Reply To: Coppering the wooden walls
This may answer the query on thickness of copper sheathing. Taking figures from my copy of Fowler’s Mechanics’ and Machinists’ Pocket Book, [edited William H Fowler, published annually, Manchester, 1908 to 1970], (1961 edition), 28oz/sq ft copper is somewhere between 19 and 20 SWG (Standard Wire Gauge) and is approx. 1mm thick (1mm = 0.03937inch).
32oz is somewhere between 18 and 19 SWG and is approx 1.1mm. thick, the thickness of the blade of my paper knife certified as being genuine copper from the Victory. The mind reels in the face of such proof!
There must be an earlier set of tables to which 40 Gauge refers, but I haven’t found that yet.