Metal Patternmaker how-to

How to Add Shrink and Draft to a Pattern

Allowances make castings the right size.

Updated By the Career Education Institute Curriculum Team
Quick answer

Allowances make castings the right size. In short: check; use; add, then complete the remaining steps below.

Step by step

  1. Check the metal.

  2. Use a shrink rule.

  3. Add machining allowance.

  4. Add draft to vertical faces.

  5. Add fillets.

  6. Check the drawing.

Safety reminders for metal patternmakers

  • Follow machine safety
  • Ventilate resins
  • Wear PPE
  • Use dust collection

Pattern · Draft · Shrink allowance · Core box · Match plate · Parting line: see the full metal patternmaker glossary.

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