This section is from the book "A Practical Treatise On The Joints Made And Used By Builders", by Wyvill J. Christy. Also available from Amazon: Practical treatise on the joints made and used by builders.
An old-fashioned variety of wiped pipe joint, characterized by having the bulbous protuberance ridged or ribbed and somewhat unfinished in appearance when contrasted with the smooth symmetrical and turned-like surface of the ordinary wiped joint. The striped variety is said to be stronger than the other owing to the solder being less disturbed in setting, which is owing to the plumber using less solder, and the wiping cloth less, but the iron more. Others attribute its greater strength to the process consolidating the solder and preventing " weeping," whilst others again maintain that its only advantage is to be found when very coarse solder - 3 or 4 of lead to 1 of tin - is used, which would set quickly and be porous were it not glazed over by striping or overcasting. The ribs, ridges, or furrows are made with the heel of the iron when barely hot enough to melt the solder, but whilst the solder is still hot, by passing it up and down all round the joint from end to end, thus leaving a series of lateral flutes about ½ in. wide at the centre and dwindling away towards the extremities.
This can be made like the common branch soldered joint, or a T may be inserted as explained under Union Joint, but this plan in water-fittings is not considered so suitable as a well-made branch joint.
Taft Joint is used for uniting lead pipes, and is made by tafting or slightly enlarging or opening the end of one pipe and inserting therein to the depth of about ¼ in. or in. the lightly rasped end of the other, which must nicely fit it without any burr being left on the inside, or in any way interfering with the full bore. The lead round about the joint must then be shaved perfectly clean and bright, the ends brought closely together again, a little resin shook around the junction, and the cup filled with fine solder with the blowing lamp. As a general rule the edge of the inner pipe should not face the current. Another kind of taft joint is made when lead pipes are soldered to cesspools or gutters, surrounded on all sides by walls or parapets to conduct the rain to ordinary down-pipes or rain-water pipes. Before laying the lead a hole is cut in the gutter boarding sufficiently large for the pipe, and sufficiently sunk to allow the gutter lead and the tafted edge of the pipe as well as the solder to lie upon each other flush with the general surface, as in Fig. 149. When the plumber lays down the lead he hammers it close upon the hole, puts the piece of pipe through from the top, dresses or beats, that is, tafts the edge of the pipe nicely over the edge of the sheet lead, prepares as usual for wiping, drives in a couple or so of clout nails to keep all in place, and finishes off the tafting with wiped soldering perfectly flush with the level surface of the lead.
A sound and reliable connection impenetrable by rain, etc, in roof coverings, but in piping impervious alike to air or water.