Green’s Dictionary of Slang

1. (Aus.) a cook on an outback station, usu. derog.

1933		(ref. to 1890–1910) L.G.D. Acland Early Canterbury Runs (1951) 362: Blacksmith – A term of contempt for a bad cook.
1945		Baker Aus. Lang. 79: Outback cooks have been known by many names [...] bab, babbler, babbler’s offsider, babblins, baitlayer, doctor, blacksmith, poisoner and crippen.
2003		McGill Reed Dict. of N.Z. Sl. 24: blacksmith A poor station cook who burns the food.

2. (UK Und.) a forger.

1906

O.C. Malvery Soul Market 290: A forger is a ‘blacksmith’.

3. (US Und.) a safebreaker.

1926		J. Black You Can’t Win (2000) 258: A more careful and experienced ‘blacksmith’ would have taken measures to prevent that big safe from falling on its face.
1949		Monteleone Criminal Sl. (rev. edn).