Warning: My old method for checking core sand moisture was way off

An inspector from the Cleveland plant told me my 'hand squeeze' test was letting through sand that was still at 4% moisture, which explains the gas holes we kept seeing. I switched to using a proper Speedy moisture tester for every batch now. Anyone else have a simple tool that saved them from a recurring defect?

3 comments

3 Comments

hollym123mo ago

That Speedy tester is a lifesaver for sure. I remember we had a similar issue with green sand, not core sand, but the idea is the same. Our old shop used the "ball test" where you squeeze it in your hand. We thought a good ball that held its shape was around 3% moisture. Brought in a proper tester and found out we were off by over a full percent sometimes. It's crazy how much your hand can miss, especially with different sand mixes. Switching to a real tool for every batch was the only thing that fixed our consistency problems.

oliver2423mo ago

A buddy of mine ran into that exact hand-test problem, @hollym12. His crew was getting bad shakes until they finally bought a proper moisture meter. The difference in their castings was night and day once they had real numbers to work with.

faith_perez14d ago

The hand squeeze test is definitely one of those things that seems good enough until you realize how much money it's costing you in scrap! We had the same rude awakening with our green sand a couple years back. Thought we were around 2.8% moisture based on feel but the Speedy meter showed we were bouncing between 3.5% and 5% depending on the batch. That explains why some cores were soft and others were hard as a rock. It's wild how your hand can be off by that much just because the temperature or the sand type changes even a little. Now I won't run a mix without checking it with the meter first, no exceptions. Honestly feels like one of those upgrades you kick yourself for not doing sooner.