GC EUROPE Fujivest Super - Manual (Page 11)

11
Focus Edition from GC
1.5 Powder / Liquid ratio
All of the phosphate bonded investment materials
manufactured by GC Europe for the Crown and
Bridgework technique share a common Powder/
Liquid ratio of 100 g to 22 ml (with the exception
of GC Vest-G, please consult the ‘Instructions for
Use’).
In order to obtain consistently accurate castings
the correct powder/liquid ratio must be used, as
this ratio is the result of comprehensive laboratory
development and batch testing.
Any alteration of the ratio is likely to result in less
predictable expansion properties, inferior casting
surface and an increased risk of mould fracture.
The use of an accurate electronic balance for
weighing the powder together with a measuring
cylinder or pipette for the liquid is highly
recommended. It is also suggested that only
distilled water is used when diluting the
investment liquid.
Ringsize Powder Liquid
X1 60 g 13,2 ml
X3 150 g 33,0 ml
X6 300 g 66,0 ml
X9 420 g 92,4 ml
1.5.1 Atomized measuring equipment for
investments
Whilst as previously discussed in sections 1.3 &
1.5 the use of accurate measuring equipment and
a temperature controlled refrigerator should
guarantee consistent results, an alternative method
exists in the form of atomized measuring
equipment. This combines an integrated cooling
system with precise measuring technology to
produce a consistently accurate temperature
controlled ratio of water, investment liquid
and investment powder to produce highly
accurate mixing results and subsequent castings.
These devices need to be programmed with
correct ratio and it should be noted that as the
measuring of the liquids is done by weight for
increased accuracy the precise input of the liquid
density is a critical factor. The correct densities
for GC Europe phosphate bonded investment
liquids are listed in the table below.
Liquid Density
(g/cm 3 )
GC Fujivest II Liquid 1,25
GC Fujivest II Low Expansion Liquid 1,15
GC Fujivest Super Liquid 1,14
GC Fujivest Super High Expansion Liquid 1,23
GC Fujivest Platinum 1,14
GC Vest-G 1,19
GC Stellavest 1,23
GC Fujivest Premium 1,25