(LEFT) A selection of flasks for different sizes of wax pattern.

(LEFT BELOW ) An amount of water is carefully measured out and a precise proportion on investment powder is carefully added and thoroughly mixed.

(RIGHT) The investment mix is placed in a vacuum chamber and a vacuum applied. This has the effect of  removing excess air from the investment, air which could otherwise lead to air bubbles forming over the wax pattern, later leading to casting faults.

Degassed investment is carefully poured into a flask, taking care not to trap any air in the mix. In some cases the founder will reapply a vacuum after the mix is poured. In this example the wax pattern is to be set into the investment soon after pouring, however often the investment is directly poured over the wax assembly which is fixed to a ‘button’ at the base of the flask.

In this instance, the founder carefully paints on a coating of investment over the pattern, concentrating on filling any areas of detail whilst avoiding the creation of air bubbles.

The founder carefully inserts the painted up wax pattern and assembly, again carefully avoiding creating air bubbles. The pattern is secured in position in the flask as the investment sets and consolidates around the design. After a period of air drying the flask can be placed in a kiln for firing. (See KILN & CASTING).

HOME | SEARCH | CONTRIBUTE

© ARTENERO PUBLISHING 2011