This section is from the book "An Elementary Outline Of Mechanical Processes", by G. W. Danforth. Also available from Amazon: An elementary outline of mechanical processes.
Fig. 252 shows the hammers made especially for coppersmiths' use. Their designations and uses are as follows:
(1) Raising hammer. Used to cup flat work.
(2) Planishing hammer. This has polished faces and is used to smooth the marks and wrinkles formed on pipes and other work during the operation of making them by hand.
(3) Collar hammer. Used to chamfer the edge of a sheet for making a lap joint, or for hell mouthing the end of a pipe.
(4) Spanking hammer. Used to smooth the surface of a straight pipe as it rests over a mandrel.