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.
Beaded Joint occurs when squares are stopped with fixed or shifting beads attached to the sash with nails or screws. Occasionally they are brass bronzed and moulded, and fixed with brass screws through countersunk holes. In all cases the edges of the glass should be run with black paint previous to stopping.
This will be found under various heads. In ordinary work a square of glass is bedded upon the back putty, which is the term applied to the putty first laid in on the rebate. The front putty completes the stopping, and is run along the edge of the rebate on the other side of the glass.
This is formed between two pieces of glass which fill a square, but do not lap, and is sometimes adopted in shop windows to save the expense of a large pane.
Lights are fixed in grooves in stone by means of oil cement, consisting of Bath-stone dust and boiled linseed oil, the grooves being first sized. Common putty softened with olive oil is sometimes preferred. Portland cement will cause the glass to crack. The cement used for lead lights is a mixture of whiting and white lead, which is dusted over the lead grooves after they have been run over with a thin paint. In the case of iron sash bars a mixture of 1 part tallow and 2 parts resin is laid on after the bars are made hot. Whatever cement, however, is used, whether common putty or any other improved variety, it must not be of a kind to get brittle, owing to the expansion and contraction of the iron sash not being the same as that of glass; and it is also essential that there be no contact between the iron and the glass.
India-rubber Joint is made by glueing to the rebate a strip of vulcanised india-rubber, and another one to the inside of the bead or moulding, which is screwed on to the frame to secure the square.
This is common in greenhouses, and is seen sometimes in shop windows where there are no cross bars and the panes are made up of two pieces. It is essential in roofing. Glass tiles and panes of glass in skylights and sloping surfaces always have lap joints at horizontal junctions, bars being inadmissible except in patent systems of glazing without putty, and when the pane is large its tail is connected with the head of that below with a zinc or copper tingle, having oppositely bent ends like those of lead used in replacing slates. When the lap is vertical not much overlap is necessary, but when sloping an inch or more is indispensable to prevent leakage through capillarity or driving winds, and a pointed or rounded tail is preferable to a square one, as it concentrates and expedites the flow of water off the joint.
This occurs when small pieces of glass are joined together by means of grooves in leaden slips or strips called cames, having an H section so as to form panels or lead lights. Usually a panel consists of a collection of small diamond-shaped panes, held in place by two parallel rows of cames, which cross one another diagonally, and are soldered at their intersections, the whole being surrounded on the outside edge by what is called a broad lead, that is a broader strip than the others, or about f in. in the leaf. The panes are inserted by bending down the sides of the cames and then turning them back again to grip the glass; and in order to keep out the weather the lights should be cemented, as described under Cement Joint.