Forge weld flux

[ThomasPowers]

Note that if you are working with pattern welded billets for knives or art you do not want iron filings in the mix as it muddies the transitions.

Many people who are fluxless welders work primarily with low carbon steels as the high carbon or high alloy steels are much more sensitive to higher heats!

Can be quite difficult for a new person who doesn't realize the differences in welding for blades vs welding for "normal" objects and so tries the process for one with the other.

[wooginator]

Thanks for all your advice, everyone! In the end I bought a pound of EZ-weld Borax flux with iron filings from the blacksmithing site I use. I'm mostly just fooling around, so if I botch or irreparably mar a couple of pieces before I get the hang of it it's no big deal. In the future I'll just buy laundry borax though.

[CurlyGeorge]

For the money, plain old 20 Mule Team Borax works just fine. I have gathered saw cuttings from under my bandsaw and added them to the borax. I get basically the same thing that you just bought, for less $$. Works out well. I have two main containers to save clean saw cuttings in. One for mild steel and one for wrought iron. :D

[Nakedanvil - Grant Sarver]

Well, I prefer quantum flux.

[ThomasPowers]

Grant, how *is* your flux capacitor coming along these days?

[Nakedanvil - Grant Sarver]

I already answered that! But not yet!

[ThomasPowers]

I see; perhaps you should wear your *heavy* *coat* tonight...

[Frank Turley]

I've been forge welding, not pattern welding, for 48 years. For fagot welds, I use borax from the box. For lap welds, I use borax and the proprietary E-Z weld. When the borax melts and glazes the surface, it gets tacky, so when the E-Z weld is put on it, the E-Z tends to stick to it.

Borax is best applied with a spoon at an orange or lemon heat, so that it melts right away. If you dip the work in borax, the borax creates a circular glob of flux, not all of which melts. It's a mess. Best to use the spoon.

Some people wire brush before fluxing. Some don't. Some old timers just spoon it on while the pieces are in the fire.

Another good flux is "Black Magic" which is sold by Johathan Nedbor of Canal Forge in New York state.

[Steve Sells]

I strongly suggest 20 mule team. Have you ever noticed that most the people that advocate learning to weld with out flux are not the ones that do it that way themselves, but merely telling us about some one they heard about ?

Some I suspect may not even have ever welded, but just people telling what they heard, which really does not help the working people find out how to do a thing, it only muddy's the waters. Why make learning harder by avoid that which helps us???

For the record I use 20 mule team, for higher alloy I add 5% Boric Acid, and 5% Sal Ammoniac. and I have forge welded with out flux, but I am happier when I have it to use.

[thingmaker3]

Have you ever noticed that most the people that advocate learning to weld with out flux are not the ones that do it that way themselves, but merely telling us about some one they heard about ?

No. I have not. But I'll keep an eye out in the future, just in case.

And yes, I have welded mild steel without flux. I get about one "go" for every five or six "no."

[Dave Budd]

I picked up some more borax last week as my old stock was running low, and I noticed something a bit different about it. My old stuff was the remnants of some lab grade sodium tetraborate (so borax) from a chemical supply company; i've had it in my damp workshop for about 6 years and until recently haven't done much welding. The new stuff was a bag of sodium tetraborate decahydrate (again borax), from a jewelry supply company. I bought that stuff because it was a big and reasonably cheap bag that was real Borax rather than 'borax substitute, which is all I can get around my way these days.

The odd thing I noticed was that the older stuff, when coming up to temp in the gas forge wriggles around on the surface of the metal giving me an idea as to how close to temp I am. The new batch melts to the glassy barrier but never bubbles or moves, even when the metal is moe than hot enough! Not a probem and it hasn't affected my welding (only been working on high carbon and HC to mild with it so far), but I'm just curious as to why it doesn't move on the surface?

[Steve Sells]

I picked up some more borax last week as my old stock was running low, and I noticed something a bit different about it. My old stuff was the remnants of some lab grade sodium tetraborate (so borax) from a chemical supply company; i've had it in my damp workshop for about 6 years and until recently haven't done much welding. The new stuff was a bag of sodium tetraborate decahydrate (again borax), from a jewelry supply company. I bought that stuff because it was a big and reasonably cheap bag that was real Borax rather than 'borax substitute, which is all I can get around my way these days. The odd thing I noticed was that the older stuff, when coming up to temp in the gas forge wriggles around on the surface of the metal giving me an idea as to how close to temp I am. The new batch melts to the glassy barrier but never bubbles or moves, even when the metal is moe than hot enough! Not a probem and it hasn't affected my welding (only been working on high carbon and HC to mild with it so far), but I'm just curious as to why it doesn't move on the surface?

