Brazing Bronze

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So I'm going to attempt to repair a crack on a bronze statue. (hollow) and not weight bearing So please feel free to offer any advice. And here's the dumb questions to follow:The Praxair guy has a turbo torch set, says I can braze with it? In this case I thought it might be more forgiving than oxy brazing. Is brass rod the way to go? What about silver blazing rods? I have never used powered flux, is there a paste flux I can use?I have a "b" tank and regulator and an old not too hot plumbers torchI also have an oxy setupAnd can my Lincoln 140 HD run that silicon brass wire that I have seen! With 100% R-gone?Okay thanks in advance!Sent from my iPad using Tapatalk
Reply:Does it matter how it looks when it's done?It's been a while since I read the bronze chapter in my O/A book, but I do remember that it looses ALOT of strength when hot - even if it isn't really a structural area any area able to be warped by gravity should be supported to prevent that as long as it's hot. I'll try to remember reading it again later today and share any useful information I find.
Reply:Thanks, looking forward to it. I was considering using some silicon bronze wire, doing a series of spot welds, then grinding it off. Lincoln SP100 WeldpacLincoln SP 140 HD -Magnum Spool GunSent from my iPad using Tapatalk
Reply:It really depends on what alloy the sculpture is made from. If it was made in the last 40 years or so it is probably silicon bronze. If it is older, it is probably a traditional tin bronze in which case you will want to use phosphor bronze rods or wire to weld it. Try to avoid regular brass brazing rods as the color of the metal will be lighter and it will not take a patina like real bronze.Also, many older bronze alloys contain zinc and/or lead and cannot be welded with any arc process. In this case O/A is the preferred process.JohnA few weldersA lot of hammersA whole lot of C-clamps
Reply:Bluehunter40You are walking on thin ice . . .If it is true bronze - every mode you have offeredfor repair is a  no-go.Positive identification of the metal is imperative before you select the repair approach. Post some pics.Opus
Reply:Would Everdure welding wotk with it? It uses an arc gouging rod in the rod holder of stick welder and silicon bronze filler.
Reply:Originally Posted by OPUS FERROBluehunter40You are walking on thin ice . . .If it is true bronze - every mode you have offeredfor repair is a  no-go.Positive identification of the metal is imperative before you select the repair approach. Post some pics.Opus
Reply:You know, I know better than that, people say all the time "can you weld my cast iron gate" when in fact it's aluminum. Generally I tell them to take a magnet of the fridge and see if it sticks. There wrong 50% of the time. One thing I though was funny about this job is that it's a painted sculpture, why would you paint bronze after you just paid all that money for Bronze. He did say it was $5000 so I was thinking he was on track. At least at that price, it might very well be cast iron or some other junk metal. Since the metal is not exposed as its painted I'm not sure a picture would help. It does have a white corrosion around the crack, so I guess it could be aluminum? Lincoln SP100 WeldpacLincoln SP 140 HD -Magnum Spool GunSent from my iPad using Tapatalk
Reply:Lincoln SP100 WeldpacLincoln SP 140 HD -Magnum Spool GunSent from my iPad using Tapatalk
Reply:Bluehunter40Is is it painted - or patinated?Clients rarely know what they actually have;this is why they seek a metal expert.That would be you . . .  Pics will speak.Opus
Reply:Pics posted, looks like zinc based, do to white corrosion. Lincoln SP100 WeldpacLincoln SP 140 HD -Magnum Spool GunSent from my iPad using Tapatalk
Reply:Originally Posted by OPUS FERROBluehunter40Is is it painted - or patinated?Clients rarely know what they actually have;this is why they seek a metal expert.That would be you . . .  Pics will speak.Opus
Reply:It looks painted, and it doesn't look like bronze. I think you will have to look at it in person and go from there.A few weldersA lot of hammersA whole lot of C-clamps
Reply:Sounds that way. Thanks everyone for your helpLincoln SP100 WeldpacLincoln SP 140 HD -Magnum Spool GunSent from my iPad using Tapatalk
Reply:This is starting to sound like a job for household bondoLincoln SP100 WeldpacLincoln SP 140 HD -Magnum Spool GunSent from my iPad using Tapatalk
Reply:What number of rod is Bondo? Is it the same material as Who flung dung rod?
