Yes, if you're a welder doing a range of jobs and on different materials, you'll become a little bit of a metallurgist automatically! Something of a mechanical engineer, too: The holes you drill to stop cracks accomplish that by spreading out stresses around the edge of the hole (instead of the tiny area at the point of the crack), reducing the stress concentrations that drive crack propagation. I like the explanation and the explainer. Would it have reduced crack risk in this repair if the block was modestly preheated and then covered with a blanket after welding?
Sir, your oral presentation is wonderful. The way you speak, no 'filler words', the confidence in the information. No dumb music. Thank you for letting me visit! Bill
Ive watched a LOT of welding instructional videos in my time. Most of them, the instructor blathers on about nebulous BS and you have to suffer through the nonsense to get to heart of the matter and even then they do a poor job actually being a teacher. This is, by far, the best instructional video (well, its up there with Jody's stuff) Ive watched. Not one second of this is wasted time watching, and every point made by this guy is on-point with this logic, metallurgy and materials-science conclusions. Well done sir.
I've been repair welding for 50+ years. I thoroughly enjoyed how you conveyed the information. Aluminum bronze is also my go to. The only thing I do differently is that I take a once over "cleaning pass" without any filler. I use lower amps, lower frequency, high reverse polarity to help pull impurities from the weld area prior to setting up for the actual brazing. I rebrush and acetone the entire area. Then I lower the dcep, slightly raise the ac frequency and start the brazing. My effort going over the area first with lower heat and higher dcep seems to result in less impurities floating out of the braze during the actual brazing of the crack.
Straight up info! Been doing this since I was 16 in 76'... with twisted wire brazing with a jeweler's torch. My uncle ran a Pressure Vessel shop and taught me how to do X- ray repairs guys twice my age mainly tried... lol. Adapted from Eutectic filler to solid rods we center less ground, to Aluminum Nickel Bronze with proper 2 step preheat and gas adjusted by a progressive/regression type monitoring. Our contracts teaching D.O.D. personnel has been a stellar advancement for " OUR BOYS ". KUDO'S my friend... you are on point. Seth
Back in 87 at the community college to tie up our AWS cert & diploma we were required to do 80 hrs of community projects, labor was free, only charge on material if needed. Cost was a can of coffee, & a baker dozen from Dunkin donuts. Every thing from hard facing on dozer blades, rippers, rebuilding roller pins machine shop there would turn down, rewelding bicycles frames, rebuilding anything & everything... But this little Hispanic lady came in with a tortilla pan thats been in her family for four generations, had a hair line crack in the center, took for ever to get that carbon out of it.. but I did, ran two pilot holes to stop the crack, preheated, post heated, stress relieve, I forgot what rod we used, but it was very similar to hi Nickeli chromium base.. came out great, but when it came to getting the coffee& donuts, this lady brought in a complete home cook mexican meals for the entire shop.. Enchiladas Burritos, tacos refried beans, homemade salsa, fresh salad it was unbelievable what this lady & family did... 😊
If I may I'd like to share previous experience with cast iron weld repair. Certified 20+ years as aerospace welder/shop supervisor in the structures and powerplants depts and race car fabrication. As you have learned, being a welder means sometimes you are everyone's 'best friend'... Running these depts I had a heat treating oven available for pre and post weld heating and cool down. Years ago, a cracked set of SB Ford heads were cracked. The 'old school' method suggested brazing with silicon bronze filler. Descale the area, stop drill the cracks, v-gouge the cracks, pre heat soak to 300+ deg. AC tig braze fill from both ends of cracks towards the middle with good overlap then slowly cool in the ovens. At about 6 hours with heads cooling near ambient temp, heard the awful sound of cracking!!! Repeat the process, eventually saved the heads. A lot of time, effort for a maybe repair. There has to be a better way. Talking with a Eutectic sales rep, he suggested I try their special rod intended for cast iron and mismatched ferrous alloys, the Eutectic 680 filler. Available in tig and stick form. Intended as a specialty filler for difficult, unusual weld repairs. It has the unique ability to tenaciously hold onto the base metal but.. the filler puddle will 'relax' as it cools preventing post repair stress cracking. A somewhat low temp filler similar to your alum/bronze filler. A friend racing a seriously modified Austin Healey Sprite in autocross his engine was in need of rebuild at a storied foreign engine machine shop. There you might find anything from a Fiat to a Ferrari engine overhauled, balanced and blueprinted. They magnafluxed the head, found it cracked between cyls 2-3. Very common... two siamesed exh. valves side by side with no cooling