polishing pins of NOS tubes

I hope by ’corroded’ you mean ’tarnished’.

If that is what you mean, a small strip of metal cleaning/polishing cloth should work, followed by a cleaning with 91%+ alcohol.

Loop the cloth around a pin, pinch it with tweezers, and clean with an up and down motion. When nice and shiny (untarnished looking), pour the alcohol into its bottle cap or a bowl to pin depth and stick the pins in it. let it sit in it a bit, then take it out, dip the tip of a paper towel in, and repeat the tweezer thing, finishing with a dry paper towel.

A Dremel tool I think is best, get a polishing attachment and you won't have to go through all of the above!

I've used a Dremel many times to clean up tube pins, it's not difficult at all as long as you pay attention to the direction of tool rotation and use it correctly. I use Maas metal polish on a small felt wheel as opposed to the brass brush though. Even if a pin gets bent a little, a quick tweak with a pair of needle nose pliers gets them back in order. Then clean the residue off with alcohol like the previous post describes. I also have used the exact same procedure described above with the exception of using very fine grit  wet or dry sandpaper strips cut 1/4" wide instead of a polishing cloth. Usually 1000 grit works fine. 

Don't worry about it, use the steel brush on the steel pins. If you come across copper or brass pins, use the corresponding brush. After brushing, wipe off the pins with an alcohol swab.

I've used Deoxit with great results.

If that is what you mean, a small strip of metal cleaning/polishing cloth should work, followed by a cleaning with 91%+ alcohol.

+1

If the tubes are small signal tubes, take care cleaning the pins if gold plated.

FYI, I remember reading a thread years ago on AA about the steel pins on small signal tubes. Someone posted saying, the pins are not actually made of steel. Darned, if I can remember what it is though.

The reason given for not being steel. Steel will expand when heated. Not good when the tube is made of glass.

EDIT:

Quick search on the Net.

The metal pins on small signal vacuum tubes, also known as lead-out wires, are typically made of a ferrous metal, and the seals through the glass are made of a copper alloy called dumet..

"Dumet" refers to a glass-to-metal sealing alloy, specifically a bimetal made of a nickel-iron core encased in an oxygen-free-high-conductivity (OFHC) copper sheath, used for creating vacuum-tight seals in applications like lamps, diodes, and capacitor slug leads.

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I’ll check the pins with a magnet...