HERA Heraenium Sun Mode D'emploi page 11

bar, Oxygen approx. 1.9 bar. These settings will produce the neutral
fl ame required for melting Heraenium Sun. Place the Heraenium Sun
ingots in the preheated crucible. Hold the torch approximately 40 mm
above the top edge of the crucible. Move the torch around the ingots
in circles to heat them uniformly until they melt and fuse. Once the
ingots have fused, start the centrifugal casting machine immediately.
After casting, bench cool the casting ring. Devest the castings very
carefully. Remove the investment material with care. Sandblast with
aluminium oxide abrasive (110 – 125μm).
4. Trimming and preparing for ceramic facings: After casting, the
copings are trimmed with cross cut tungsten carbide cutters in one
direction only, but without exerting high pressure. Do not use diamond
burs. Do not use rubber polishers on the surfaces to receive ceramic.
Avoid sharp line angles and undercuts. Sandblast and evaporate the
surfaces with aluminium oxide abrasive (110 – 125 μm, 4 bar).
Metal dust is hazardous to health.
When trimming and sandblasting, use a suitable extraction system
and/or facemask (type FFP3-EN 149-2001).
5. Oxide fi ring: 950°C (1742°F) for 10 minutes. The oxide layer must
be stained uniformly. Carefully remove the oxide layer on the facing
surfaces with aluminium oxide abrasive (110 – 125 μm, 4 bar) using a
non-recycling sandblaster, and then clean (e.g. evaporation). When
using either HeraCeramSun ,HeraCeram NP Primer or HeraCeramSun
PreOpaque no oxid fi ring is necessary.
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