The groove thief consists of a hollow sleeve (1 in. in diameter) surrounding a solid inner steel rod with a groove bored along most of the length of the pipe (19). The inner pipe has a sampling cavity that is ~1/2 in. deep and wide along the middle 80% of the rod. Rotating the inner pipe relative to the outer pipe opens and doses the sampler. The sampler is inserted into the powder bed while open; rotating the inner tube traps material within the sampler
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