260 



SHEET-METALWORK 



6) Lay out handle, as in Problem 5; form and solder in 

 piece of tin h cut to fit. Solder on handle over seam of body. 

 229. Three-Piece Elbow (Fig. 300). 

 1) Lay out pattern for each part of elbow, first making f ull- 



FlG. 300. Three-piece elbow. 



FlG. 301. Roof cap and 

 ventilator. 



sized bench drawing. Use methods given in cases of con- 

 ductor elbow (Sec. 226) and roof ridge flange (Sec. 227). 

 Allow laps for lock lap joint on each section of elbow. Allow 

 3/32" lap on each end of central section of pipe to fit over, 

 and solder onto, end sections. 



2) Solder lock joint on each section and solder sections to- 

 gether. 



230. Roof Cap and Ventilator (Fig. 301) . 



1) Lay out and construct 8" cylinder, as in case of roof 

 ridge flange (Sec. 227). 



2) Lay out and construct conical cap for ventilator, as for 



