PATTEKN MAKING 75 



leave all patterns for brass or bronze, in the natural color of the 

 wood, and shellac the core prints red. If the pattern is intended for 

 moulding cast iron, the body of the pattern is made black and the 

 core prints red. The parts of the core box in which the core is 

 to be formed are also colored red and the outside of the core 

 box black. The black color is produced by mixing lamp black 

 with the shellac varnish, and the red color by mixing vermil- 

 lion (Chinese is the best) with the shellac. The vermillion is 

 heavy and will settle, hence it must be stirred or well shaken 

 before using. The best method is to first use two coats of the 

 natural colored shellac (orange or white) on all surfaces of the pat- 

 tern, core prints and core box, then apply the black or red for the 

 last coat only. 



Aa the pattern already described is for a brass bushing, the 

 body should be left the natural color of the pine, and the core 

 prints on the pattern and the inside of the core box colored red. 



The outside of the core box may be left the natural color or 

 made black, as preferred. The outside of the core box, having no 

 part in the formation of the core, is not necessarily so well and 

 smoothly finished as the inside. 



All nail holes or any defects in the wood should be filled with 

 beeswax applied with the warm blade of a knife, or narrow chisel, 

 warmed by holding in hot water. The beeswax should always be 

 used after the first coat of shellac has been applied, as it will then 

 hold better. The sand-papering of the pattern, after the first coat, 

 will smooth the wax and bring it even with the surface of the wood 

 The time required for a coat of shellac to dry is from eight to 

 tw r elve hours, depending upon how heavily it may have been ap- 

 plied, even though to the touch the surface may seem ary in one 

 or two hours. 



If a hard, durable surface is required on the pattern, twelve, 

 or better, twenty-four hours must be given between each coat. The 

 roughness will then sand-paper off as a dry powder without gum- 

 ming the sand-paper, and leave a hard, smooth surface for the suc- 

 ceeding coat of shellac. 



The second casting to which attention is called, is the brass 

 leai'infj represented in Fig. 149, which is to be finished all over. 

 On examining the drawing, first with regard to removing the pat- 