passage between them and they both share one common exhaust port. A disastrous design doomed to failure. The machine shop owner said 60% or more of the BMC 850,948,1100 and 1275cc series heads all share this trait, showed me a stack of cracked heads with this, all deemed unrepairable and that good useable heads were becoming very scarce. Decided to give the Eutectic filler a try. Carefully v-gouged the crack until it seemed to end, close to 5/8ths inch deep. Heat the area with a torch, inspect with magnifying glass to ensure the end of crack is found. AC tig/braze with the filler, not worried about excess build up. The machine shop will take care of that. Head returned to machine shop, passed magnaflux test, shop milled and ground repair area, installed hard exhaust seats, repair deemed successful. I did 6 more of these heads for the machine shop at $100 each, all successfully repaired. A Harley owner with old cracked knuckle heads came in that had been very poorly repaired at a high cost asked if I would try to fix his heads. Not a Harley fan, didn't give the loving care I had the others I found some of the nastiest, dirtiest cast iron ever encountered. Pockets of sand, oil that would explode while welding, grind back, try it again. Like it or not, the repairs worked. To this day I consider the Eutectic 680 a 'wonder rod', seems able to hang onto, weld virtually anything of a ferrous base metal. Maybe this could be also added to your arsenal of repair fillers for difficult situations. YMMV...
Nice video and explanation! Not long ago I TIG welded a cast iron exhaust manifold for a Kohler engine. I used stick cast iron rod (Ni rod) and cleaned off the coating. Pre heated the part to about 350 degs. Like you I jumped around the part to minimize stressing. I than heated the part again and put in in sand to slow cool it. I was surprised how well is welded except for a few pops due to carbon or voids.
Great process Cliff, I tried cast iron repair for a short time back in the early 90's while doing cracked cylinder head repair (mostly aluminum) at a machine shop I worked at. I bought cast iron rods our supplier suggested, and went to town with rose bud pre and during weld, sand to cover while cooling. Many tries, no joy. I almost bought a used pizza oven and then decided to keep brazing when possible and use an old method of drill and peen plugs in combustion chamber with success. Thanks for sharing your processes with me. Really challenging work. Happy to see people like you willing and able to save the old iron. Great job, Thank you.
👍Brazing is always the correct answer when it comes to cast iron repairs.. I've always used regular silicon bronze filler but I will have to try aluminum bronze next time.
I like his reasoning about Using Aluminium Bronze because you run it on AC, and the AC action helps to clean out the crap from the weld area. Great Video.
Usually cast iron welding tutorials are all about pre-heat and post-heat and burying it in sand. I've never used TIG I just have some rain gutter to repair, this looks like the way to go. The rod isn't cheap but fixing cast iron is a valuable skill.
I agree, this video had very helpful details as to "why" cast iron is handled differently, too many generalizations are not useful in actual practice, details matter.
technically it's not a weld it's bronze brazing but that's still sometimes useful and water jackets-outside aren't stressed as much typically i got a 426 hemi iron 1970 block that needs repairing/mod's and was hoping to avoid using gas-welding as it's not my favourite to use
@@tgreening the goal when doing it is to have the welder getting to all of it and on the end's about 1/8 more so the crack's don't have a easy placement to start again as far as over grinding yes technically possible but it just makes more time/work to fixing it but not enough and you probably will have to grind out the hole old weld you just did as it probably will crack the weld or close to it
Great job on the repair. Aluminum Bronze on cast is technically a low temperature braze as opposed to a "weld", which is usually the term used for a "Fusion welding". Now I can let gramma police take the rest of the day off. I was a professional welder (in another life). While I rarely had to weld any cast iron, I once had a situation where a large knuckle dragging pipe fitter, overtightened a cast flange that was NPT, meant to get threaded onto some galvanized pipe for an emergency shower system in a petro-chem plant and cracked it. The shutdown was over and the owner wanted the plant started up, but it would be weeks to get another flange (local suppliers don't stock cast #150 NPT flanges). There was some discussion about MacGyver-ing something up (the system only holds 100 psi warm water), but I said "Why don't we try silver solder on the crack and see if will hold?" With nothing really to loose, they said to give it a try and wait for it.........the repair worked find and for all I know it is still operating. The moral of story is, all repairs on cast iron are unique and what works in one situation may not be appropriate for another. If the joint I fixed was subjected to high heat or thermal cycling, the silver solder may on have worked.
