Unpopular opinion: I figured skiping the mold coat was fine until a casting fused to the sand

That mess made me see a thin layer saves the whole job... won't skip it again.

3 comments

3 Comments

Is the mold coat really the only thing stopping a fuse? I've seen casts stick even with a good coat when the sand was too damp. @nora_hart95 mentioned the thin layer doing work, but in my experience, the sand quality and moisture play a bigger part. For example, last month we had a fuse because the sand wasn't packed right, not from missing the coat. So skipping the coat is bad, but fixing the sand is just as key.

nora_hart951mo ago

That thin layer doing all the heavy lifting...

christopher59424d ago

Hold on, you can't just blame the sand every time. That mold coat is the main barrier against metal penetration, period. I've seen bone-dry, perfectly packed sand still fuse if the coat was too thin or missed a spot. The metal looks for any weakness, and that first layer is what it hits. Saying the sand is just as key lets people get sloppy with the coating step, which is way more important.