or was it installed in the case?


Thank you for the kind words. Of course I had plate and PCB seated in the case. It’s only after you make an error, you learn. Isn’t it? Not in advance. From now on I will always administer counter pressure with the other hand onto the sockets towards the switch. Big promise. :slight_smile:


make friends with someone that owns a cricut; save 10 hours of work


Ok. Some dude on reddit read my story and told me to use wire since I couldn’t be able to repair the broke copper lane from the hot swap socket. So I gave it a shot.

When I was removing the blob of solder that I have left there previously, the mother loving hot swap socket stuck again to the PCB all of a sudde. Within seconds of accidental treatment… Don’t know why. :expressionless: But the F8 still wouldn’t register when manually bridging them and the former loose 8 key was still registering only when I manually bridged both pins from the bottom. So no key press register when actuating the switch.
I went on and soldered the red and black wire as pictured (or depicted???) above and suddenly everything worked again.
8 key bridging :white_check_mark:
F8 key bridging :white_check_mark:
8 key key stroke registering :white_check_mark:
F8 key key stroke registering :white_check_mark:
Led column :white_check_mark:

I’m not very religious and I certainly don’t want to offend anyone but… thank you happy easter bunny god. I’ll praise your name on this shiny sunday afternoon. My little, beloved, productive, clickitty-clackitty, thingy is working again as specified.