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I have a piece of cast iron that needs to be welded. It is a leg from one of those 50's patio sets. Every welding shop in town says "yeah, no problem I can weld that" but when I ask about the process they will use or how much experience they have welding cast iron they just want to say "it's easy". I want this done right. How should I vet a welder so I know it is going to be done right? Of course the right way seems to be subjective to who you ask. How about sending it off to someone? I see http://www.locknstitch.com/castironwelding.htm and they seem to know what they are talking about but do they? Attached Images
Reply:I think, and don't quote me, when you weld the steel, it has to be heated up before hand, and slowly cooled with sand.
Reply:I think bronze brazing it with oxy/acetylene would be the way to go to fix that. And if it was repainted after fixing I think it could do it so that you wouldn't really be able to see the repair. While I don't think there's any thing all that "hard" about doing it, I can for see it taking an hour (or a little more) to do it. So the big question I'd have for you would be is it economically worth it to you to get it fixed?
Reply:Originally Posted by 4956I think bronze brazing it with oxy/acetylene would be the way to go to fix that. And if it was repainted after fixing I think it could do it so that you wouldn't really be able to see the repair. While I don't think there's any thing all that "hard" about doing it, I can for see it taking an hour (or a little more) to do it. So the big question I'd have for you would be is it economically worth it to you to get it fixed?
Reply:You won't be paying much for the weld (or brazing). You'll be paying for the skill set that will having you walk away with one piece instead of twenty.Yes, cast needs to be pre-heated, small, short welds and cooled slowly. It's not hard. And doesn't take a whole lot of active time. Maybe 1-2 hours of oven pre-heat, 20 minutes prep and weld time then 4 hours controlled cool down.Be wary of The Numbers: Figures don't lie,. but liars can figure.Welders:2008 Lincoln 140 GMAW&FCAW2012 HF 165 'toy' GTAW&SMAW1970's Cobbled together O/A
Reply:Originally Posted by mike837goYou won't be paying much for the weld (or brazing). You'll be paying for the skill set that will having you walk away with one piece instead of twenty.Yes, cast needs to be pre-heated, small, short welds and cooled slowly. It's not hard. And doesn't take a whole lot of active time. Maybe 1-2 hours of oven pre-heat, 20 minutes prep and weld time then 4 hours controlled cool down.
Reply:How much weight is this leg going to support?GravelThe difference between theory and practice is that in theory there is no difference.
Reply:A chair and body. A couple hundred pounds will be in the seat at times so 75 lbs maybe.....there are 4 legs and this is a rear leg.
Reply:Search for some of CASTWELD's post on the forum. Peter is a true master of cast repair. His posts will walk you through the prep and process. You could always send it to him for repair.RogerOld, Tired, and GRUMPYSalesman will call, Batteries not included, Assembly is required, and FREE ADVICE IS WORTH EXACTLY WHAT YOU PAY FOR IT!Dial Arc 250HFThunderbolt 225 AC/DCAssorted A/O torches
Reply:Ronnie,Most of the stuff I do where I work gets billed out at $65 / hour. So I think you should expect to pay some where in the 65 to 100 range for a decent job. Do you have an oxy/acetylene set up and a die grinder? Because if you do I think you should try and fix it your self. I'm willing to consult on the project. If we're successful you can FedEx me a bottle of Pendelton as compensation.
Reply:Originally Posted by RonGA chair and body. A couple hundred pounds will be in the seat at times so 75 lbs maybe.....there are 4 legs and this is a rear leg.
Reply:Take it to the busy shop, should be a good indicator of a shop that does good work.Sent from my SCH-I200 using TapatalkYeah, I know, but it'll be ok!Lincoln Square wave 255Miller Vintage mig30a spoolgunThermal Dynamics Pacmaster 100xl plasmaSmith mc torchEllis 1600 band saw
Reply:Originally Posted by GravelI wouldn't braze it then. I would either follow proper procedure or take it to a pro. Just my opinion...
