Metal Penetration
Technical Support
Struggling with a specific casting defect or just need general technical support?
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Irregular metal formation; typically in slots, holes, passages or tight areas
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Indicates that the metal broke out, or penetrated the ceramic shell
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Usually due to the fact that the shell is typically too weak (due to structure or dryness) to adequately hold the metal in the desired shape
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Often referred to as birdnesting when it appears in corners
Causes of this defect are evident in the shell and other portions of the process; to cure, R&R recommends taking the following actions:
Shell
Weak spots in the ceramic shell due to difficulty of buildup in details.
Improper shell build in the detail area.
Insufficient or poor shell drying.
Excess slurry and/or stucco left behind.
Other
Rapid depressurization of autoclave.
Depressurize from maximum pressure to atmospheric gradually over about 2 minutes (evaluate autoclave operating parameters).