Identifying the dampening foam used in keyboards
Identifying the dampening foam used in keyboards
I discovered this 4mm thick foam in my room that might suit my HyperX Alloy Origins, but I'm uncertain about its type or suitability. I'm sure if the material isn't conductive, it would be appropriate. The foam appears firm, slightly rigid, and has a smooth surface with minimal pores. Does anyone recognize this material? Would it be effective for dampening purposes?
Seems like styrofoam but without the usual small pellets. Do tiny round fragments detach and then cling electrostatically to surfaces? The pad makes a slight squeak or crunch when gently bent.
How do you intend to use this foam: perhaps as a pad under the whole keyboard? I don’t see any damage, so I’m willing to try it. Maybe it could help reduce noise.
Yes, if it were EVA foam it would not be conductive and would be suitable for use.
It's quite gentle when pressed, producing only soft sounds. It appears to be made of foam, though I'm unsure of its exact composition and whether it's safe for use as a keyboard dampener. To confirm if it's non-conductive and suitable for your setup, you'll need to test it.
Do you know the origin of the foam?
There are non-electrostatic materials available for packaging electronics.
For instance:
https://www.amazon.com/Multicomp-Density...B071G74PGW
You can easily search for other similar products and details.
It’s unlikely the foam is electrically conductive. But it might gather extra electrons, leading to a spark when they reach a path to ground or earth—possibly through the base plate, PCB, and cord.
Gently rub the foam; try it on a dry cloth or a rug. See if rubbing causes a buildup of electrons.
If this happens, the foam may attract small particles like paper or hair, sticking to surfaces as with an electrostatically charged balloon.
Sparks can also appear in similar situations, especially in drier conditions.
The outcome might depend on the surface it rests on: metal, wood, glass, plastic.
If no excess electrons accumulate, everything should be fine.
EVA foam is frequently employed in electronic packaging, though it is typically enhanced with metal to ensure ESD safety. It wouldn't be a major concern in a keyboard or key cap because it stays connected to a grounded surface (unless the device is wireless).
The keyboard being wired and placed on a wooden table means it's already connected to the ground through the wiring and the table provides a stable base.
In reality, the opposite is true. The ground or neutral connection is connected back through the power supply chassis into the wall, effectively reaching the earth. Most homes feature a metal rod driven into the ground. Your USB ports and keyboard cables are also grounded internally, while your keyboard typically has a metal or plastic surface linked to the neutral at some point. Consumer electronics often incorporate metal compounds during injection molding to allow the plastic to conduct current and maintain contact with the ground. This design reduces danger if the keyboard gets wet, as the current would simply flow to the ground instead of passing through your body. The metal also helps block unwanted signals from devices, making them EMI resistant.
Being ESD safe is simple—it means the surface must be conductive so any potential difference is quickly neutralized. The dark coating on common anti-static bags is usually a metal layer, and some pink or blue options may have metal paint. ESD wrist straps consist of a wire wrapped around your wrist that connects to a grounded surface.
On the positive side, many foams and plastics naturally contain metal, not just intentionally, but also as part of their production process. Many polymers are processed with metal catalysts, such as in PVC, which includes a small amount of copper—explaining its safety for drinking water due to residual antimicrobial properties. Nickel is also frequently used, alongside titanium in very white plastics.
Wooden tables provide good insulation, allowing for potential differences, but many wood surfaces also hold moisture, making them less problematic. Since your computer is properly grounded, this remains a safe situation.
It would be helpful if the foam could conduct electricity to prevent ESD issues. I wondered if adding metal would make it worse. Should the foam have higher conductivity or be less likely to cause static discharge?