A tip I learned is to not use grinder disks/flap disks on the cracks to be welded. The disks, apparently, create a gouge where the ground carbon fills the porous cast. This causes more carbon to migrate into welds. The tip I learned was to use carbide burrs to CUT out the crack, instead of grinding.
Just filled a small hole on some core shift that appeared during a gasket match on a SBC head. Did the standard 400* preheat with a slightly carburizing flame with a postheat, then insulated the structure for a slow return to room temperature. Hopefully to keep some ductility in the repair and eliminate the possibility of a crack. Used a 3/32" Nassau Brutus A electrode designed for spring, tool, and casted steel for the 1/2" repair area. Your video was great and very informative and reminded me of my college Metallurgy course with an emphasis on practical application. I will definitely try the aluminum bronze on a large structure repair next time where ductility is needed due to expansion and contraction during the heat cycling of things like an engine block. The use of a lower melting point filler material like aluminum bronze will be an advantage and minimize the heat affected zone of the repair. Great video and the knowledge shared was equally great!
From UK. That was a brilliant comprehensive technical overview of the process. Clearly put and Thank You so much for speaking to us in such a well paced way. Great job. I once worked in BTH, English Electric Steam Turbine Div. Willans Works, at Rugby town central England. The main product there was Prime Generator Turbines for public utility power companies. The large castings for steam chests weighed many tons and were produced in sand boxes in their own foundry. I reckon these weighed dozens of tons and like you say about residual stresses - they would crack on cooling. Multi million dollar item! The firm had welders based in the foundry ready to fix things. They used Bronze Welding (called Brazing in UK) and after QC X-Rays (& dye penetrant testing if I remember right) temporary gas fired oven (portable shields) were put round these monsters and specialist technicians in aluminised fire suits with I think water cooling etc would run the liquid gold magic silicon bronze into the prepared cracks. Yes the had ovens big enough to take the covers of a low pressure housing off a 600 Mw set. Preheat and bronze weld. The firm is now part of General Electric I hear and there must be others out there who know that factory of the process and can correct me where I'm wrong on any details. Keep the videos coming. You all got own styles and all of you are highly educational. Thanks!!
Thank you for being articulate and knowledgeable on metallurgy It seems welders now a days are getting more and more scientific and knowledgeable and it’s great.
Fantastic video, great explanation on the metallurgy of cast it’s always been something I’ve stayed away from welding. The Ol boys always Said “If you can’t cold stitch it, Scrap it” thank you for sharing 💪🔥🔥🔥
I didn't get anywhere near this level of detailed information when I took a welding class years ago. He would make a great instructor at a college or vocational school.
Thank you for a very informative video, very practical and down to earth and honest. What a genuine fellow, really cares about getting the practical info across and teaching the audience. Thanks again.
Just got done using this to fix my brand new $2000 block.. worked like a charm.. thanks for posting this! Welded very easy and clean as well.. it was on a part that broke off that holds a M8 head bolt at the top.. already machined and tapped and tq held way passed what is needed of it!
I learned a lot from this video , I had no idea there is so many different types of cast iron . I do know cast iron is extremely hard to successfully weld . Awesome video . TO BE TRUTHFUL I WAS EXPECTING TO HEAR THE BLOCK CRACK AS YOU WERE FINISHING YOUR VIDEO .
Non welding person at all here. Best video I have seen so far and I have seen many. To say the least/most (🤔🤔🤔🤔, both a compliment) all I learned from this is that I will not be TRYING to repair my brothers block. It's the bolt hole for the starter, it has two cracks. So we were thinking HEY JUST USE A MIG WELDER AND TACK IT AND EVERYTHING WILL BE FINE. IT WILL PREVENT THE CRACK FROM SPREADING AND HOLD THE STATER IN PLACE, but no.
WOW, someone that understands metallurgical terminology but have never heard of using aluminum as a filling metal for a ferrous metal repair. I've been an aeronautical and heavy equipment welder for over 30 years (17 years as a certified Naval Aviation and shipboard welder) and have repaired numerous cast products but the use of aluminum is definitely different. 90% of the time I used a Nickel base filler metal whether (GTAW & SMAW) but always used a rose bud to pre-heat and post-heat after each welding process. But I will definitely look into using an aluminum base filler rod. Thanks for sharing your findings.
All Great advice. I often use Silicon Bronze for cast repair but I'm almost never repairing engine blocks. Mainly manifold and such where it needs to be sealed but not structural.
