User manual

Z Corporation Z406 System User Manual
62 Z Corporation Service [phone]/(877)88-ZCORP
6.6 INVESTMENT CASTING
Z Corp. parts can be used as investment casting patterns to quickly get metal parts. Starch-based
parts can be infiltrated with cyanoacrylate resin or wax and used instead of a standard wax pattern in
the investment casting process. The parts burn out well and do not have any expansion problems
that would lead to shell cracking. Investment casting of Z Corp. parts is a good way to get a final
prototype, or a near-net shape part made of the specific alloy your application requires. It can also be
used for short-run production when time is extremely important. 25% of Z Corp. users have had a
part cast at some point in their design process.
General Notes
Consult with experienced foundry personnel to incorporate best practices in casting design when
designing your pattern. They will help the designer or engineer to design their part with the gate,
runners and secondary operations in mind. Operations and equipment vary from foundry to foundry.
Success has been achieved consistently in a variety of situations and locations using the notes below
as a guide. Steps that have been varied to achieve success are noted.
Preparation
1. Starch-based powder parts should be used. Oven-drying the part at 104
o
F (40
o
C) after removal
has been included in the process at some locations, especially where humidity may be an issue
with ‘green’ part characteristics. Additional gate(s) may be incorporated in the set-up of the mold
to increase air flow during burn-out of the casting pattern.
2. Patterns should be infiltrated with either wax or resin. Wax infiltration is an excellent treatment for
investment casting patterns. Wax infiltrated parts will behave similarly to common wax patterns
when they expand. The ZW4 or ZW3 Waxer and hand application methods have both been
successfully used on Z Corporation parts. Some users briefly blast their parts with a consumer
hairdryer or heat gun to quickly heat and re-cool the wax to improve surface finish.
Patterns can also be infiltrated with resin for increased strength. Surfaces should be sanded to
their desired finish after this step. Then coat with wax.
Casting
1. Z Corporation patterns can be assembled on standard wax gates and runner systems. They
should be coated with the normal 6-8 shell layers of slurry.