OT: Light lubricant

Keycaps are made from either ABS or PBT. PBT is more durable. The easiest way to tell the difference is that ABS will be destroyed by acetone, while PBT is more resistant.

"How to lube your switches"

I don't lube my keyboards because the grease tends to make the dirt, dust and food debris stick to the grease, which then requires disassembly to repair. By the time the sliding parts of the keys have gouged the walls of the key, no amount of lubrication will return the key to normal operation.

Also, grease tends to cause intermittent contact closures. If the key has exposed contacts, you might try dielectric grease. I haven't tried it, but I think it might work.

Thanks for the reply. I'll look for something similar in my country. And no, I won't blame you if it blows up my keyboard :-) (I'm sure it won't). It's a $30 kb+mouse combo and I've already had 2.5 yrs of service out of it. It's still going strong - I live in a dusty environment and just felt like giving it a thorough cleaning.

Anyway, I was looking more for a general-purpose lubricant than for one specifically for a keyboard.

It's the same grease used in cameras. You can buy small cups of it from Amazon, search camera grease.

Cheers

Graphite is conductive, which is that last thing I would want inside an electrical switch.

It's called "membrane keyboard lube". There are many sources. But as Jeff L notes, the keyboard may already be toast. But you have noting to lose then.

Joe

There is no "application". Mr Pimpom is just trying to clean his keyboard and not design a product around it. He mentioned that he was working on a "membrane-type" keyboard, not a mechanical keyboard: "when I disassembled my Logitech membrane-type keyboard" I believe you might be thinking of a mechanical keyboard. Whether the keyboard is membrane or mechanical, dumping conductive grease into the contact area is a really bad idea.

Membrane keyboards have a silicone rubber sheet with a dome shaped protrusion forming the spring and actuator or the switch. Below the dome are 2 PCB (printed circuit board) traces, which are the switch contacts. When the dome is depressed by the users finger, the conductive graphite paint coating the inside of the dome bridges these two PCB traces, which the key matrix decoder recognizes as a key press.

Adding additional graphite lube to the switch will eventually short out the switch. The silicone rubber sheet does NOT act as a protective seal. The graphite lubricant, which is usually mixed with oil or grease, will eventually find it's way under the dome by capillary action (especially at the PCB edges) or through cracks as the flexible silicone rubber sheet cracks with age.