Reply:I agree that it should be brazed.
Reply:Originally Posted by GravelI wouldn't braze it then. I would either follow proper procedure or take it to a pro. Just my opinion...
Reply:Is it going to be as strong brazed as welded?Actually, though high nickel would be a stronger repair, brazing should hold up a chair for many more years. Plus, it is easier to do.Last edited by Gravel; 05-13-2014 at 08:34 PM.GravelThe difference between theory and practice is that in theory there is no difference.
Reply:Originally Posted by Rog02Search for some of CASTWELD's post on the forum. Peter is a true master of cast repair. His posts will walk you through the prep and process. You could always send it to him for repair.
Reply:Nickel rod can do the trick nicely and quickly if you know what your doing. all cast is different. Almost feels like the luck of the draw some days. I do cast repairs on pot belly stoves and furniture for a guy all the time. He restores them and sells them. 8 out of 10 times i use nickel rod DCEP no preheat and never look back. Sometimes its a bad dream that turns into a nightmare. Like I said cast is a temperamental little bugger. The rod takes some getting used to and is not cheap. Good luckNick
Reply:Brazing or high nickel rod would work. I do lots of patio furniture for the local powder coater and much of it is cast. Fastest would be high nickel rod. I would do it just like TMW said and do it all the time. Just don't ever do more than an inch at a time and peen between welding and you will have no problems.
Reply:http://www.lincolnelectric.com/en-us...ncolnElectric)Lincoln Ferrowelds work great.PrepThrow in gas grill WeldThrow back in grill turn it off allow to cool.PaintLincoln Electric:Ranger GXT 250SA-200LN-25Pro MiG 256Pro Mig 180Esab CV 251Invertec 160Victor Torches
Reply:Originally Posted by Excaliburhttp://www.lincolnelectric.com/en-us...ncolnElectric)Lincoln Ferrowelds work great.PrepThrow in gas grill WeldThrow back in grill turn it off allow to cool.Paint
Reply:Ronnie,Sweet danc'n Jesus on a whole wheat cracker man, do not let some one talk you in to an arc welding attempt at repairing this.
Reply:Stick weld with Ni rods, or MIG with crown alloys wire, braze would likely hold just fine as well. 70s-6 may even work depending on what it was really cast out of.
Reply:First thing I'd do is sand blast all the paint off both pieces so I didn't have to breath any burning paint fumes while I was working on it. Most likely it's grey cast iron. I'd use Low Fuming Bronze rod (Harris 15 flux coated would be a good choice). It wets out and flows good around 1700 F. (orange). You get it much past 1750 F. and you'll start boiling some of the lighter elements out of it (like the zinc, tin and lead). You can tell when you're getting it to hot by the way the puddle reacts (boils) and the porosity you'll start getting. Use a neutral flame. Only prep one side of both parts (about half to 3/4 of the thickness) at first so you have some of the original broke edge left to help you get the parts lined up correctly. I'm assuming you've got a clean break between two pieces with no extra little bits between them. Do not use a grinding rock to make your prep. Grinding leaves smeared carbon platelets on the faying surfaces that will interfere with the bronze forming a good solid state bond with the parent metal. A carbide burr in a die grinder works best. A file will leave you a good clean surface also. I can't over emphasize the importance of this. I understand your reluctance to attempt this with out ever having done it before. So what you do to develop your skills and gain some confidence is get a piece of 2 x 1/4" hot rolled flat bar and cut it up into 2 " pieces and start running some practice joints. I'm pretty confident you should be able to learn to do this with a little bit of practice. You can put your practice pieces in a vice and take a hammer to them to see how good a bond your getting.
Reply:I guess I should have told you that after you get the first side off it brazed you flip it over and use your carbide burr to cut a groove down into the part on that side so that you end up with a full thickness bond.Originally Posted by GravelIs it going to be as strong brazed as welded?
