Page:The Building News and Engineering Journal, Volume 22, 1872.djvu/228

 212 THE BUILDING NEWS. - Maren is 1872. Im this article the style of using sheet zinc in place of lead is to be described, and for illustration I shall take a flat 17ft. long by 15ft. broad, with a raised division run- ning up its centre. Fig. 34 is section of such flat, P being square wooden block or frame, 3in. broad and 3in. high, running up the whole length of flat. Instead, how- ever, of supposing this flat to be situated upon the top of a “hipped” roof, with four trapezoidal inclined sides,’ as was flat in former article, I shall suppose it to be bounded at ends by two gables, in which case Fig. 35 shows longitudinal section as distinguished from longitudinal section shown by Fig. 25. The first thing to be done here is to nail on a long narrow strip of sheet lead 17ft. long by 4in. broad all along front of flat on each side just as is shown by Z, Fig. 23, then to cover slates put on the two flashings—whether lead or zine—one on each side, as shown by dotted line, Fig. 23. Then bend down top half of lead strip, which is to form “clinch,”* as per Z, Fig. 24, and then plane its edge straight. Provision must now be made for laying down the zine on top of flat, but it must be understood how wide the sheets are to be. As the general size of zinc sheets is Sft. by 3ft.t, we shall take that as the size to be used here, and as Tin. is to be taken up by portion of each side set up, that leaves breadth of sheet lying on flat to be 2ft. 5in., and as flat is 17ft. long it will take up about seven such breadiths in its length. In order to lay the sheets as regularly as possible, the first one—after one side has been set up 4in., and the other side din. high —amay be placed in centre of flat, as at Q, Fig. 35, then all up each side wooden rolls are to be nailed on, of which Fig. 36 shows full-sized section suitable for 2in. zinc roll caps; this wood roll is 1iin. broad, and about 28in. high over all. This wood roll, which extends from central division block to edge of flat, need not be made all in one piece, for it may be made and fixed on more readily in two pieces by making portion be- low dotted line of a separate piece, and nail- ing it on first, and then nailing the larger piece on above it afterwards. We shall take this latter plan, and nail on a in. by din., piece all up each side of Q, Fig. 35; then, at a distance of 2ft. 5in. + in. from each side of Q, nail on other two of these pieces as at RS, Fig. 35, and at a similar distance nail on other two pieces, as at T U, Fig. 35. All these pieces, or wooden strips, are each 7ft. 44in. long. When they are nailed on, and the seven sheets of zinc laid down in their site with the top ends of all next cen- tral block, or division frame P, Fig. 34, set up Sin. high (which it will be understood is independent of the one side being set up 4in. and the other side 3in. high), the principal portion of wood rolls—yviz., that above dotted line, Fig. 36—is then nailed on; but to nail it properly a gimblet ought to be used to bore through wood-roll first, which causes the nail when driven down to go in where wanted. Either nails or screws may be used about Shin. or 4in. long. The zine is then brought over rolls as per dotted lines, Fig. 37, the 4in. upstand of one side overlapping the sin. upstand of other side asat VV. While putting on these sheets the end of zine next central block, P, Fig. 34, has to be soldered at corners. The side of zine with sin. upstand should be soldered first, then the 4in. one, which overlaps it, and it must be an axiom with the plumber not to solder two different sheets together, but to keep each sheet by itself. in soldering zine diluted muriatie acid, or “spirits of salt” is used. In the Family lead ig used the clinch lies closer, and a better and neater job is, therefore, made, + “Sheet zine is always attainable in sheets sft. and 7ft. long, by 3ft. and 2ft. Sin. wide, but it may be rolled of any length under 12ft. For specially rolled sheets about ® month's notice should be given, and for lengths over 10ft. an additional cost of about £2 per ton is incurred for rolling."—From printed circular of Vieille Montagne Zinc Mining Company. = Herald for March 2, 1872, I find it stated that in preparing spirits of salts for solder- ing it requires to stand several days ina also to be shaken up every twelve hours; but that is simply a mistake, as the mixture does not require to stand even twelve minutes. In practice, the plumber pours a little of the “‘spirits ” into a small dish, say a saucer, a jelly-can, or a lead dish, set up as per Fig. 6, p- 170, about 6in. square, and say 2in. deep, then some small pieces of zine are put in, and in a minute or two the mixture is ready for use. I have just made a trial of a mix- ture called ‘“ Baker’s Preparation for 'Tin- ning and Soldering ;” but I find the specimen I got not to be equal to the spirits, especially when applied to old or tarnished zinc, neither did it clean the soldering-bolt half so well. The acid, as I have said above, is diluted by dissolving a little sheet zinc in it. When the zinc is put in among the acid a violent ebulli- tion sets in, which, however, soon subsides. If alight be put to it during ebullition the gas given off will go on burning for a short time. The soldering here is done by means of copper bolts. Theacidis put on with a small piece of cane or a small brush. The front edge of zinc sheet has then to be clinched, as shown by K, Fig. 28; only before doing so about 1}in. has to be cut off end of sheet, it being in this case that much too long. The portion of upstand projecting beyond K is also cut away, so as to allow zine to be turned in. The zinc being turned in, as per K, is then to be bent down as per L, Fig. 29; but as zine will not work down at the corners in the same manner as lead, the upstands have first to be slit down close by end of wood-roll to allow zine to be bent down. When clinched and bent down as per L, Fig. 29, a small piece of zinc has to be inserted and soldered to each front corner of zine sheet, and so soldered as that each sheet is kept distinct and by itself. The size of this small piece is about 2in. square. The two front corners of each sheet, there- fore, project out before butt end of wood- roll fully 14in., as per Fig. 38, the depth of projection being about 3iin. over all. The zinc-roll caps have then to be slid on as per outer circle at W, Fig. 37, and in order to protect front edges of zinc sheets projecting in front of wood-rolls a short piece of the zine-roll—about 43in.—has to be taken and put on perpendicularly, being first mitred with front end of horizontal zine-roll, and then both soldered together at mitre. The inner edge of this short perpendicular piece of zine-roll is to be kept about Jin. back from front edge of flat, just as bottom of horizontal zinc-roll is raised a little above flat. Fig. 39 (which is drawn on a smaller scale than Fig. 38) shows the roll- cap on, Fig. 38 showing it off. The end of zinc-roll which is next, or comes up against central block P, Fig. 34, has a small piece of zine soldered round it, over which the apron of saddle comes, so as to make all properly watertight. ‘The sides of zine sheets which are next gables are bent up about Sin. high, and an apron put on as per X, X, Fig. 35. A pailful of clean water and a brush should then be got, and the whole of zinc brushed over, so as to clean off all spirits of salt stains, &c.—in fact, the water and a small brush should be there all the time. The one side of flat being covered as above described, the same is done to the other side of flat, and after saddle is put on the work is finished. This ‘ saddle” is put on as per Y, Fig. 40, the dotted line showing section of lead. ‘The saddle Y, here shown, it will be understood, rests upon P, Fig. 34, P being also represented here as supporting Y. The wood for this saddle is 17ft. long (the length of flat), 5in. broad, and about lin. thick. After it has been nailed on, and covered with lead about 1ft. broad, as per dotted line at Y, the plumber work of flat is finished—i. e., unless plumber has also to ‘‘point” the raggles with mastic or cement, which ‘ pointing” in some places is left for the slater to do. Al- though I have mentioned lead as the material to be used for saddle, yet, if preferred, zinc may be used, and put on inridge style. The
 * [ recommend a /ead strip for clinch because when
 * bottle after the zinc has been put into it, and