this purpose. Vertical runs of cast-iron pipe can be attached to the building structure with vertical pipe brackets or pipe straps. Riser clamps should support the weight of cast-iron pipe at each floor level. When the lead takes on a dull gray appear- ance, the joint is properly caulked. It is ready for finishing. Using a wide iron, lightly tap the lead to make the surface smooth. Horizontal joints are made in the same way, except that a joint runner must be used to prevent the lead from flowing out of the hub before it can harden. This is a rope-like tool made of fireproof material, Figure 19-50. Inspection of the rough-in plumbing must be completed before pipe is covered or otherwise concealed. Supporting Cast-Iron Pipe Cast-iron pipe, because of its weight, must be well supported while joints are being made. Permanent supports must be installed before the first rough is completed. These supports should be placed at every joint on horizontal runs unless the distance between joints is less than 4′. In such cases, a support at every other joint is enough. Use special hangers for Yarning iron Oakum yarn Goodheart-Willcox Publisher Figure 19-48. Use a yarning iron to pack oakum into the bell, forming a seal so molten lead is contained in the bell. Oakum: Loosely woven hemp rope that has been treated with pitch or other waterproofing agent. Used to caulk joints in bell and spigot pipe and fittings. Joint runner: A rope-like tool made of fireproof material used to prevent the lead from flowing out of the hub before it can harden. Caulking iron is used to compact lead into joint Outside caulking iron Inside caulking iron Goodheart-Willcox Publisher Figure 19-49. Tools with offset handles are used to caulk lead. Molten lead Ladle Spring clamp Joint runner Goodheart-Willcox Publisher Figure 19-50. A joint runner creates a dam around the opening of the bell when pouring lead into horizontal runs of cast-iron soil pipe. Chapter 19 DWV Pipe and Fitting Installation 321 Copyright Goodheart-Willcox Co., Inc.