The impeller can be machined from solid using NC machines, in much the same way as that of a centrifugal design.
ðɪ ɪmpˈɛlɚ kæn biː məʃˈiːnd fɹʌm sˈɑːlɪd jˈuːzɪŋ ˌɛnsˈiː məʃˈiːnz, ɪn mˈʌtʃ ðə sˈeɪm wˈeɪ æz ðæt əvə sˌɛntɹɪfjˈuːɡəl dɪzˈaɪn.