1. Produce components from moulds
two gauge casting

2. Producing plaster components
Introduction
Aims:
To introduce fibrous work
Objectives:
To recognise and understand the processes used in two gauge casting

3. Producing plaster components
Two gauge casting
Can you answer the following?
What are firstings?
What types of reinforcement are used in two gauge casting?
How is the plaster applied to the mould?
List the processes involved in two gauge casting
What is size used for?

4. Producing plaster components
Introduction
Two gauge casting
Two gauge casting is used to produce all manner of fibrous plaster items. The main qualities expected from two gauge casting is to produce a strong lightweight product.
Two gauge casting can be a long and complicated operation so preparation is everything.
Unlike one gauge, care must be taken to prepare the reinforcement before any mixing takes place, so all laths and canvas must be cut to size before the casting process starts.

5. Producing plaster components
Introduction
Two gauge casting
Prepare reinforcement materials (hessian face and backing cut to size lathes that have been soaked
Prepare two amounts of water (firstings and seconds)
Add required amount of retarder to the seconds (you need to know how strong it is to give you time to complete the cast)
Mix the secondings first and the firstings second
Using a splash brush on the firstings and then splash on the mould
Clean off the strike offs

6. Producing plaster components
Introduction
Two gauge casting (cont.)
Apply the seconds to the mould
Put the canvas in place and brush in with the seconds
Position the ropes and lath reinforcement
Apply the rest of the mix to give some thickness to the back of the cast
Place reinforcing wads on the back of the cast
Strike off the mould to complete

7. Producing plaster components
Two gauge casting
You should now be able to answer the following:
What are firstings?
What types of reinforcement are used in two gauge casting?
How is the plaster applied to the mould?
List the processes involved in two gauge casting
What is size used for?

8. THANK YOU