INSTRUCTIONS

OMNICAST-LP is a hard high-heat phosphate bonded casting investment for solid mold castings. It can also be used for castings in nickel and cobalt based superalloys alloys.as well as gold, palladium, platinum and other non-precious alloys. A multi-purpose investment, OmniCast is used in dental and jewelry castings. It can be used for centrifugal, vacuum assist or vacuum chamber casting. A special liquid is available for dental applications to provide controlled expansion required for other applications such as Crown & Bridge castings.

1. Properties (Determined at w/p of 28/100 and at 72F/22C.):
Water to Powder Ratio: 28-30/100
Working Time: 6-8 minutes
Setting Time: 15 to 25 minutes
Setting Expansion: 1.2 % with liquid
Setting Expansion: 0.5 % with water
Hygroscopic Expansion: 0.5 %
Thermal Expansion: 1.8 %
Compression Strength at 60 minutes: 250 PSI

The temperature of the powder, room and mixing fluid ( water or special liquid ) affects the working and setting time of the investment very significantly. For best results the work time of 7 to 8 minutes should be kept by adjusting the temperature of mixing liquid. A colder temperature will lengthen the work time. A warmer temperature of water or liquid will shorten the working time.

2. Storage
Always store in a dry environment. After use, collapse poly-bag against the powder to expel all air. Close lid tightly.

3. Patterns
It is a good idea to clean patterns with a good debubblizer like Emdin's MAXIFILM to minimize bubbles on the casting even though Omnicast will by itself minimize bubbles due to its smooth consistency, flow and micro-fine grain structure.

4. Sprueing and Gating Patterns
Use standard sprueing and gating techniques. Leave at least 3/8 inch (10 mm) space from the top and sides of the flask. The vent rods, if used, should be at least 10 mm away from the patterns.

5. Flasks
Solid and perforated flasks may be used. Always use a collar, 1 1/2 inch height, of paper/tape or rubber above the flask to allow for vacuum rise.

6. Mixing Ratios
Always add powder to water. Weigh powder accurately and measure water correctly. The recommended ratio for OmniCast is 28 to 30 parts of water to 100 parts of powder, by weight. The use of liner for jewelry castings is not necessary.

Non-Precious Alloys: Liquid = 80% Water = 20%
Precious Alloys : Liquid = 60% Water = 40%

W/P ratio= 28/100
Powder wt., lbs.	Water oz	Water ml.	Powder wt., kg	Water ml.
1	4.5	127.0	1	280.0
5	22.4	636.0	5	1400.0
10	45.0	1271.0	10	2800.0

To determine the number of pounds of investment needed to fill a flask, multiply the flask volume (cu. in) by 0.05.

To determine flask volume in cubic inches:
   * Volume of round flask=0.7854 x Diameter (squared) x Height
   * Volume of square flask= Width x Length x Height

ADJUSTING EXPANSION:

To INCREASE expansion: Use full strength liquid or use high expansion liquid and/or use softer waxes.

To DECREASE expansion: Use less liquid and more water keeping the total same.

7. Directions
Hand mixing: 30-45 seconds
Machine mixing: 60-120 seconds
Hold under vacuum: 30-40 seconds
Vacuum bowl: 60-90 seconds
Vacuum flask: 60-90 seconds

All steps should be completed before 5 1/2 minutes have elapsed from the start of hand mixing. Use colder water to lengthen the working time if the steps can not be completed as specified.

Note: The temperature of the investment in the flask after investing will begin to rise as the investment begins to set. This is normal characteristic of the investment. Do not disturb the flask until the investment has completely set. Leave the invested flask on the bench for at least 30 minutes before beginning to dewax.

Wax Elimination: OmniCast can be steam dewaxed. A chamber pressure of 10 psi should be sufficient to achieve.

After removing the sprue base and collar, the flask should be stacked, using pyramid method, with enough room available for adequate air flow to allow the removal of moisture.

Burnout Procedure: The flasks should be heat soaked at 200 to 250 degrees Fahrenheit for about 60-120 minutes. This is very important to minimize finning and flashing on the castings. The moisture should be removed slowly and gradually. Too fast a heating in the beginning can cause cracking in any investment.

After soaking for about two hours, raise the temperature slowly to 500-600 degrees F. Hold at this temperature for 3-5 hours for thermal reaction to start. Then raise temperature gradually to 1000 degrees F, heat soak for 2 hours, raise again to 1600 degrees F, heat soak for 2 hours and cast.

Note: For applications requiring higher strength heat the invested flask to 1800 degrees F and use the special liquid formulated to improve the fired strength of the investment significantly.

Devesting: Quenching the flask in cold water will shatter and thus remove most of the investment. However, consult alloy manufacturer first because some alloys will not permit this procedure.

Cautions: OmniCast can retard the setting of the Gypsum investments. When using gypsum investments, such as SUPERCAST, SUPERCAST-20, or MK 90, the investing area should be kept separate. If the mixing equipment is shared, clean the equipment extremely fully after it has been used for OmniCast.

WARNING
OmniCast contains silica. Inhalation of dry powder can be hazardous to your health.