Aluminum bronze is supposed to be stronger and harder. I've heard more elongation too, but not sure of that. Using AC (instead of DC that's typical for silicon bronze) should provide some cleaning action that will help cope with the impurities you'll face in old cast iron. Should only need relatively small cleaning action, maybe 10% EP vs the typical 25-30% that would be used for regular aluminum. BTW, I like the encouraging tone of this guy!
Best discussion about cast iron's carbon content and weld repair characteristics that I've heard. I tend to think bronze brazing due to elongation and ductility. I like the aspect of lower temperatue and its wetting actionwhich makes me 'feel' like it's really joining with the cast surface. No issues with repairs with bronze rod yet.
Great presentation. You seem to know what your talking about. I would like to see you do a video on the same subject using nickle alloy rod. Thanks man!
Can't wait to try aluminum bronze. I have tig weld with muggy 77 with good repairs. Welding cast aluminum is the same , great prep=a nice solid repair with no come backs .👍
Will definitely have to try this. Welding cast for me can sometimes be easy and go great. Sometimes extremely difficult. Definitely a steep and quick learning curve. But i haven't had any failed parts yet. Only failed attempts that i had to come at in different ways to complete.
The best results i have had welding cast has been with a stick welder using "Arctec #3" i have done brazing and acetylene welding cast iron, i have yet to try Tig welding cast, next time i will, thanks.
Great video, lots of info on the metallurgical part of welding. On side note, I had to weld a crack in punch press arm some time ago for the company i work for. We didn't had any ac capable welding machine just mig and a little dc tig welder, i chose to use the dc tig with 316 stainless as filler(of a mig reel lol) and its been fine for the past 3 months.
The difference between grey cast iron and nodular, or malleable, cast iron is the heat treatment performed. The carbon contents of both types are in the same range. The problem with welding cast irons is avoiding fast cooling rates that allow the formation of "white" iron which is basically Iron carbide or cementite. The when iron gets above a certain temperature there is a change in structure and the carbon goes into solid solution. If this structure cools too quickly, then a form called martensite forms which is very brittle. The key is to preheat the cast iron piece, perform the welding, then cool slowly. The area that he is referring to in the weld is called the heat affected zone or the HAZ. Rather than welding, an alternative process is to braze the crack. Also at the tips of the crack is to drill them out and insert a threaded plug. Nice job.
Excellent tutorial! I wish you were in Idaho. I have a 1938 Waterous pump housing, for a 1938 Ford Luverned fire truck, that froze and cracked at some point in its 84 year life. Someone tried to weld it and it appears to be herendously awful. I am not even close to having the skill to weld it but I wanted to educate myself as I look for someone to weld it.
You gave me a lot to think about in this one. I am just getting ready to ramp up repair on a large Athol vice with a broken 1" thick mount ear. Clearly, this is going to be outside my wheelhouse. Have any advice?
Great explanation!! I also have done many cast weld repairs including cast aluminum( which is a freaking nightmare) you were dead on in your description and methods.....I'm very glad you did such an in depth explanation...my only suggestion would be to go into a little more detail on the cleaning and grinding procedure. Great job!
I loved learning metallurgy. Just remember....brittle means cracking. Cast iron in general does not like going back into a molten state. I've thrown blocks into a home stove before because like he's stated, the best way is heating the medium. It's more difficult heating cast iron because you have a hot block or cylinder head's in my case but, it's worth it. At least from what I've seen and done.
No pree heat or post heat? I also use a needle scaler to blend in after final grinding, making it look like original casting. When painted you can't tell the difference. Good job 👍
I’m not a welder, have never welded, but have always had an interest in it. So now by utube I’m learning a lot about. I watch your site as well as others and hope to someday get a chance to lay down a bead. Not professionally but just to build my skill base.
Teach yourself to fusion weld with oxygen/acetylene and the rest of the welding methods and materials will come to you naturally, oxy/acetylene (gas or flame welding) is overlooked as an outdated method of welding when in reality it is very effective, strong and versatile, to this day I still use gas welding often because it makes some jobs easier to perform than one of the modern welding methods.
Carbon does not harden steel because carbon is hard in itself, carbon hardens steels because it interrupts the crystal structure. This can be thought of almost like how they add gravel and other aggregate to concrete to increase it's strength (Though they also add gravel as it reduces the amount of concrete needed by adding filler). Y'all always put out really great videos though, glad you make them as I am teaching a friend to weld as of now and have been using your videos to help cross reference my own knowledge from when I learned to weld. 2:48 Edit: Also carbon is only hard when in certain forms, things like graphite are quite soft while diamond or graphene are quite hard. Ceramics containing carbon are also generally very hard like the many types of carbide in the shop. Generally the carbon we encounter in our daily lives can be thought of as soft though.
