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Post-Machining Treatments
Heat Treatment
Heat treating of Porcerax II should be done in a vacuum furnace. As supplied,
Porcerax II has a hardness of 35 HRc. It can be heat treated to 50-52 HRc;
however, Porcerax II carries a fairly high potential for movement. Strict
guidelines are supplied by Molder's World, Inc. and should be followed.
Hardness
Porcerax II is 20-30% porosity by volume and will give false or misleading
readings if tested with either a Rockwell or Brinell hardness tester. As the
load of either of these testers is applied, the pores beneath the surface will
collapse and render a false reading. It is recommended that a micro Vickers
hardness tester (50 or 30g load) be used to test the hardness of Porcerax II.
Texturing
Porcerax II can be textured. In order to prevent the possibility of destroying
the internal vent structure of the material, certain procedures must be strictly
adhered to. It is imperative that the chosen texture source know they are
working with Porcerax II. If they don't, the likelihood for permanent,
irreparable damage to the piece is virtually assured. The pores of the material
must be thoroughly cleaned and properly sealed prior to texturing. Failure to do
so results in the etchants used in the texturing process leaching into the pore
structure and rusting the venting closed. This rust is permanent and cannot be
removed once it has occurred. The piece will be useless and must be replaced.
Thousands of molds worldwide have been
successfully textured. However, it is imperative that the molder and/or mold
maker's texture source come supplied with the information needed to properly
process the piece. We strongly advise against inserting Porcerax II into an
already textured surface. The perfect venting of Porcerax II results in much
higher resolution of the grain at the inserted area and a dramatic reduction in
gloss. It is recommended that the entire textured surface be Porcerax II. Please
consult your graining source for more information.
Surface Reproduction
Porcerax II provides perfect venting of all gases from the mold. While this is
desirable in most cases, the venting of the Porcerax produces a perfect
"marriage" between the resin and the molding surface, thus producing a
dull, matte finish. If Porcerax II is used as an insert on the cavity side, the
result will be two dissimilar appearances due to differences in gloss and
texture definition. This may be acceptable if the parts are painted after
molding.
Water Lines
Molder's World, Inc. does not recommend running water through Porcerax II, if
at all possible. However, occasionally the need will arise, due to size or
application considerations, to water-cool Porcerax II. There are a number of
ways to accomplish this. In designs that involve a straight-through water line
pattern, a simple, effective way to seal the line and prevent leakage is
electroless-nickel plate the water lines. In complex circuit-type patterns, it
is advisable to use an acceptable sealant such as Dichtol. Electroless nickel
has a tendency to pull away from sharp corners such as those at intersections of
crossing water lines. However minutely this pulling away from corners may be, it
will eventually cause some leakage into the material and reduce permeability
through oxidation. Improper use of the Dichtol sealant will produce the same
results. Regardless of which sealing process is used, be absolutely certain the
material has been thoroughly cleaned of any residual machining fluids or other
contaminants.

All technical and engineering data
and suggested procedures, specifications and applications contained in this
publication are for general information only. Sinto Steel, Molder's World, Inc.,
International Mold Steel and/or their distributors disclaim any and all express
or implied warranties of merchantability, suitability for any particular purpose
or use, or freedom from infringement of any patent, trademark or copyright.
Porcerax II® is a registered trademark of International Mold Steel, Inc. and
SintoSteel .
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