Reply:It's gonna be "special metal Bondo made for StatuesLincoln SP100 WeldpacLincoln SP 140 HD -Magnum Spool GunSent from my iPad using Tapatalk
Reply:Bluehunter40Unless 'Old-Alpo' is filled with Cocaine - tell your client to request a return of the 5-Large from the Dog Food Stable [gallery] that produced/sold this treasured art form.I would not be surprised if the same gallery didn't have a 'KalKan' edition. By phone: politely decline this project - and extend, thatif they ever have a bronze project - please contact..Opus
Reply:Opus what do you think the metal is? Lincoln SP100 WeldpacLincoln SP 140 HD -Magnum Spool GunSent from my iPad using Tapatalk
Reply:Bluehunter40From 2400 miles away - my best guess is cheap Pot Metal.http://en.wikipedia.org/wiki/Pot_metalOpus
Reply:Thanks, I already did the wiki on pot metal. Found a product called MuggyWeld super Alloy with a melting point of 350F. Still a real shot in the dark. But could be a learning experience for me as well.  Lincoln SP100 WeldpacLincoln SP 140 HD -Magnum Spool GunSent from my iPad using Tapatalk
Reply:Bluehunter40Your issue has gone - from Bronze - to Pot Metal.You and Superior Welding should directly communicate.Opus
Reply:@ Bluehunter - exposed metal has the classic appearance of zinc-centric pot metal.  Unless you really need the work, recommend you walk.  No welding required for this effort."Discovery is to see what everybody else has seen, and to think what nobody else has thought" - Albert Szent-Gyorgyi
Reply:Originally Posted by G-sonDoes it matter how it looks when it's done?It's been a while since I read the bronze chapter in my O/A book, but I do remember that it looses ALOT of strength when hot - even if it isn't really a structural area any area able to be warped by gravity should be supported to prevent that as long as it's hot. I'll try to remember reading it again later today and share any useful information I find.
Reply:What I have learned several times is when I think a job would be a good learning experience, sometimes all that is learned was not to take those kind of jobs. Till the next time............All you can expect to gain from this experience is bad publicity.....Don't walk away RUN....Measure with a micrometre, mark with chalk,  cut with a torch.Never force anything...just get a bigger hammer.RoyOld Airco buzz box approx 1974Lincoln mig pack 15Lincoln 175 square wave1954 9" south bend lathe
Reply:Well thank you all. He was pretty let down when I told him it was pot metal and not bronze. In the end I passed on the job, told him I didn't see the repair going well. I explained that the only option I had was that muggy weld stuff and I thought it seemed questionable at best. Again thanks for the feedback and education guys. Lincoln SP100 WeldpacLincoln SP 140 HD -Magnum Spool GunSent from my iPad using Tapatalk
Reply:That's probably for the best.  The other option is JB-Braze.
Reply:Aladdin 3 in 1 rod can work on pot metal.
Reply:Okay guys, just when I thought I was done with this job, the guy calls me today and says he was sanding down the cracked area and the the metal is gold or brass colored. Does that open up the possibility that it's brass or bronze? I'd like to just drive down and do the dam job. Lincoln SP100 WeldpacLincoln SP 140 HD -Magnum Spool GunSent from my iPad using Tapatalk
Reply:Bluehunter40Your project is like a cheap piece of meat - 'the more you chew it' - the bigger it gets.It's time: for research reading . . . What is [real/casting] bronze . . .http://en.wikipedia.org/wiki/Bronze_sculptureWhat do you have . . .http://www.nationalbronze.com/pdfs/spec_reference.pdfCan I weld it . . .http://www.copper.org/publications/p.../pdf/a1050.pdfor, do I braze it . . .http://www.brazing.com/techguide/pro...er_welding.aspThe white incrustation are indicative of a high zinc/lead alloy - which points to brass.Brass is joined via soldier/brazing - and not welded.Opusps If this was my piece I would strip the paint, and let nature take it course - for honesty & arts' sake?Any repair is akin to welding on a rusted-out muffler,it will only reveal - another [larger] problem.