Higher carbon content Does make steel harder. Haven't you ever heard of high carbon steel? Just drill a hole in it compared to drilling in mild steel, you'll see.
Dad was a farmer from Idaho he brazing rod and the torch not to much at once. I like alum bronz tech.. I've seen a needle gun used to hide repairs on cast end to pean for stress relief. 😩
Very interesting. I have welded cast iron using high nickel content stick rods, with pre and post heat and peening in-between the short weld beads l laid. The repairs have been a successful. I will try some of those rods if l can get them in the UK? Too stuff.
Thanks for the great tutorial. I am planning on repairing my Chevy 350 block that froze a few years back. I don't tig weld so I was looking at using nickel rods and arc welding it with a preheat and then slow cool. Of course I will be doing it in the middle of summer when it is really hot. I will be welding about and inch to an inch and a half skipping around but peening after each weld. What do you think my chances are I will have success?
@@dolphincliffs8864 Everyone knew what he meant. No need to be pedantic. Daniele: Cast iron repairs are often unpredictable but i think you have a good chance of success if the damage is just in the water jacket. It's already broken so you've got nothing to lose. I usually tig braze cast but I've had good luck stick welding with n99 nickel rods as well. Keep in mind that you'll use less amps for a given rod diameter than you would for normal welding. You need enough heat to get it to flow nicely but not to melt the cast. Make sure you actually get to the end of the crack. Sometimes the end is difficult to see. Dye penetrant is very useful if you have some. Preheat with a torch isn't always necessary but it's a good idea if possible. Good luck.
Preheat? Post heat? Peening? Never did cast repair with tig braze. Always preheated to 500f and used iron nickel rod. I always said two things make welders look bad. Cast and cracks. Would love to see some testing of the two methods. Sorry for being such a nerd. Aside from being a welder I'm also a CWI.
Hey can you guys do a video on SMAW 1G plate mistakes and how to avoid them? For example, i can run a 6010 on a flat plate, but when its in a groove, i just fail.
Nice, I love the science behind the instruction... I also have a 1971 Pontiac 455 H.O. with a broken lifter bore.... would you recomend trying this method in this application? that area will see alot of stress, I plan on using a lifter brace when I assemble it.
You really Make a lot of since. Have You ever tried a little Helium Mix In Your Cover gas. It really wets the Puddle and causes the Bronze To flow nicely and quicker than Normal.
Have you tried phosphor bronze on DC? I have tried Al bronze back to back with phosphor, and for cast iron, the phosphor seemed to be noticeably better.
Some things the gentleman got right a couple Very wrong. Stop drill, yes. Preheat, he got right. Unless you can preheat the ENTIRE casting, do not preheat. Localized preheating causes tremendous localized stresses. Never weld/braze on ground metal! As the gentleman stated cast iron has carbon, a lot of carbon. 1.5 to 2.0 percent. But the carbon precipates out of liquid as graphite in grey iron or as spheres in ductile or somtines also called nodular iron. When you grind, you smear the graphite all over the surface. So, ALWAYS, and with a clean sharp file, file over the ground area and use a burr to clean the groove. Now the choice of aluminum bronze is also wrong. Aluminum bronze has a small amount of iron in it. You can tell if something,like a propeller, is aluminum bronze by holding,from a string, a magnet close to it. The magnet will not stick but pull towards the piece. IMHO tobin bronze is a better choice of filler metal.
Hey would you recommend this type of rod for a marine long block , I got a crack on the long block the water side , some guy told me use nickel rod , your video was very good need more help
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Nice explanation and instructions on the metallurgical parts in the beginning. Thanks for sharing.
Yes, if you're a welder doing a range of jobs and on different materials, you'll become a little bit of a metallurgist automatically! Something of a mechanical engineer, too: The holes you drill to stop cracks accomplish that by spreading out stresses around the edge of the hole (instead of the tiny area at the point of the crack), reducing the stress concentrations that drive crack propagation. I like the explanation and the explainer. Would it have reduced crack risk in this repair if the block was modestly preheated and then covered with a blanket after welding?
