Practice question · Sort into groups
Sort each mould by how it deals with undercuts.
Groups: By being destroyed · By being divided · By stretching
- Silicone mould
- A rigid mould made in five parts with keys
- Alginate over a hand for life casting
- A plaster mould chipped away from the cast
- Waste mould
- Piece mould
Hints
- There are only three answers to the undercut problem.
- Anything chipped off afterwards is in the first column.
Show the answer
By being destroyed: Waste mould, A plaster mould chipped away from the cast
By being divided: Piece mould, A rigid mould made in five parts with keys
By stretching: Silicone mould, Alginate over a hand for life casting
Why
Three strategies exhaust the possibilities, which is why the typology is short. Everything else — mother moulds, keys, release agents — is machinery serving one of these three decisions.
Practise Moulds I: Typology
The app has 5 more questions on this lesson, and keeps your place in the course. Sculpture I is free to start.
More questions on Moulds I: Typology
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- Addition-cure silicone can be prevented from curing by contact with sulphur-containing plasticine.
- Which are true of alginate as a moulding material?
- Complete the mould vocabulary.
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- A waste mould resolves undercuts by destruction rather than division or stretching. What does this principle…
- Arrange the steps of deciding how to mould a form, in order.
- The division lines of a piece mould can be placed anywhere, since the seams are cleaned off the cast…