Butt Joint

Butt Joint is made between two pipes by means of a steel core or cast iron cylinder fitting the bore of the pipes when raised to the same heat as the solder, and attached to a chain for regulating its position and extracting it. The ends of the pipes are cut and shaved truly to a close butt and butted together over the cylinder, the joint being wiped in the usual way and finished off with the common bulbous protuberance.

Caulked Joint

This occurs when molten lead is used to form a joint between stone and ironwork, or as noticed under Burnt-in Joint and Bun Joint. As the metal contracts in cooling, it has to be "set up" or caulked, that is, punched into its seat when cold.

Cement Joint

A mixture of tallow and resin is denominated plumbers' cement, being useful amongst other purposes for securing the bottom valve of a pump. The two ingredients are carefully melted and mixed over the fire in such proportions as to make the mixture sticky and stringy, and not greasy or brittle. Sometimes brick dust is added. In this trade cement is a general term for any kind of stopping used for joints. It includes putty, white or red lead, or the two combined (described under Flange Joint), etc.,all of which, however, being liable to be cracked by shaking or settlement, or to become loosened by drying up, can never be wholly depended upon for the total exclusion of sewer gas unless used between flanges or screw threads.

Cistern Joint

Cistern Joint is a wiped soldered joint, the water preventing tension.

Cone Joint

This is a plan adopted by Messrs. T.

Lambert & Sons to connect lead pipe to wrought iron tubing without solder, and is shown in Fig. 138. A gland nut having been passed over the lead pipe, it is opened out by means of a turnpin having the same taper as the purposely tapered end of the iron main or wrought iron tubing, so that the two ends only have to be drawn together by bolts and nuts to make a perfectly sound joint, whilst the fullway is preserved.

Copper-bit Joint

Copper-bit Joint is a soldered joint made with a copper-bit and fine solder in strips, sticks, or cakes, the latter of which are about 4 in. by 6 in., and from in. to f in. thick. Sometimes, however, the position of a joint is such that it is more convenient to use the bit than the bulbous grosing iron after the molten solder has been poured over it, but this of course is not a genuine copper-bit joint. The copper bit, called also a soldering tool or soldering iron, two varieties of which are shown in Figs. 139 and 140, consists of a bit or bolt made of copper, having a hatchet-shaped or else a pointed nose or end. It is held by a wooden handle secured to a short iron shank riveted to the bit. The hatchet-shaped variety is generally used by plumbers, who often call it from its shape the hatchet bolt, whilst gasfitters find the pointed kind most convenient. Before using the bit it has to be tinned, that is, a face of solder is given to it, which is effected in various ways, an old fashioned one consisting in heating it to a dull red, then cleaning it by quickly filing bright its nose or extremity, rubbing it instanter upon a piece of sal-ammoniac (muriate of ammonia), and immediately afterwards on a "tin pan," which is a piece of tin or copper

Copper bit Joint 139

Fig. 138.

Copper bit Joint 140

Fig. 139.

Copper bit Joint 141

Fig. 140.

plate on which a few drops of solder have been deposited. Finally, if necessary, it is wiped with a piece of dry tow or cloth. It can then be re-heated and used at a great heat, but not made red-hot, else the face will be burnt off. The more modern plan is to use plenty of spirit of salt (hydrochloric acid) killed, that is, turned into chloride of zinc by putting scraps of zinc into it. When ebullition ceases it is diluted with a little water, and after cleaning as above, the hot end of the tool is momentarily plunged into it and then touched with solder, and similarly touched and plunged again and again until the face is nicely tinned. The bit must always be tinned with the same flux as is used for the soldering, so that if resin is used the extremity of the bit prepared as already explained has merely to be well and expeditiously rubbed upon a mixture of a little powdered black resin and a few drops of solder. In soldering together the edges of zinc, a face having been put on the bit with killed spirit, this fluid is applied to the work with a small brush or piece of stick or cane, and then the strip of solder is drawn along the joint with the left hand whilst the copper-bit follows it in the right. Care must be taken to wipe off all stains of the salt with a wet cloth. Pieces of lead are somewhat similarly united with resin as a flux. Brass and wrought and cast iron piping and fittings are brushed with the above liquid, or a solution of sal ammoniac, or unkilled hydrochloric acid, which is the best for iron (the iron surfaces being first filed clean and bright), and then thoroughly well tinned with a little of the solder and tinned copper-bit, otherwise the solder will not hold properly. The joint is then made by expeditiously floating more solder and well sweating it about the parts. Cast iron requires a very hot bit to make a good joint, but of course not hot enough to take its face off, and the iron must be scraped or by some means or other got quite bright before tinning, which if perfectly well done as just described will give the solder an inseparable bold.