Having made many hundreds of salt mills during my career, had a few back for repair, considered writing some good maintenance information but backed off due to the possible complexity of the subject.
Today I found myself, a user, with a clogged up salt mill that was not functioning due to the salt crystals becoming damp at some stage. Having cured the problem relatively easily I now feel able to write the following simple maintenance procedure.
1) Remove salt mill knob and cap and empty salt crystals into the rubbish bin (do not be tempted to reuse)
2) In a glass measuring jug fill to the 1pt level and heat to 60 degrees centigrade. Immerse mill body, cap and knob fully for a few minutes until remaining salt crystals have dissolved. Holding the grinder spindle and dunking up and down will speed up this process.
3) Remove mill parts from the jug and discard the liquid
4) Repeat 2 and 3
5) Repeat 2 and 3
6) Drain and dry thoroughly inside and out using kitchen paper (cap drains better upside down) and place overnight, upside down on a warm surface covered again with kitchen paper. A central heating boiler or radiator will be adequate. Any hotter will burn or melt the perspex base.
7) Re assemble and polish using Silvo or similar product. Refill with fresh salt crystals.
Important!!!! There must not be and never be any water present in any parts of the mill as this will immediately create a problem and serious damage.
Enjoy the experience of using silver for good food and dining, as we do, everyday.