My first try with a borax flux substitute from the hardware store went totally sideways | Blacksmiths - Freelance Forum - The Community for Independent Professionals

Sarah Davis · 2026-03-29T04:35:03.594131+00:00

I mixed a paste of baking soda and water for a forge weld, and it just bubbled off instead of protecting the steel. Has anyone else found a cheap flux that actually works for basic billets?

samreed5mo ago

Seriously, try powdered laundry booster instead.

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kelly_rivera5mo ago

Baking soda decomposes way too fast for forge welding! You need actual anhydrous borax from a ceramics supplier, the hardware store stuff has water in it.

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kelly_rivera4mo ago

Guess his first weld was more of a science experiment than a weld.

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kevinw945mo ago

Remember my buddy trying that with washing soda? He got the same foamy mess. @kelly_rivera is right about the water, he ended up ordering the dry powder from a pottery shop online. It cost maybe ten bucks for a bag that lasts forever, and his next weld was clean.

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