Casting process selection — small decorative hollow items Which casting method is most suitable for producing hollow, thin-walled ornaments and toys from non-ferrous alloys?

Introduction / Context:
Lightweight decorative parts, ornaments, and toys often need thin walls and good surface finish without heavy cores. Selecting an economical process for small runs is important for cost and quality.

Given Data / Assumptions:

• Non-ferrous alloys such as zinc, pewter, or low-melting aluminum alloys.
• Hollow, thin-walled geometry desired.
• Relatively small parts; short to medium production runs.

Concept / Approach:
Slush casting pours metal into a (usually metal) mould, allows a thin shell to solidify against the mould wall, and then pours out the unsolidified core. The result is a hollow casting with thin walls and good surface finish, ideal for ornamental work.

Step-by-Step Solution:
Fill the mould with molten metal and wait for a controlled skin to solidify.Invert and drain the remaining liquid metal.Eject a hollow, thin-walled casting suitable for finishing.

Verification / Alternative check:
Product catalogs for decorative items frequently mention slush casting; wall thickness is controlled by dwell time before draining.

Why Other Options Are Wrong:
Permanent mould (static) yields solid or cored parts, not thin shells; die casting fills the cavity fully under pressure, producing solid walls; centrifugal casting targets symmetrical tubular shapes; shell moulding is a sand process suited for detailed solid castings, not hollow shells without cores.

Common Pitfalls:
Poor timing causing walls too thin or too thick; inadequate venting leading to surface defects.

Final Answer:
Slush casting