Practice question · Put in order
Arrange the steps of mixing and pouring plaster in order.
- Mix gently, avoiding folding in air
- Sift the plaster into the water
- Let the mix slake for a couple of minutes
- Pour before the mix begins to thicken
- Weigh the water and the plaster to the stated ratio
Hints
- Plaster goes into water, not the reverse.
- Slaking happens before mixing, not after.
Show the answer
- Weigh the water and the plaster to the stated ratio
- Sift the plaster into the water
- Let the mix slake for a couple of minutes
- Mix gently, avoiding folding in air
- Pour before the mix begins to thicken
Why
Slaking before mixing is the step people skip and the one that most affects the result: it lets the plaster absorb water evenly before agitation starts, which produces a denser, stronger set with fewer air pockets in the mould face.
Practise Moulds II: Materials and Procedure
The app has 5 more questions on this lesson, and keeps your place in the course. Sculpture I is free to start.
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