Reply:http://www.harrisproductsgroup.com/e...nze-15-FC.aspx
Reply:Originally Posted by G-son that the brass has lower tensile strength than mild steel.
Reply:No votes for JB Weld?
Reply:Originally Posted by 76GMC1500Brazing is NOT done with brass. It is done with silicon bronze which is quite a bit stronger than brass. Silicon bronze has a yield strength of around 60ksi which matches the strength of a 6011 welding rod and far exceeds the strength of mild steel between 40 and 45 ksi. Brass is typically 20ksi. Cast iron is typically 30-35ksi.
Reply:Originally Posted by 4956Really??? Since the two main elements that make up brazing rod are copper (around 60%) and zinc (25 to 30 %) with only 0.15% silicon and around 1% tin I think technically it's more of a brass than a bronze. I think you may have "brazing rod" confused with Silicon Bronze tig and mig wire. Those usually have a max of 1% zinc. "Brazing" rod and Silicon Bronze tig rod are two different critters and they're not inter changeable.
Reply:Originally Posted by 4956Ronnie,Sweet danc'n Jesus on a whole wheat cracker man, do not let some one talk you in to an arc welding attempt at repairing this.
Reply:It's just sad that brazing is a lost art yet so perfect for this case. And it just looks cool because you have that gold filler to highlight the "yeah I did that" when you are sitting around drinking beer and showing it off to your buddies.
Reply:Brazing is ideal in so many cases but simply looked over. Here is an example of brazing a pipe bung into a small flange. It's done with 50N which is expensive but it saves my a bunch of time finishing this thing in the lathe because there is almost no distortion. I simply drew it clean with a file. And it's hell of strong with a tensile strength of 110 ksi and full penetration to the back side of the joint. And with having the bolt holes so close there is almost no bead to have to grind away for bolt clearance. It did not need to be any of this as its simply a lube drain from a turbocharger but whatever... I didn't pay for the material and I like the experience.Last edited by 76GMC1500; 05-14-2014 at 11:44 PM.
Reply:Originally Posted by 76GMC1500Aluminum and tin are what make bronze what it is. They are there in very low composition. Bronze is nothing like brass. It is much stronger. It is not subject to de-zincification. It is weldable (brass is not). Nickel adds corrosion resistance and iron adds strength. That is why my propellers are made of NiBrAlFe. Thats nickel aluminum bronze with an iron addition. Brass is simply copper and zinc. Get some brass wire and try brazing with it. See what happens. Try forming a spring out of brass. Try leaving brass in salt water. I mean while they may share some alloying elements brass and bronze are not the same thing. You can braze with silicon bronze and that is what most "low fume" bronze rods are. Brass does not tolerate brazing temperatures because the zinc tends to start off-gassing before the brazing temperature is reached causing porosity and poor fusion. Brass is broken down into yellow brass and red brass compositions. Red brass has much less zinc and is closer to bronze in terms of corrosion resistance. But it still does not have the aluminum/tin addition that makes bronze what it is.
Reply:Originally Posted by 76GMC1500It's just sad that brazing is a lost art yet so perfect for this case. And it just looks cool because you have that gold filler to highlight the "yeah I did that" when you are sitting around drinking beer and showing it off to your buddies.
Reply:Originally Posted by Excaliburhttp://www.shopfloortalk.com/forums/...ad.php?t=13653To each his own. Either process will get the job done.
Reply:Originally Posted by slagdNo votes for JB Weld?
