GC EUROPE Pattern Resin LS - Manual (Page 10)

10
Investing
and
casting
Questions
and
answers
Mixing ratios:
When investing Pattern Resin LS workpieces, always use
a higher proportion of investment liquid than with wax
patterns. For details please refer to the instructions for
use of the respective phosphatebonded investments.
Modelations:
All Pattern Resin LS workpieces should be covered with a
thin layer of wax to avoid deterioration of the investment
surface during heating-up.
Heating-up:
In connection with larger Pattern Resin LS workpieces,
heat up progressively to avoid aggressive burningout. It
is recommended that the temperature is kept at 250° C
for 1 hour before raising to the final burn out.
1. Should I insulate the surface of the primary
component before building up Pattern Resin LS?
Insulation of the primary component is not required if
Pattern Resin LS is used on a smooth, milled metal
surface.
2. How can I tell that I am using the right mixing ratio
of powder and liquid for the brush technique?
After dipping the wet brush into the powder, the little
bead on the tip of the brush should be slightly wet and
have a shiny surface.
3. Which burs are recommended for adjustments of the
polymerized Pattern Resin LS surface?
For adjustments or milling use tungsten carbide burs or
cross-cut instruments.
4. Can I mill the surface of Pattern Resin LS in the same
manner as wax?
Dies and workpieces made of Pattern Resin LS can be
shaped, contoured and milled by means of a milling
machine.
5. Which steps should I observe when I use Pattern
Resin LS on stone dies?
Check the stone die, stumps or cavities for undercuts,
inaccuracies or rough surfaces. Block-out undercuts with
an appropriate wax and seal the die surface with Die
Hardener. Wet the cavity or stump surfaces with a
separating agent.
6. In connection with the brush technique, can I apply
Pattern Resin LS in small dots?
Pattern Resin LS can be built up in small sections or dots.
Each section will polymerize separately and adhere to
the other sections. After covering the complete base,
Pattern Resin LS shows a homogenous surface. This
technique minimizes total polymerization shrinkage.
7. How can I clean the brush?
For intermediate cleaning dip the brush into Pattern
Resin LS liquid and dry with a tissue.
8. How can I remove a secondary pattern from the
primary omponent in a safe and easy way?
Small opposing retention beads attached to the surface
help to remove the pattern.
9. Should I treat Pattern Resin LS objects with a wetting
agent before investing?
Generally, the quality of casting surfaces depends on the
use of a wetting agent. However, if Pattern Resin LS is
applied on smooth or polished metal surfaces without
undercuts, there is no need to use a wetting agent. If
there are wetting agent residues the internal surface of
the cast restoration will not be smooth.