DeguDent Optivest Instrucciones Para El Uso página 9

5 Preparation of the casting mould (lining)
5.1 Reduction of tension
Apply or spray a thin layer of Waxit wetting agent to the wax object and then blow it dry carefully (do
not use compressed air !).
5.2 Fine investing
Due to the fine grain size of the Optivest powder and the compatibility with all modelling materials,
fine investing is not required.
5.3 Mixing the investment compound
Dose and mix Optivest powder and mixing liquid as described in 4.1. We recommend to select a
concentration of the mixing liquid of 60 %. The mixing ratio of water : liquid should be 100 g : 15 ml.
5.4 Investing
Let the mixed investment compound flow into the casting mould under light vibration; the formation
of bubbles must be avoided. After the casting mould has been filled, switch off the vibrator immedia-
tely.
5.5 Setting
Let the casting mould set for approx. 60 min. After the investment compound has set, the upper
surface at the casting ring should be trimmed slightly in order to remove the glaze layer to ease the
escape of gases.
5.6 Wax elimination
Place the casting mould into a furnace which has been preheated to 300 °C and eliminate the wax
for approx. 45–60 min. Place the casting ring into the furnace with the casting funnel facing down-
ward.
5.7 Preheating
After the wax has been eliminated, bring the casting mould to the final temperature of 1000–1050 °C
recommended by the manufacturer. The heat rate should not exceed 8 °C/min. The final temperatu-
re should be kept for 60 min; if a larger number of casting rings is used, the time must be extended
correspondingly.
5.8 Casting
Cast according to the processing instructions provided by the manufacturer of the alloy.
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