unbalance sensitivity

[CH5OH]

would a casted impeller on a single wheel, overhung compressor be (less,equal,more) sensitive to unbalance due to fouling, compaired to same compressor but with machined impeller (less required balancing holes/weights)?

 

[Ralph2]

A poorly cast (porosity / bumps) impeller would be more likely to aquire deposits if the pumped media was contaminated I would think. The variable friction of a cast impeller would also contribute to an unbalance, if one started splitting hairs, so to speak.