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I am trying to weld some beads with a "Silicon Bronze Rod" but the result is far away from the golden bead videos that you see on youtube. The bead is covered with black oxidation and it doesnt matter how clean the metal is or how much aceton I use to wipe the rod or the metal piece. I get the same result on stainless and on regular steel. When I brush with a steelbrush the bead seems alright (see image below - I am a beginner). I have tried to use different ampere, speed, gasflow, gascups, gaslenses and you name it, I have even bought a new tigtorch if the case was that the Argon gas was, but the result is the same. I cant find anywhere on Internet that sameone has the same experience, this is my final chance to have an explanation of my horrific beads that are black of what I think is oxidation.
With proper amperage and gas coverage, it’s not hard to get good looking welds. It is also not unusual to need to shine them up after welding to remove any discoloration due to welding.
A stainless steel brush is best, gas flow should be 2x cup size, a nice large cup (#8 or better) and use a quality gas lens. Clean your material AND the filler rod before welding.
A stainless steel brush is best, gas flow should be 2x cup size, a nice large cup (#8 or better) and use a quality gas lens. Clean your material AND the filler rod before welding.
i don't think its a cleaning after its welded issue. the weld itself looks somewhat funky.
the thing with silicone bronze is your not welding, your brazing. that requires a different technique.
make sure your rods are clean, crap on the rods will get into the weld. also make sure they are tig rods not gas brazing rods.
tweak it until it breaks
It does look a little hot though.
As Tweake mentioned its brazing so you dont ever want to melt parent metal at all. I usually run 53-57 amps dc neg. Its just just enough to melt filler and get it to flow. You will still need to clean metal before. Cj mentioned wire brushing and a gentle brush brings it up nicely but if you melt the parent metal it goes grey and doesnt come back. You will know when your heat is right cause your steel will be hot enough for the silicon bronze to puddle and wet out nicely and it should dab pretty good after that, but unlike tig be prepared to go low amps ie 50 or so on even 1/8 inch + and wait till the silicon puddles not the metal. Hope you get better results mate.
As Tweake mentioned its brazing so you dont ever want to melt parent metal at all. I usually run 53-57 amps dc neg. Its just just enough to melt filler and get it to flow. You will still need to clean metal before. Cj mentioned wire brushing and a gentle brush brings it up nicely but if you melt the parent metal it goes grey and doesnt come back. You will know when your heat is right cause your steel will be hot enough for the silicon bronze to puddle and wet out nicely and it should dab pretty good after that, but unlike tig be prepared to go low amps ie 50 or so on even 1/8 inch + and wait till the silicon puddles not the metal. Hope you get better results mate.
Thank you all for tips to get this up and running.
I will try to lower the amps and see if it does any good. I think I have tried it all but I will give it another shot.
I thought it was a heat problem as well, but I have try to lower the amps and when I was on a very low amp the silicon bronze rod just "balled up" it did not melt out on the material at all.
I will try to lower the amps and see if it does any good. I think I have tried it all but I will give it another shot.
I thought it was a heat problem as well, but I have try to lower the amps and when I was on a very low amp the silicon bronze rod just "balled up" it did not melt out on the material at all.
BillE.Dee
- BillE.Dee
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Weldmonger
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Posts:
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Joined:Mon Nov 27, 2017 8:53 pm
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Location:Pennsylvania (Northeast corner)
Hi,,,looking at the picture of your work. I am thinking that there is a lot of turbulence in the pool to make it "boil" apart from the center. Try to get the material pretty warm, then work on "applying" the rod to the material without making the material bubble up. I don't know where you're located,,, Cj stated the gas flow should be 2x the cup size,,,that is cfh. you would want liters to be the same as the cup size. also, put an 8 cup on it and give it a go. Clean, clean, clean. and try not to use the same coupon, bead after bead without cooling. You will be putting a lot of heat into the coupon and then using bad words.
That was good that you stated out cfh v.s Litre, I am from Sweden so its litres per minute. BeeGee asked a question that made me wonder...he ask if my welds stays shiny after brushing, and actually they dont, not right away, but after the pice has cooled down it does. So maybe the heat is the problem after all. I will check this out and post a report here as soon as possibly. Great forum and I am greatful for the help that I get. Cheers!
UPDATE: Thanks all for the tips on how to get my silicon bronze welds shiny. I tried again now with 4mm coupon and footpedal between 10-30 Amp, the first weld was horrible, balling up on the material and no good result, it seemed to cold. But the second weld a couple of mm from the first I managed to weld with 30 amp a shiny(ish) weld, it seemed that the first weld was warming up the material and then worked and the filler rod material melted as it should. So I think that you are on the right track that my oxid welds is caused by too much heat. Mabye its a good idea to preheat the material to get the best braze result. I just cant get it how all the instructors on youtube makes it look so easy with no preparation at all, it seems they just sit down and weld a perfect weld, I have never seen a oxide braze bead on youtube...i will keep on trying, and trying I am on the right track now. Thank you all.
Its good to hear that your results are getting better.
You shouldnt need a preheat just stay in spot till the parent metal is warm enough to melt silicon bronze and you shoud be fine.
Youtube is not the most honest place to get info, I'd guess they dont show all thier mistakes and start camera after they have tuned in thier hand for the day.
All of us need or have needed practise, in my case lots, and I still tune settings for each job on scrap before welding actual job unless its a repetitive job that Ive memorised settings, and I am dubious of anyone who claims otherwise, dont even stress it.
You shouldnt need a preheat just stay in spot till the parent metal is warm enough to melt silicon bronze and you shoud be fine.
Youtube is not the most honest place to get info, I'd guess they dont show all thier mistakes and start camera after they have tuned in thier hand for the day.
All of us need or have needed practise, in my case lots, and I still tune settings for each job on scrap before welding actual job unless its a repetitive job that Ive memorised settings, and I am dubious of anyone who claims otherwise, dont even stress it.