Sir, your oral presentation is wonderful. The way you speak, no 'filler words', the confidence in the information. No dumb music. Thank you for letting me visit! Bill
Ive watched a LOT of welding instructional videos in my time. Most of them, the instructor blathers on about nebulous BS and you have to suffer through the nonsense to get to heart of the matter and even then they do a poor job actually being a teacher. This is, by far, the best instructional video (well, its up there with Jody's stuff) Ive watched. Not one second of this is wasted time watching, and every point made by this guy is on-point with this logic, metallurgy and materials-science conclusions. Well done sir.
I've been repair welding for 50+ years. I thoroughly enjoyed how you conveyed the information. Aluminum bronze is also my go to. The only thing I do differently is that I take a once over "cleaning pass" without any filler. I use lower amps, lower frequency, high reverse polarity to help pull impurities from the weld area prior to setting up for the actual brazing. I rebrush and acetone the entire area. Then I lower the dcep, slightly raise the ac frequency and start the brazing. My effort going over the area first with lower heat and higher dcep seems to result in less impurities floating out of the braze during the actual brazing of the crack.
Wow, I've been welding over 40 years, this is the BEST cast iron weld repair explanation I ever heard, very well done.
Thanks for your expertise😃
That was cool. I like this guy and the knowledge behind his welding. Also the fact we all are bad at stuff at first then we get better
Straight up info! Been doing this since I was 16 in 76'... with twisted wire brazing with a jeweler's torch. My uncle ran a Pressure Vessel shop and taught me how to do X- ray repairs guys twice my age mainly tried... lol.
Adapted from Eutectic filler to solid rods we center less ground, to Aluminum Nickel Bronze with proper 2 step preheat and gas adjusted by a progressive/regression type monitoring. Our contracts teaching D.O.D.
personnel has been a stellar advancement for " OUR BOYS ".
KUDO'S my friend... you are on point. Seth
I don't think I have ever heard a welding procedure explained so well.
Back in 87 at the community college to tie up our AWS cert & diploma we were required to do 80 hrs of community projects, labor was free, only charge on material if needed. Cost was a can of coffee, & a baker dozen from Dunkin donuts. Every thing from hard facing on dozer blades, rippers, rebuilding roller pins machine shop there would turn down, rewelding bicycles frames, rebuilding anything & everything... But this little Hispanic lady came in with a tortilla pan thats been in her family for four generations, had a hair line crack in the center, took for ever to get that carbon out of it.. but I did, ran two pilot holes to stop the crack, preheated, post heated, stress relieve, I forgot what rod we used, but it was very similar to hi Nickeli chromium base.. came out great, but when it came to getting the coffee& donuts, this lady brought in a complete home cook mexican meals for the entire shop.. Enchiladas Burritos, tacos refried beans, homemade salsa, fresh salad it was unbelievable what this lady & family did... 😊
I never welded before. This guy is the best teacher you have used so far. Some of us need this type of explanation of things.
If I may I'd like to share previous experience with cast iron weld repair. Certified 20+ years as aerospace welder/shop supervisor in the structures and powerplants depts and race car fabrication. As you have learned, being a welder means sometimes you are everyone's 'best friend'...
Running these depts I had a heat treating oven available for pre and post weld heating and cool down. Years ago, a cracked set of SB Ford heads were cracked. The 'old school' method suggested brazing with silicon bronze filler. Descale the area, stop drill the cracks, v-gouge the cracks, pre heat soak to 300+ deg. AC tig braze fill from both ends of cracks towards the middle with good overlap then slowly cool in the ovens. At about 6 hours with heads cooling near ambient temp, heard the awful sound of cracking!!! Repeat the process, eventually saved the heads.
A lot of time, effort for a maybe repair. There has to be a better way. Talking with a Eutectic sales rep, he suggested I try their special rod intended for cast iron and mismatched ferrous alloys, the Eutectic 680 filler. Available in tig and stick form. Intended as a specialty filler for difficult, unusual weld repairs. It has the unique ability to tenaciously hold onto the base metal but.. the filler puddle will 'relax' as it cools preventing post repair stress cracking. A somewhat low temp filler similar to your alum/bronze filler.
A friend racing a seriously modified Austin Healey Sprite in autocross his engine was in need of rebuild at a storied foreign engine machine shop. There you might find anything from a Fiat to a Ferrari engine overhauled, balanced and blueprinted. They magnafluxed the head, found it cracked between cyls 2-3. Very common... two siamesed exh. valves side by side with no cooling passage between them and they both share one common exhaust port. A disastrous design doomed to failure.
