Lost Foam Casting Tolerances
In general, a linear casting tolerance standard of ±0.005 inches / inch is achieved in the lost foam casting process, but is also influenced by the part material, its size, geometry and complexity.
Coining or straightening processes within lost foam casting will help to achieve tighter tolerances to be held at critical dimensions. With a combined effort between the foam pattern maker, the caster and the client , may result the reduction or elimination of other machining needs.
The tool complexity and pattern age control must be designed in such a way as to meet the client's (or end user's) needs. Designs need to be in form, fit and function, keeping in mind the capabilities of the lost foam process.
As the mold walls do not move, this process is capable of producing close dimensional tolerances, and enable the flow of material through difficult internal as well as connecting passages. Able to deliver casts that has a high core content, component integration, internal complexity and high machining content, casts have a high internal integrity, a good pressure tightness as well as the capability of reducing or eliminating further machining processes.
Lost Foam Casting Tolerance Standard
Used for critical application, parts casted using this process can be found in automotive parts, the marine and aerospace industries, as well as the construction industry.
In Inches:
Note: You can click on the table below to view a larger image.
In Millimeters:
Note: You can click on the table below to view a larger image.
Note: Numbers rounded off to nearest decimal.
Generic Tolerances
Note that in cases where diameters are split by glue lines, 0.005 inches (0.127 mm) to 0.010 inches (0.254 mm) should be added, depending on the foam size.
Note: You can click on the table below to view a larger image.
Note: Numbers rounded off to nearest decimal.
Flatness Tolerances
Note that flatness can be affected by:
- The thickness of the foam,
- The foam's geometry,
- The foam removal process, and
- The control in the molding cycle
Note: You can click on the table below to view a larger image.
Note: Numbers rounded off to nearest decimal.
Linear Tolerances
Note: You can click on the table below to view a larger image.
Note: Numbers rounded off to nearest decimal.
Back to Main Page: Lost Foam Casting
Further Suggested Reading:
- How Lost Foam Casting Works
- Metals that can be Lost Foamed
- Problems of Surface Carbon in Lost Foam Cast Parts
- Surface Finish for Lost Foam Cast Parts