I was wondering how you can clean old #44 or #47 lamp sockets from early Solid state playfield. Replacing these numerous lamp sockets can be a very expensive proposition with sockets price going up to $2 each or more and I was wondering if anybody had experimented with some technique to restore them to good electrical contacts.

I was thinking about three solutions:

1) Tumbling them with corn or nuts, but that will entail a very deep and thorough cleaning afterwards, as the corn will remain stuck inside the socket. I also suspect that not much rubbing will occur inside.

2) A bath in Evapo-rust.

3) A tedious sanding inside and outside of each socket with abrasive stick and sanding paper.

Any idea and recipe would be more than welcome.
Thanks
Yves

Thank you all for the very good information.

To answer Rolf, ideally I would love to clean the sockets as I wash my car (double buckets, Orbital buffer, Meguiars 105/205, Collinite 845 Sealant) but let's be more realistic and BBB is probably plenty enough. I was trying to find a way in between AAA and BBB without having to buy a large number of expensive sockets.

I currently use the PBR stick and it works most of the times, although the sockets do not look too good.
I think the soldering of the base nipple is key to reliable working.

Yves