On such jobs I use a smidgin of grease or, preferably, way oil on the swivel joints along with their location faces but make sure the actual clamping surfaces are clean and dry.
Way oil is preferable to grease because its easier to wipe just enough on for a thin, sliding layer and remove the excess. Grease tends to be abit thick and clumpy.
Way oil rather than ordinary oil because the takifiers help it stay put and the blend is intended to hang around at room temperature for long periods. Automotive oils are blended to work at engine temepratures and have additives which tend to promote varnishing over long periods at room temperature. The water / condensation removal ones being the usual culprit. Household "handy oils" usually have wicking / penetration additives which mean the stuff tends not to stay put!
Clive