CHAPTER XVII. ANOTHER WAY OF STRIKING MEDALS WITH THE SCREW.

You make an iron frame of similar size & thickness to the one described above, but of sufficient length to enable it to hold not only the two dies,taselli, on which the medal is cut, but also the female[108]screw of bronze. This screw is set beneath the male screw of iron;[109]one ought really to apply the term screw,vite, to this male screw only, the female screw being calledchiocciola. The male screw should be three fingers thick and its threads[110]square, because it is stronger thus than of the usual shape. The frame has to have a hole in the top of it to admit of the screw passing through it. When you have placed your dies,taselli, beneath the screw, with the metal you propose to strike between them, you tighten them up by the insertion of iron wedges[111]so that they cannot possibly shift. You will find this necessary owing to the greater size of the bronze screw.[112]Then having prepared a piece of beam about two cubits long, or more, you fix an iron rod of sufficient thickness and of about two cubits in length to the lower end of it, and it must fit into the beam;[113]then fix your frame into a cutting in the head of the beam made exactly to hold it. It is necessary, too, to bind the beam round with stout iron bands to give it strength at the place where the frame is set in, and to prevent it from splitting.

Round the head of the screw must then be fitted a stout iron ring with two loops to it, & these have to be made to hold a long iron rod or bar,[114]say six cubits in length, so that four men can work at it, and bring their force to play upon your dies and the medal you are striking. In this method I struck about one hundred of the medals I made for Pope Clement; they were done in the purest bronze without any casting, which, as I told above, is necessary for the process calledconiare. I advise every artist tonote well this method of striking with the screw, for, though it be more expensive, the impressions are better, and the dies not so soon worn out. Of the gold and silver medals I struck many straight off withoutsoftening? them first; & as for the cost, perhaps after all it only appears greater, for whereas in the method of striking with the screw[115]two turns of the screw will complete the medal, in the method of striking in theconiareprocess at least one hundred blows with the stamps are necessary before you get the desired result.

Diagram illustrating the process of striking medals with the screwD. DIEM. MEDALAT ‘A’ WOULD COME THE FEMALE SCREW, AND THE WEDGES WOULD COME AT THE SIDES OF THE DIES.

FOOTNOTES:[108]La vite femmina.[109]Il mastio di ferro: i.e.,so that the male screw can fit into it.[110]Pani.[111]Biette.[112]Gli e di necessita che per la grandezza della chiocciola di bronzo, la quale ha da essere fatte in modo che la non balli nella staffa.[113]A quella si attacca nella testa di sotto un pezza di corrente ... e bisogna che sia commesso in nella testa di sotto nella detta trave.[114]Cioè a un lungo corrente.I give on the next page a diagram of what the upper portion of this machinery was probably like. Or it may be as Prof. Roberts-Austen shows it in the drawing in his Cantor Lecture on Alloys, Society of Arts Journal, March-April, 1884.[115]Colpi di conio.

[108]La vite femmina.

[109]Il mastio di ferro: i.e.,so that the male screw can fit into it.

[110]Pani.

[111]Biette.

[112]Gli e di necessita che per la grandezza della chiocciola di bronzo, la quale ha da essere fatte in modo che la non balli nella staffa.

[113]A quella si attacca nella testa di sotto un pezza di corrente ... e bisogna che sia commesso in nella testa di sotto nella detta trave.

[114]Cioè a un lungo corrente.I give on the next page a diagram of what the upper portion of this machinery was probably like. Or it may be as Prof. Roberts-Austen shows it in the drawing in his Cantor Lecture on Alloys, Society of Arts Journal, March-April, 1884.

[115]Colpi di conio.

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