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Question about a sand mold blow I saw at the Tacoma foundry open house

They had a green sand mold fail right at the pour, and the floor supervisor pointed out a cold shut in the pattern nobody caught. I've been double checking my own patterns for that same flaw ever since. Has anyone else had a close call from a cold shut they missed?
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3 Comments
avery_flores
Caught a cold shut on a matchplate pattern last year after a similar scare. Started running my finger over every parting line before it goes to molding, feeling for that tiny ridge. It's saved two of my production jobs from a washout. That tactile check is now a non-negotiable step in my shop. What's your method for checking patterns?
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wren230
wren2301mo ago
My buddy Mike had a pattern blow a core because of a hairline crack nobody saw. He got so paranoid he bought one of those cheap USB microscopes off the internet. Now he zooms in on every vent and corner like a detective. Says it's like finding a whole new world of tiny problems before they become big ones. He caught a sand inclusion starting on a gear pattern last week that way.
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ramirez.vera
That finger check sounds smart, saves your eyes from missing what your hands can find. I mean, do you ever use anything like a thin feeler gauge for the really tight spots, or is it just the skin test? Idk, sometimes my fingers are too rough to feel a tiny lip.
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