The machine shop owner said 60% or more of the BMC 850,948,1100 and 1275cc series heads all share this trait, showed me a stack of cracked heads with this, all deemed unrepairable and that good useable heads were becoming very scarce.
Decided to give the Eutectic filler a try. Carefully v-gouged the crack until it seemed to end, close to 5/8ths inch deep. Heat the area with a torch, inspect with magnifying glass to ensure the end of crack is found. AC tig/braze with the filler, not worried about excess build up. The machine shop will take care of that.
Head returned to machine shop, passed magnaflux test, shop milled and ground repair area, installed hard exhaust seats, repair deemed successful. I did 6 more of these heads for the machine shop at $100 each, all successfully repaired.
A Harley owner with old cracked knuckle heads came in that had been very poorly repaired at a high cost asked if I would try to fix his heads. Not a Harley fan, didn't give the loving care I had the others I found some of the nastiest, dirtiest cast iron ever encountered. Pockets of sand, oil that would explode while welding, grind back, try it again. Like it or not, the repairs worked.
To this day I consider the Eutectic 680 a 'wonder rod', seems able to hang onto, weld virtually anything of a ferrous base metal.
Maybe this could be also added to your arsenal of repair fillers for difficult situations. YMMV...
Nice video and explanation! Not long ago I TIG welded a cast iron exhaust manifold for a Kohler engine. I used stick cast iron rod (Ni rod) and cleaned off the coating. Pre heated the part to about 350 degs. Like you I jumped around the part to minimize stressing. I than heated the part again and put in in sand to slow cool it. I was surprised how well is welded except for a few pops due to carbon or voids.
Great process Cliff, I tried cast iron repair for a short time back in the early 90's while doing cracked cylinder head repair (mostly aluminum) at a machine shop I worked at. I bought cast iron rods our supplier suggested, and went to town with rose bud pre and during weld, sand to cover while cooling. Many tries, no joy. I almost bought a used pizza oven and then decided to keep brazing when possible and use an old method of drill and peen plugs in combustion chamber with success. Thanks for sharing your processes with me. Really challenging work. Happy to see people like you willing and able to save the old iron. Great job, Thank you.
👍Brazing is always the correct answer when it comes to cast iron repairs.. I've always used regular silicon bronze filler but I will have to try aluminum bronze next time.
Yes but no ..puddle gun is the answer ...
the strength of joint will be weak....dont think it is good option....we repair cats ironn by stitching
I like his reasoning about Using Aluminium Bronze because you run it on AC, and the AC action helps to clean out the crap from the weld area. Great Video.
Usually cast iron welding tutorials are all about pre-heat and post-heat and burying it in sand. I've never used TIG I just have some rain gutter to repair, this looks like the way to go. The rod isn't cheap but fixing cast iron is a valuable skill.
I agree, this video had very helpful details as to "why" cast iron is handled differently, too many generalizations are not useful in actual practice, details matter.
technically it's not a weld it's bronze brazing but that's still sometimes useful and water jackets-outside aren't stressed as much typically
i got a 426 hemi iron 1970 block that needs repairing/mod's and was hoping to avoid using gas-welding as it's not my favourite to use
Did you grind the cracks out 100%? I may have missed that detail.
@@tgreening You can see around 11:50 he ground a wide groove but not right to the base of the crack.
@@tgreening the goal when doing it is to have the welder getting to all of it and on the end's about 1/8 more so the crack's don't have a easy placement to start again
as far as over grinding yes technically possible but it just makes more time/work to fixing it but not enough and you probably will have to grind out the hole old weld you just did as it probably will crack the weld or close to it
One of the most interesting and informative videos about welding on TH-cam. Brilliant work. Keep them coming!!
Great job on the repair. Aluminum Bronze on cast is technically a low temperature braze as opposed to a "weld", which is usually the term used for a "Fusion welding". Now I can let gramma police take the rest of the day off. I was a professional welder (in another life). While I rarely had to weld any cast iron, I once had a situation where a large knuckle dragging pipe fitter, overtightened a cast flange that was NPT, meant to get threaded onto some galvanized pipe for an emergency shower system in a petro-chem plant and cracked it. The shutdown was over and the owner wanted the plant started up, but it would be weeks to get another flange (local suppliers don't stock cast #150 NPT flanges). There was some discussion about MacGyver-ing something up (the system only holds 100 psi warm water), but I said "Why don't we try silver solder on the crack and see if will hold?" With nothing really to loose, they said to give it a try and wait for it.........the repair worked find and for all I know it is still operating. The moral of story is, all repairs on cast iron are unique and what works in one situation may not be appropriate for another. If the joint I fixed was subjected to high heat or thermal cycling, the silver solder may on have worked.
