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Update on my sand ramming technique from a guy in Toledo
A guy from a shop in Toledo saw me working on a small gear pattern last month and said, 'You're hitting it like you're mad at it, you're just making it harder.' He told me to use three firm, even hits with the rammer instead of a bunch of hard ones. I tried it on a batch of twenty molds for some pump housings, and the sand density is way more even now. It also cut down my ramming time by a good chunk because I'm not fighting the sand as much. Has anyone else had a similar tip for getting better mold hardness without the extra work?
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pat_stone2mo ago
What kind of rammer were you using, like a peen or a flat base?
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paulw532mo ago
My old shop teacher swore by a 1-inch peen for green sand, but he was packing for speed, not even density.
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emery2902mo ago
That point about not fighting the sand really hits home. I was always taught more force equals better hardness, but it just makes the sand lock up. Pat_stone asking about the rammer type makes me wonder if the shape of the peen actually causes that uneven packing you were seeing before. A flat base might spread that firm pressure out better for those three even hits. It's one of those simple changes that seems obvious once you hear it.
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