tecnovist

Forge weld flux

Recommended Posts

Hate to say it, but it depends what you're welding. For wrought iron and mild steel, when the flux is bubbly and smokey when you pull the piece from the forge, that's a very good sign. Welding temps for higher carbon steels are somewhat cooler than wrought or mild. But I still have problems welding those steels sometimes myself, so I'm not the right guy to give advice on that.

You can also use a probe to test welding temp. Take a piece of baling wire or a small diameter rod with the end forged to a point. Get it hot, put a little flux on it, and touch it to the work piece in the forge. When it wants to stick -- firmly -- to the work, you're about where you need to be. (Thicker work may need to soak a little to let the interior temp catch up.)

Share this post


Link to post
Share on other sites

Colour perception is different from person to person. You would need to see it in person to know what colour is appropriate especially as digital cameras also skew colours!

Share this post


Link to post
Share on other sites

Color perception is different for the same person (me) under different conditions. If I am in full daylight, overcast, under shelter, at night under artificial lighting, sick, etc. I perceive colors vastly different. With a head cold dull red and yellow are the same color to me.

Phil

Share this post


Link to post
Share on other sites

New guy to the forum. I was taught the blacksmith trade by a old timer in his early 70's at the time. He taught me to forge weld using baking powder. I was wondering what everyone else uses for flux or do you have your own formula?

Share this post


Link to post
Share on other sites

Twenty Mule Team Borax or pure white sand from the Kaw River by Fort Riley Kansas. Live in Oregon now and borax has stood me well for over forty years. If everything feels clean I use no flux sometimes. Eric Sprado

Share this post


Link to post
Share on other sites

Started with 20 Mule team, tried Easy Weld but it left a dirty looking joint. Use Larry Zoeller's Z-weld now, and it is best I have found.

Share this post


Link to post
Share on other sites

In 1987, I was demonstrating for the Northwest Blacksmiths Association at Darryl Nelson's forge in Eatonville, WA. Darryl said that he wanted to show me something. He had a bricked-up ziggurat gas forge with squirrel-cage blower, and we could separate some bricks on the side to make an aperture for looking inside, assuming we were wearing a face shield. A forge weld was going to take place. Darryl put some borax on the orange hot steel, and he followed this by putting E-Z Weld proprietary compound on top of the glazed borax. He said that the borax, when molten, became tacky (gummy) and that the E-Z would adhere to the borax with less chance of it falling off or loosening in the fire. He said that by watching carefully, one could tell that the iron filings in the E-Z would melt. At that point, the pieces could be withdrawn and welded on the anvil. It worked.

I protested a little. I said, "You can't mix the two fluxes together; E-Z Weld is made by the Anti-Borax Company!" But face it, Anti-Borax was a trade name chosen, so that the blacksmithing populace would, hopefully, NOT purchase any borax. I asked Darryl whether that would work in a coal forge. He said that he didn't know, because he had only tried it in a gas forge.

I am here to aver that I have used this method on lap welds ever since that time. It seems to help, even in a coal forge situation. For fagot welds, I use plain borax, because the degree of difficulty is less than when bringing two pieces together in a lap weld. I have found that when lap welding, one must repeatedly practice getting the pieces to the anvil, positioning them, and using the correct force when hitting them'

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

I started out forge welding in the early 1960's at Oregon State Horseshoeing School (no longer existing) on the OSU campus in Corvallis. Our instructor was Charles "Dick" Dickenson. The first thing that he had us do was to forge weld two old, used horseshoes together as a fagot weld. Both shoes were straightened and one bent flat into a U-shaped hairpin and then squeezed by hammering over the end of the other straight shoe. This gave us three layers to weld. The tongs would be on the end of the middle bar which protruded as a tongue from the package. We used coal forges, and the coal was quaility coal. We were to attempt to get the weld and to also forge the resulting bar into 5/16" x 3/4" hoeseshoe stock at the same time. Then, we had to bend it into a horseshoe shape. No flux was allowed. There were twelve of us in the class, and you never saw so much struggling and cussing. We all realized that this was a humility exercise. I got mine finished after 1½ days. It was a cheesy job and portions of it looked as though the rats had been chewing on it. Dick acceped it only because we had to go on to "greater things" in the curriculum.

I learned later that this exercise was termed a 'horseshoe sandwich' and was used at the Ft. Riley, Kansas, U.S. Cavalry horseshoeing classes. I heard that Frank Churchill was the founder of the school in the early 1900's. I was told that Churchill would first demo for the students the forge welding of a big bundle of baling wire into solid horseshoe stock. This was one example of what the Army called a "field expedient." Fortunately, Churchill did not make the students try that exercise, but he did have them forge weld a horseshoe sandwich.

