Hi folks,

I have an old darkroom lamp from the 1960s. It originally had a red bulb to protect the black-and-white film. I like the style, so I'm converting it into a desk lamp.

It has a pair of ball-and-socket joints in the arm (ball is about 1/2" diameter, and the power cable passes through the centre). The joint is held stiff by an internal compression spring, but this isn't quite providing enough friction.

I had wondered about fitting a stiffer spring, or trying to stretch the spring a little, but I'm not sure how easy or wise this is.

I'm now thinking of squirting some tip grip liquid for screwdriver bits into the joints instead. Something like this:

https://www.amazon.com/-/de/Vibra-TI...dp/B008RMT63A/

Does anyone know what's in this liquid? Is it carborundum, or something like that, which might cause serious joint wear?

The joints are made from hard brass.

Thanks!

Best wishes,

Chris