patb12•1mo ago

TIL a simple tweak from a guy in Ohio fixed my forge welding issue

I was having trouble with forge welding for nearly a year. My welds kept falling apart or looked crumbly. I posted about it on a forum and a smith from Ohio said "your flux is too wet, dry it out on the anvil first." I tried heating my borax a bit before applying and the difference was night and day. My last three welds held solid with no delamination. Has anyone else run into flux moisture causing issues?

3 comments

3 Comments

davis.noah1mo ago

Oh man, that's a good one but I gotta gently push back on something. It's not that your flux is "too wet" exactly, more like the moisture is flash boiling under the flux layer and blowing your weld apart from the inside. I've had the same headache and found that preheating the flux on the anvil works, but you gotta get it just past where it stops bubbling. If you go too hot it turns into that glassy crust that doesn't stick right either.

jennyp1917d ago

Thing nobody talks about is how your flux storage matters just as much as preheating. Kept mine in a beat up coffee can for years, always had issues. Switched to a sealed mason jar with one of those silica packets thrown in. Night and day difference. Even flux that looks dry pulls moisture out of humid air if it sits out.

grant.sam1mo agoProlific Poster

Tbh, I feel that pain way more than I'd like to admit. That flash boiling thing drove me nuts for a couple months before I figured out preheating was the fix. I used to just dump dry flux straight from the container and wonder why my welds were popping like popcorn. Getting it past that bubble stage without turning it into a glassy mess is such a fine line to walk.