Home instruction for sheet metal workers . proper curve shown by the solid lines A B. To avoid this stretch-ing the sink strip should be cut as follows: Let D represent apiece of metal, on which the required number of strips havebeen scribed to avoid waste, as indicated by E and H. The innercurve is first cut away, as shown by the shaded part, F, andthen, before cutting the outer curve a b, the inner curve is flat-tened, and by having the largeamount of metal behind the innercurve no stretching can take outer curve a b is then cutand flattened, when the trueshape is the result. Cut a
Home instruction for sheet metal workers . proper curve shown by the solid lines A B. To avoid this stretch-ing the sink strip should be cut as follows: Let D represent apiece of metal, on which the required number of strips havebeen scribed to avoid waste, as indicated by E and H. The innercurve is first cut away, as shown by the shaded part, F, andthen, before cutting the outer curve a b, the inner curve is flat-tened, and by having the largeamount of metal behind the innercurve no stretching can take outer curve a b is then cutand flattened, when the trueshape is the result. Cut alongc d, flatten the same, then cutthe outer curve c f, and so on,being careful always to start tocut and flatten on the inner transferring the bracket sides, Fig. 142, on to the sheetmetal, the outside pattern is pricked, as well as the outline ofthe molding shown by the dotted line from H to D. The center•dots should be used, employing the dividers for drawing thevarious curves. As two outsides and two insides are required. Fig. 147. The Way to Cut SinkStrip to Avoid Stretching. Making an Ornamental Cornice 115 in this case, cut the outside pattern, and, using this as the pattern,cut two more. Cut along the molded outline shown from H toD, allowing laps as shown, and, using this as the pattern, cutone more. This method saves the trouble of pricking off twoseparate patterns. The cutting of the scroll shown by the shaded part can bedone by using a hollow punch and shears or a small chisel on ablock of lead. In the former case the proper size hollow punchesare used for a and b, then the balance cut out with the handshears. When the scroll is small it is hard to turn the shearsand the chisel is used, Fig. 148, in which A represents a block oflead, B the chisel and C the hammer. When cutting the scrollthe chisel is tilted at an angle, using only the corner, a, givingslight quick blows with the hammer and moving the chisel along
Size: 1907px × 1310px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1920, bookpublishernewyo, bookyear1922