Reply:Originally Posted by 4956First thing I'd do is sand blast all the paint off both pieces so I didn't have to breath any burning paint fumes while I was working on it. Most likely it's grey cast iron. I'd use Low Fuming Bronze rod (Harris 15 flux coated would be a good choice). It wets out and flows good around 1700 F. (orange). You get it much past 1750 F. and you'll start boiling some of the lighter elements out of it (like the zinc, tin and lead). You can tell when you're getting it to hot by the way the puddle reacts (boils) and the porosity you'll start getting. Use a neutral flame. Only prep one side of both parts (about half to 3/4 of the thickness) at first so you have some of the original broke edge left to help you get the parts lined up correctly. I'm assuming you've got a clean break between two pieces with no extra little bits between them. Do not use a grinding rock to make your prep. Grinding leaves smeared carbon platelets on the faying surfaces that will interfere with the bronze forming a good solid state bond with the parent metal. A carbide burr in a die grinder works best. A file will leave you a good clean surface also. I can't over emphasize the importance of this. I understand your reluctance to attempt this with out ever having done it before. So what you do to develop your skills and gain some confidence is get a piece of 2 x 1/4" hot rolled flat bar and cut it up into 2 " pieces and start running some practice joints. I'm pretty confident you should be able to learn to do this with a little bit of practice. You can put your practice pieces in a vice and take a hammer to them to see how good a bond your getting.
Reply:Originally Posted by 76GMC1500Aluminum and tin are what make bronze what it is. They are there in very low composition. Bronze is nothing like brass. It is much stronger. It is not subject to de-zincification. It is weldable (brass is not). Nickel adds corrosion resistance and iron adds strength. That is why my propellers are made of NiBrAlFe. Thats nickel aluminum bronze with an iron addition. Brass is simply copper and zinc. Get some brass wire and try brazing with it. See what happens. Try forming a spring out of brass. Try leaving brass in salt water. I mean while they may share some alloying elements brass and bronze are not the same thing. You can braze with silicon bronze and that is what most "low fume" bronze rods are. Brass does not tolerate brazing temperatures because the zinc tends to start off-gassing before the brazing temperature is reached causing porosity and poor fusion. Brass is broken down into yellow brass and red brass compositions. Red brass has much less zinc and is closer to bronze in terms of corrosion resistance. But it still does not have the aluminum/tin addition that makes bronze what it is.
Reply:The term "brass" is just so generic that it causes a lot of confusion when it comes to talking about joining (or working with) copper based alloys.To help illustrate just how many different kinds of these copper based alloys can get called "brass" check this Wiki article. Part way down the page there's a list of different ones, what they're used for and their nominal compositions. http://en.wikipedia.org/wiki/Brass
Reply:Also there's an important difference between "brazing" and "braze welding"."Brazing" is where the filler metal gets pulled into the joint by capillary action and requires a temperature above 840 F. Such as the case with that pipe bung getting "brazed" into the flange with 50N pictured above. If the filler metal melts at a temperature below 840 F. technically it's know as "soldering". An example of that is what plumbers do with copper water pipe and fittings.What I've been talking about for making this cast iron repair is "braze welding". It does not depend on any capillary action to get filler metal into the joint but is deposited as beads in grooves or fillet weld configurations similar to that used with regular arc welding. The big difference being is that it's done at a temperature below the melting point of the parent metal.
Reply:is the nickle powder method still used today? is this a preferred method?
Reply:This is in no way a recommendation, But back in 2002 or so, i was fixing a loader bucket on a building site and one of the electricians brought a broken chinese vise head to me and begged me to fix it so he could keep working.It was one of the ones with the swivel head and some really grainy ugly cast iron. Told him I didnt have time to do it "right" and it probably wouldnt hold anyway, but he was persistent. I had been using .045 NR 211 on the bucket, to prove it would NOT work I just bevel it and put 3 nice hot passes around it. No preheat, no peening, and really no care. Dang... the thing held together. Go figure.
Reply:I think the reason that worked out is because the vice head was most probably cast steel and not cast iron.
Reply:Originally Posted by welding_kidis the nickle powder method still used today? is this a preferred method?
Reply:Originally Posted by 4956I think the reason that worked out is because the vice head was most probably cast steel and not cast iron. |
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发表于 2021-8-31 22:30:28