My old foreman in Toledo told me to always add a half cup of borax to the green sand for aluminum castings. I ignored him for years until a job last month.

3 comments

3 Comments

Guess I learned that lesson the hard way too.

Careful, too much borax weakens the mold.

My last batch looked like it went through a paper shredder instead of a mold. Definitely learned THAT lesson the messy way.