Share this post


Link to post
Share on other sites

I used to buy the stuff, now I make my own.
40% fine silica sand (you can get this from some construction supply companies)
40% slaked borax (20 mule team borax that's been baked at 250 for about an hour)
20% iron filings (not, I repeat NOT steel filings.)

It's as good as most of the commercial fluxes out there at 1/5th the cost.

Share this post


Link to post
Share on other sites

I mostly use anhydrous borax (available from chemical supply houses) but when I used to weld reins on some tongs I made for a customer from 1045 I found the ez weld helped with making the weld disappear and stick a little better.

A retired steel mill blacksmith who stops by my shop regularly told me a while ago that they used to buy the ez weld by the 50 gallon drum. They would go through a drum every few months. This was back when they forge welded all their chain slings and they even made a lot of their own chain. He has told me of spending days working with a striker cold cutting 3/4" round bar to make chain.

Share this post


Link to post
Share on other sites

I use 20 muleteam borax mixed with roach-pruf (98% boric acid) as I generally am welding up billets with some Ni content and the boric acid seems to help.

Spikeknife----Iron filings: cast iron or wrought iron? (I assume cast iron was intended and have you tried brake lathe swarf for that?)

Clean quartz sand or powdered glass was the flux of choice for welding real wrought iron which is pretty much self fluxing and deals well with high temps that will burn modern steels. IIRC "Practical Blacksmithing" has a discussion on having to switch fluxes as they moved from real wrought iron into using Bessemer Steel---AKA mild steel

Share this post


Link to post
Share on other sites

I like Swan Forge Magic Weld but it is expensive. I also use 20 mule team. My mom's uncle (been gone 40 years) used to use mud dauber nest I have used it and it is pretty good. collect them in the winter when they are empty grind them imto a fine power. works pretty good. And NO I don't know what kind of mud it is made from.

Share this post


Link to post
Share on other sites

Hi All,
Spent most of Sunday working on my forge welding skills. I decided to do one of the lessons in Mark Aspery's second book-the one where you weld a bunch of leaves to each other ,then to branches. Admittedly, my welding skills are not what I'd like them to be. I am a pretty good smith, but not as good as I'd like to be. To get to the point, I've been using a blacksmiths flux reputed to have almost "magical" properties. I was struggling getting welds to take using this flux-2-3 tries each before it would weld. To make a long story longer, I got ticked off and went and got some good old fashioned borax straight out of the box (want to get some strange looks-go to the grocery store Sunday, right about when folks are getting out of church, when you're covered in dust and smell like coal and sweat). Guess what? Instant success-I could see the borax turning liquid and covering the welds way better than the other flux. I was able to weld at a lower heat, with all the welds taking on the first try. Moral to the story-guess what I'm going to keep using?
Maybe you all who are more proficient than I can tell what you use successfully with good results.

Share this post


Link to post
Share on other sites

Just plain ole Borax from the box. That's all that I normally use. I've tried adding metal shavings, or saw dust, that I collect in a container from under my metal cutting band saw. But I prefer just plain ole Borax. :)

Share this post


Link to post
Share on other sites

I say use what works for ya, I use anhydrous borax from the local clay art store, it works well for me, others swear by other things. If it aint broke dont fix it sorta thing.

Share this post


Link to post
Share on other sites

"blacksmiths flux reputed to have almost "magical" properties"

So what was this magical flux? Are you sure you got the formula correct? Was it given to you by a blacksmith, or, shudder, the Internet?

Share this post


Link to post
Share on other sites

I've tried borax and all the commercial brands and like Mustad's "SureWeld" best of all for ornamental iron. People who do a lot of pattern welding likely use borax on billets because it's cheap but my little can of SureWeld has lasted me over 5 years and I do quite a few small welds (leaves and scrolls and such).

Share this post


Link to post
Share on other sites

I had bad luck with borax when I first started, but having zero clue what I was doing (I have about one clue now!), I'm sure the flux wasn't to blame. My friend brought over some flux he got that was borax mixed with iron filings, and we had a lot of success with that. Since then I've mostly used straight borax, and my success rate with simple welds (mostly faggot welds) has been pretty decent. I'll probably just keep using borax since it's readily available and doesn't require any mixing or proportions or preparation, unless for some reason I find that that's the only thing holding me back in successful welding. Right now I'm positive there are several other factors making my welds suck :P.

Share this post


Link to post
Share on other sites

I just don't like to make negative comments about a guys product-what I was using is a true flux that people have good results with-I just didn't have the same results.

Share this post


Link to post
Share on other sites

The guy who gave the Demo last week here in Michigan that I watched had a recepie for his flux. it was 50/50 eye wash grade borax(avalible at the pharmacy) and the rest was iron fillings from a pottery store that they use for coloring pottery. from what i saw of him welding peices together it didn't take much and it worked very well.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.