For buttress casing, API requires certain inspections that can align with Gagemaker’s recommended best practices.
Do a 1st article full inspection, including using an optical comparator and corresponding overlay, at least once per shift / per machine setup based on your QMS program. 
During full production runs, use the corresponding groove width Go/No Go gage part-to-part.
If a part fails the Go / No-Go inspection, then investigate further with the tooth thickness gage, TW-6001, or use an optical comparator and overlay to quantify the error and address the problem with the insert, cutting too, lathe etc.
