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Full Version: Lubing slide switches on LED models? (Spice, Woodstock, Classic, etc.)
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LED-model gurus --

I have three HP-34C's upon which I am doing some minor repairs, including lubricating the ON/OFF and PRGM/RUN slide switches. The switches carry metal spring jumpers that span two broken parallel circuit "tracks" (for want of the proper term) when the switches are moved to the right. I noticed a pasty yellow(ed) residue of the original lubricant on one unit, but often there is little lube left, and the switches slide roughly. (Good thing the HP-41C and Voayger models did away with them for good!)

What would be good lubricant for these switches? I have bought a thick, clear "Lube Gel" from Radio Shack (p/n 64-2326) which is conductive enough to work just fine on the sliding ring connection for my car's horn. Does anyone have a better idea?


-- Karl

I don't think you would want anything that conducts because it may get into places you don't want and short tracks that you don't want connected. This would drain the batteries or stop the calculator working. I think the idea of the lubricant is to stop the contacts and tracks wearing - you still need good metal to metal contact.

At work we once had an outside service 'engineer' come in to fit a new PC processor. He got the heat sink grease (which also conducts electricity) onto, and into, the ZIF socket. The PC would not work after this and because the heat conduting grease could not be cleaned out of the ZIF socket the whole PC mother board had to be replaced - luckily not at our expense.

For what it's worth, in June of 2000 I lubricated the
switches on my HP-67 with a small amount of Permatex
Silicone Dielectric Grease, purchased at an auto supply store. As you know, a dielectric is an insulator. Everything still works fine.

For those contacts, I use a "Lubriplate" by GC Electronics (you can get it from MCM and lots more places, I'm sure). It's specifically made for lubricating switches, motor bearings, etc..

Radio Shack Lube Gel is surprisingly good stuff. Also Permatex SuperLube or Dow Corning 111.