Casting
Buyer's Guide
Investment Casting
Surface Finish
Metal mold makes wax replica. These are sprued, then surrounded with investment material, baked out, and metal poured in resultant cavity.
63-125 RMS
Metals
Size Range
Tolerances
Part Price
Design Freedom
Most all castable metals
Fraction of an ounce to 200 pounds, up to 48"
±.005" per inch. Minimum ±.003"

Draft Requirements
Normal Minimum Section Thickness
Ordering Quantities
Normal Lead Times
None
Aluminim Alloy .020"
Beryllium Copper .030"
Stainless Steel .050"
Carbon Steel .050"
Any Quantity
Samples: 3-8 weeks
Production: 3-7 weeks
Powder Metal
Surface Finish
Metal powder is compressed in die barrel between moving upper and lower punches. Lower punch ejects part, which is then sintered, and sized if close tolerance is required.
Equivalent to 16-90 RMS in solid metals
Metals
Size Range
Tolerances
Part Price
Design Freedom
Iron and Iron alloys.
Copper, Bronzes, Brass.
316 Stainless Steel, Monel
Limitation on surface area - up to 20 square inches ferrous, higher for non-ferrous.
Sized: ±.0005" per inch.
Unsized: ±.004"
Direction of pressing: ±.005"
Draft Requirements
Normal Minimum Section Thickness
Ordering Quantities
Normal Lead Times
Usually none
.030" - .090"
(Depending on density and length ratio)
Usually 2,000 and up. Larger parts sometimes as low as 500.
Samples: 6-14 weeks
Depending on part complexity.
Plaster Mold
Surface Finish
Cope and Drag Method (using fine plaster for mold and cores). Plaster slurry is poured onto pattern halves, allowed to set then mold is removed from pattern, baked, assembled, and metal is poured into resultant cavity.
63-125 RMS
Metals
Size Range
Tolerances
Part Price
Design Freedom
Aluminum, Brass, Bronze, Zinc, Beryllium, Copper
Normally up to 800 square inch area. Some foundries capable of larger sizes.
One side of parting line ±.005" up to 2". Over 2" add ±.002" per inch. Across parting line ±.010". Allow for parting line shift of .015"
Draft Requirements
Normal Minimum Section Thickness
Ordering Quantities
Normal Lead Times
External: 0° - 1/2°
Internal: 1/2° - 2°
.060"
Aluminum: usually under 2,000
Copper base: Any quantity.
Samples: 3-15 weeks.
Production: 4-8 weeks.
Die Casting
Surface Finish
Molten metal is injected, under pressure, into hardened steel dies.
32 - 90 RMS
Metals
Size Range
Tolerances
Part Price
Design Freedom
Aluminum, Zinc, Magnesium and limited Brass
Not normally over 3 feet square. Some foundries capable of larger sizes.
±.0015" per inch. Not less than .002" on any one dimension. Additional .010" on dimensions affected by parting line.
Draft Requirements
Normal Minimum Section Thickness
Ordering Quantities
Normal Lead Times
1° - 3° Aluminum
1/2° - 2° Zinc
.060"
Usually 500 and up
Samples: 8-16 weeks
Production: 2-6 weeks
Permanent Mold
Surface Finish
Molten metal is gravity poured into cast iron or steel molds, coated with ceramic mold wash. Cores can be metal or sand.
Aluminum: 150-200 RMS
Iron: 200-350 RMS
Metals
Size Range
Tolerances
Part Price
Design Freedom
Aluminum, Brass, Bronze, and Cast Iron
Limitation mainly foundry capabilities. Aluminum: Usually 1/2 pound to 100 pounds. Iron: 50 pounds max.
Aluminum: Min. ±.010" up to 1", or ±.015" if across parting line; add ±.002" each add. inch. Iron: ±.032" all directions.
Draft Requirements
Normal Minimum Section Thickness
Ordering Quantities
Normal Lead Times
  • Aluminum: Outside 2° min. (3° desirable)
    Inside 2° min.(4° desirable)
  • Iron: Outside 3° Inside 7°
Aluminum: .100" for small areas, up to 3/16" or more for larger areas.
Iron: 3/16" for small areas, 1/4" normal.
Usually 500 and up.
Samples: 6-14 weeks
Production: 2-6 weeks
Resin Shell Mold
Surface Finish
Cope and Drag Method. Resin coated sand is poured onto hot metal patterns, curing into bonded sand shell mold halves. These are removed from pattern, assembled with or without cores, and metal is poured into resultant cavities.
Aluminum: 150-200 RMS
Iron: 200-350 RMS
Metals
Size Range
Tolerances
Part Price
Design Freedom
Most all castable metals.
Normal maximum 550 square inches usable mold area.

Ferrous ±.008" per inch up to 3". Add ±.005" per inch over 3 inches.
Non-Ferrous: Under 1" ±.004"-.006"
Under 3" ±.005"-.010"
Under 6" ±.008"-.013"
Under 12" ±.015"-.020"
Add ±.005" to .010" across parting lines.

Draft Requirements
Normal Minimum Section Thickness
Ordering Quantities
Normal Lead Times
Outside: 0-1°
Inside: 0-2°
3/32" Non-Ferrous
1/8" Ferrous
Ferrous: Usually 250 and up
Non-Ferrous: Any Quantity
Samples: 4-10 weeks
Production: 2-4 weeks
Sand Casting
Surface Finish
Cope and Drag Method. Tempered sand is packed onto wood or metal pattern halves, removed from patter, assembled with or without cores, and metal is poured into resultant cavities. Various core materials can be used.
Non-Ferrous: 150-350 RMS
Ferrous: 250-500 RMS
Metals
Size Range
Tolerances
Part Price
Design Freedom
Most all castable metals.
Limitation mainly foundry capabilities. All sizes.
±.032" up to 3"
±3/64" from 3" to 6"
±1/16" above 6 inches.
Add ±.020" to ±.060" across parting line.
Draft Requirements
Normal Minimum Section Thickness
Ordering Quantities
Normal Lead Times
1° - 5°
Non-Ferrous: 1/8" - 1/4"
Ferrous: 1/4" to 3/8"
All Quantities
Samples: 2-6 weeks
Production: 2-4 weeks
Select a Casting Process from the list above for an overview of each process.
  • FAI represents leading sources for castings by every process described here. Working with us to select the most practical and economical process translates to lower production costs. Expensive secondary operations are minimized or eliminated, and you save the time and trouble of investigating and solicting quotes from many vendors.
  • You benefit from our unique approach - our goal is to match your need with the most appropriate casting technique, rather than compromising your intent and modifying your design for one particular process. A Foundry Associates engineer can work with your team while the design is on the drawing board. Our expert impartial analysis tranlates into a better design and bigger savings for you.

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