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I Forge Iron

If at first you fail your deed....

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  Hello,everybody .The California evening had cooled enough here that I couldn't resist heading out to the forge. I had no specific project in the works,so I decided to experiment with forge welding,particularly what I've heard referred to as a "jump weld" (see attached photo). I wanted to try and weld a 1/4" piece of square stock to a larger 3/4" square stock,using a jump weld.


 Things didn't go so well.


  I cleaned up the stock with 80 grit on the belt sander,rounded the end of the smaller piece,and created an indention to fit the rounded portion on the surface of the larger stock. (yes,I should have taken some pictures)  Making sure the pieces were totally clean,I set them aside while the forge preheated. I was using a propane NC forge (two burner) ,with the psi set at 15. My anvil was cold,so I heated a scrap piece of plate up to orange heat,and set it on the anvil for a while to warm my welding surface.


  Once the forge was up to temperature,I put the 3/4" piece in,waiting until later to insert the smaller one to avoid burning it while waiting for the large stock to come up to temp. I fluxed both with borax at bright red heat,almost orange .


 That's when things started getting strange <_<


 Although the flux melted initially, it started to form a strange black substance on the surface of the steel,instead of bubbling and behaving like flux should. The longer i left it in,the worse it became

Soon the whole surface had become contaminated.Needless to say,the weld didn't take  ( I don't know why I even bothered to try at that point ) I cooled the steel in water and examined it.. a black,glossy,almost glass-like substance coated parts of the steel,which I assume to be my flux gone wrong. There was also heavy scaling,which looked more metallic than what I'm used to seeing. I tried the weld twice,with the same results. Instead of frustrating myself further,I figured I'd seek some exterior knowledge .


 So,are there any ideas on the issue?Has anyone experienced the same thing? Is there too much oxygen in my forge? Did I burn something? Is there something wrong with my flux?I'd love to hear what all of you experienced peoples have to share :)


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When you work outside in day time the steel may be hotter than you think. And when you let color show before you flux you already are building scale on the metal you cleaned. I flux at the lowest heat that the flux will stick...When flux discolors like you described it is most likely burnt. Have to start over and reclean. Wot you described is not a good place to start learning on. Like above, faggot welds,,,then more of them then more etc.Remember to tap lightly first few heats,,,if you are showering shop with sparks you are hitting too hard.


Forge welding is one of those things that once you do it well you will wonder how it ever seemed difficult at all.

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Thanks for the replies, gentlemen. It's not that I hadn't forge welded before,it was the specific weld/situation that was giving me issues. After a bit of tinkering,I do believe that my burners may have been running too hot,or at too high of a psi,which was causing my flux to burn,as well as the steel. I adjusted accordingly,and although I haven't attempted the same weld again,I've been working on a wrought iron/ 1060 billet ,which welded with no issues (see attached photo).  So in a way,Mr Hale,you were indeed correct...the steel was hotter than I thought. Appreciate the input,guys


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