They have differing amount of water bound up in the matrix, the term decahydrate is for 10 units of water, whixch is the more natural state for borax to be found. The other was initially lacking this, also called anhydrous borax, but after time I suspect it has picked up some water from atmosphere.

[backshopknives]

i have been having some trouble with making damascus im not sure if its the flux im using or what. i curently use a cheap wal-mart brand of borax. i dont know if this is the problem or what. i have heard of using beach sand for flux. let me know what i need to do differant thanks guys.

[pkrankow]

What metals are you using?

Is the ingredient list on the flux you are using "borax" and maybe an anti-caking agent? If there are any soaps or other funky stuff in it that is not the product you want. Get the "20 mule" brand of borax, it is not expensive and I last bought it at Walmart, or Meijers, or Kroger... Most "grocery" stores with a laundry section carry it.

Borax melts at a lower temperature than silica sand. Boric acid melts at a lower temperature than borax. Using a mixture of agents can help because one agent will work at a different temperature range than the others. Boric Acid can be found as 98% concentration in roach powders, look up the other names for boric acid before going shopping.

The thread Steve linked is well worth the read.

Phil

[ThomasPowers]

Since you can forge weld without flux if you are having difficulties it may be due to other issues.

Note that leaf spring to leaf spring or BSB to BSB can be a bit harder to get a weld than with those alloys to a plain steel.

Can you tell us what you are using and what the problems you are having?

Note that clean quartz sand or powdered glass were fluxes used with real wrought iron which is almost self fluxing and survives very high temperatures in the forge. Using them to weld up modern alloys is sort of like using modern gunpowder in antique firearms!

[backshopknives]

im using old bandsaw blades and bike chains for the metal and cheep wal-mart 20 mule team borax. i got the steel to a almost yellow color. i also used alot of flux, but when i hit it all just kinda fell apart. i was using a 32oz ball pein hammer. so hope that helps. thanks guys.

[MattBower]

If you're saying the steel crumbled when you hit it, you may have overheated it. Welding temp varies inversely with carbon content (more carbon = lower welding temp), and some steels don't respond well to being forged outside a narrow range.

When you say the steel was at "almost" a yellow color, what kind of ambient light are we talking about? Dimly lit shop? Bright sunlight? It makes a tremendous difference.

[ThomasPowers]

20 muleteam borax is 20 muleteam borax no matter who sells it.

I assume you have forge welded simple billets before with no problem?

Otherwise this is rather like "I've never danced before so how am I messing up the lead in the Nutcracker?"

Try a bandsaw blade and pallet strapping billet making sure each layer of BSB has one of PS between it and the next one.

Are you welding in a charcoal, coal, coke or propane or NG forge?

Is your anvil and tools close to the forge and preheated?

[Steve Sells]

Did you grind the flats clean before trying to weld, or assume the crud, blackening, scale, etc will evaporate in the forge? I have known people to try to forge weld cable with out even removing the asphaltum first (not a good idea, but they saw on You tube.. they ended up leaning the hard way.)

Clinkers can kill a weld.

[John B]

Did you hit it too hard ?

[Drewed]

I have found that chain saw chain ( and therefore assuming bike chain ) will crumble when hit if over heated. Also the fact that the chain like to move makes it a lot harder. I've read about people sticking the chain together with a welder before bashing it down into a billet. I haven't tried it, but then again I haven't gotten a chain to weld either!

[backshopknives]

i use a coal forge and my anvil is close to the forge but i dont preheat it. i work outside in the sunlight most of the time.

[MattBower]

"Almost yellow" in sunlight is probably too hot. The traditional blacksmiths' color descriptions seem to assume a relatively dim shop, at least in the immediate area of the forge. Was the steel sparking when you pulled it from the fire?

[backshopknives]

no it was not sparking

[MattBower]

That's good. I still think it's likely that you tried to weld at a temp too high for that steel. Consistent lighting -- preferably with decent shade -- will help you judge color. Some folks who work outside build a hood over the forge to deal with the problem.