IBM model M has 5 keys that do not work. How can I clean those contacts in the membranes?

The keyboard is in excellent shape otherwise.  Can I puncture the bottom metal shell in the locations in trouble and then inject contact cleaner?  Are there some other vent holes that might be used?  Could it be an electonic problem or circuit board plating in those areas?  The five keys affected are :
g,  h,    apostophe ,   up arow,  and the number pad zero.

rogets (author) 7 years ago
Thanks for the answers.  Looks like the dust under the keys might be th problem.  I will investigate further.  I am hung up on the membrane idea.  If I may I would like to send you these links.  In the meantime I will look harder around the keys to see if anything is holding them up.


lemonie7 years ago
Was something spilled on it?
Injecting cleaner is not likely to work, it'll need to be disassembled and inspected before anything else.

orksecurity7 years ago
The model M isn't a membrane keyboard. See https://www.instructables.com/id/Clean_your_vintage_IBM_M2_clicky_keyboard/ for one approach to disassembling and reassembling it.

Note that quite often, the problem is just something caught under the key, or a key that wasn't reassembled properly.  You usually don't have to disassemble unless it has been pretty seriously abused.