二、Determine the weight of powder and the volume of water
Diameter of Flask(mm)
Water/Powder ratios
Height of Flask(mm)
85mm
100mm
150mm
200mm
250mm
75(mm)
Powder(g)
540
640
950
1300
-
Water(cc)
205-215
243-256
360-380
494-520
-
85(mm)
Powder(g)
700
820
1230
1630
2000
Water(cc)
266-280
311-328
467-490
620-650
760-800
100(mm)
Powder(g)
960
1120
1680
2250
2800
Water(cc)
365-384
426-448
638-672
855-900
1060-1120
125(mm)
Powder(g)
-
1750
2600
3500
4300
Water(cc)
-
665-700
990-1040
1330-1400
1630-1700
Note : The formula delermining the weight of power according to size of flask is : W(g)=0.0045×R2×H Among them : W=Weight of power (g) R=Radius of flask (mm) H=Height of flask(mm)
三、Instructions：
■ Weigh investment
according to size of flask.
■ Measure water.
investment: water=100: 38-40)
■ Always add investment to
water.
■ Mix manually for 30 seconds,
then by electric mixer 2 minutes.
■ Vacuum up 1-1.5 minutes
(no more than 2 minutes)
for remove air from slurry
■ Pour into flask, until
investment level above sprue
tree 1.5-2cm
■ Vacuum up air from flask to
1.5-2 minutes.
■ Leave still for least 2 hours.
■ Preheat oven about 150℃.
■ Scrape away excess investment
from top of flask, remove sprue
base.
■ Load flask into oven.
■ Follow procedure showing
in Fig.1 to get into lost-wax
burnout cycle.
