This week has seen me struggling with one of those wargames horror stories....the dreaded lead rot!
As part of the sidetrack into F&I war (solidified by a re-read of Parkman) saw me acquire rather a lot of old Pax Britannica / RSM nominally 30mm French and British figures. The price was right but marred by the discovery that many of the figures were slightly showing discoloration and patches of white powdering. Some of the figures felt rough where the colour was different.
After some research, it appears the white patches are lead carbonate, in effect lead rust and are signs of a reaction of the metal to certain storage conditions, especially damp, humid areas with both wood and cardboard producing the necessary acids to create the reaction. It seems however, not even plastic storage containers are immune from producing acids.
There followed some fairly extensive research on the internet on the phenomenon. Frankly, much of it was nonsense; everyone it seems has an opinion, some solutions appear more akin to voodoo or quackery!
Many were accompanied by horrific pictures of miniatures sprouting growths like something out of a horror show or medical textbook......
Fortunately, my miniatures were not so badly effected (no pictures as the camera on my tablet wouldn't focus enough); while I could have simply returned them, the figures are now difficult to obtain, so I have been looking at solutions.
The suggestions vary from throw them away or quarantine them (no evidence it's actually contagious) to chemical or physical removal of offending material. The commonest solution being one from The Game of Thrones author involving gum turpentine and refined mineral oil.
Unfortunately, there is no accompanying explanation of why this should work. I'm dubious about applying oil to a figure that is going to accept paint. Exactly how porous is lead?
Next most common is the application of an acid solution such as vinegar; many have queried applying an acid to a problem caused by acids and some have tried an alkaline. This is either with or without removing any material first. Unfortunately, lead carbonate is also known as white lead and is highly toxic......
My impression, is that much of this advice, while well meaning, is based more on hope and hearsay rather than science. I read one piece (dressed up as being influenced by conservation) which suggested "household ammonia"; my research indicates that lead carbonate is not soluble in ammonia, so aside from neuralising the acids is not likely to do much to the surface white lead.....
Limited by the materials at hand, I have tried some experiments of my own. It is possible to scrape off the white deposits, but being highly toxic I have limited this to a careful limited test. It also does not work on areas such as the base. I have ordered some brushes to experiment further while wearing mask and gloves.......apparently white lead is sweet and was added to bitter wine to sweeten it until banned!
So far, the chemical experiments have been limited to a scrub with an old toothbrush in a highly concentrated detergent solution (only moderately successful) followed by an overnight soak in Detol; knowing it's effect on paint, I did look up it's chemical make up to discover it's a base and /or mildly alkeline - it's also highly toxic to cats and cane toads - who knew! A scrub in the Detol, has done little more than the detergent, but no further harm (and they are much cleaner).
I may try oven cleaner, as this is acidic, on the most effected. However, it seems physical removal, followed by some kind of alkali neutralisation (as simple as detergent) is probably the way to go before I start immersing them in gum turpentine and mineral oil!
Out of interest, the make up of the metal itself is one of the causes; the original Pax Britannica were reputedly made of pewter which partly explained the high cost; the moulds were acquired by Vandrad in the UK and /or RSM (Rusty Scabbard Miniatures) in the US who still produce them AFAIK. Vandrad are long gone and I cannot recall if they imported or produced under licence or owned the moulds. While Steve Hezzelwood (of Pax Britannica) was something of a "rogue", I suspect the castings are later as Pax Britannica were very hard and inflexible, suggesting pewter with very little lead content, unlike these figures so suggesting either RSM or Vandrad with a high lead content - although I thought the US had banned lead in miniatures?