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Can we talk about the time a core shift ruined a whole pour at the old Milwaukee plant?
We were about halfway through a 500-pound bronze pour for a custom gear blank when I saw the core box had shifted a quarter inch, so I yelled to cut the flow and we spent the next three hours chipping the mess out of the flask before the boss even got off the phone with the upset client.
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barbara846mo ago
Our shop had a trainee who mixed the core sand wrong, like way too much binder. Thing was a solid rock. We didn't know until the shakeout, took us a full eight-hour shift with jackhammers just to get the core out of a simple pipe fitting. Felt like archeologists, but for our own dumb mistake.
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leow906mo ago
Man, that sound brings back a bad memory. We had a greenhorn forget to vent a core once and the whole thing basically EXPLODED when the hot metal hit the trapped air. It wasn't just a ruined pour, it was a safety nightmare with molten splatter everywhere. The cleanup took two days and they had to repaint a whole section of the ceiling. Just a total mess from one skipped step.
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umaanderson5mo ago
Actually those green sand cores with too much binder are a different beast than a core shift. A shift happens when the core floats or moves in the mold during pour, not from bad mixing. I've seen a core shift on a valve body pour where the print wasn't weighted right and the whole thing lifted up a good half inch. We ended up with a casting that looked like a sideways banana instead of a flanged pipe. The tracer dye in the x ray test showed the cavity was totally off center. That kind of mistake is just gutting because its so avoidable with simple checks.
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