Batch consistency relies on three principles: fixed parameters, standardized loading, and complete process documentation.
Lock in critical process parameters during pilot testing — temperature, time, atmosphere, loading amount. Then execute production batches using identical parameters. If parameters change every run, consistency is impossible.
Loading method standardization matters too: how much, how arranged, which crucible — all should be documented and repeated.
Skipping pilot testing for direct production? Only recommended if you're already confident in your process.