Pattern Allowances: Shrinkage/Contraction, Machining/Finish, Draft / Taper, Distortion / Camper, Shake / Rapping

Pattern Allowances Pattern is always larger in size than that of final casting. Because, certain allowances are provided due to metallurgical (shrinkage) and mechanical (machining draft, shake and distortion) reasons. The various allowances in pattern are (i) Shrinkage/Contraction (ii) Machining/Finish (iii) Draft / Taper (iv) Distortion / Camper (v) Shake / Rapping Shrinkage Allowance Practically all metals … Read more

PATTERN ALLOWANCES: Shrinkage Allowance, Machining Allowance, Draft or Taper Allowance, Rapping or Shake Allowance, Distortion Allowance, Mold wall Movement Allowance

 PATTERN ALLOWANCES Pattern may be made from wood or metal and its color may not be same as that of the casting. The material of the pattern is not necessarily same as that of the casting. Pattern carries an additional allowance to compensate for metal shrinkage. It carries additional allowance for machining. It carries the … Read more