The chemicals in these plating kits should last for years with the limited use they are intended for.
When it's spent, just keep it stored until there's a chemical cleanup in your area.
I still want a nickel kit, for nuts & bolts etc.....
BTW we have an Otto bin at work full of caustic soda, used with a S/S anode & a big battery charger it's pretty good at converting rusty parts into good ones.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.