Can't get enough.
Wake up to weld, go to bed thinking about the next puddle..
Love it man, keep it up.
A tip I learned is to not use grinder disks/flap disks on the cracks to be welded. The disks, apparently, create a gouge where the ground carbon fills the porous cast. This causes more carbon to migrate into welds. The tip I learned was to use carbide burrs to CUT out the crack, instead of grinding.
Yes! More from this guy! That was the most concise tutorial on cast iron I’ve seen.
This is awesome. Such a great instructor who explains it all so well. Thanks for the info!!
Just filled a small hole on some core shift that appeared during a gasket match on a SBC head. Did the standard 400* preheat with a slightly carburizing flame with a postheat, then insulated the structure for a slow return to room temperature. Hopefully to keep some ductility in the repair and eliminate the possibility of a crack. Used a 3/32" Nassau Brutus A electrode designed for spring, tool, and casted steel for the 1/2" repair area. Your video was great and very informative and reminded me of my college Metallurgy course with an emphasis on practical application. I will definitely try the aluminum bronze on a large structure repair next time where ductility is needed due to expansion and contraction during the heat cycling of things like an engine block. The use of a lower melting point filler material like aluminum bronze will be an advantage and minimize the heat affected zone of the repair. Great video and the knowledge shared was equally great!
From UK.
That was a brilliant comprehensive technical overview of the process. Clearly put and Thank You so much for speaking to us in such a well paced way. Great job.
I once worked in BTH, English Electric Steam Turbine Div. Willans Works, at Rugby town central England. The main product there was Prime Generator Turbines for public utility power companies. The large castings for steam chests weighed many tons and were produced in sand boxes in their own foundry. I reckon these weighed dozens of tons and like you say about residual stresses - they would crack on cooling. Multi million dollar item! The firm had welders based in the foundry ready to fix things. They used Bronze Welding (called Brazing in UK) and after QC X-Rays (& dye penetrant testing if I remember right) temporary gas fired oven (portable shields) were put round these monsters and specialist technicians in aluminised fire suits with I think water cooling etc would run the liquid gold magic silicon bronze into the prepared cracks. Yes the had ovens big enough to take the covers of a low pressure housing off a 600 Mw set. Preheat and bronze weld.
The firm is now part of General Electric I hear and there must be others out there who know that factory of the process and can correct me where I'm wrong on any details.
Keep the videos coming. You all got own styles and all of you are highly educational. Thanks!!
Decent fellow. America needs more people like that gentleman.
The most educational video I've seen on welding. Thanks Cliff, excellent.
I am a wood worker doing many things , I wish I was good like you at welding . Tank's , you are amazing to me .
Thank you for being articulate and knowledgeable on metallurgy
It seems welders now a days are getting more and more scientific and knowledgeable and it’s great.
Fantastic video, great explanation on the metallurgy of cast it’s always been something I’ve stayed away from welding. The Ol boys always Said “If you can’t cold stitch it, Scrap it” thank you for sharing 💪🔥🔥🔥
I didn't get anywhere near this level of detailed information when I took a welding class years ago. He would make a great instructor at a college or vocational school.
Thank you for a very informative video, very practical and down to earth and honest. What a genuine fellow, really cares about getting the practical info across and teaching the audience. Thanks again.
Just got done using this to fix my brand new $2000 block.. worked like a charm.. thanks for posting this! Welded very easy and clean as well.. it was on a part that broke off that holds a M8 head bolt at the top.. already machined and tapped and tq held way passed what is needed of it!
I just ordered a bunch of Al and Si bronze rods for just this 🤙 Thanks man! Great video and super informative. Cheers from Victoria BC
I love the explanation of materials and techniques as if the viewer was very new... because I am. It made total sense! Thank you!
I have used 10 lbs of brass on one repair several times. With great results. Fun stuff. Your correct the preparation is as important as the welding
I learned a lot from this video , I had no idea there is so many different types of cast iron . I do know cast iron is extremely hard to successfully weld . Awesome video . TO BE TRUTHFUL I WAS EXPECTING TO HEAR THE BLOCK CRACK AS YOU WERE FINISHING YOUR VIDEO .
Non welding person at all here. Best video I have seen so far and I have seen many. To say the least/most (🤔🤔🤔🤔, both a compliment) all I learned from this is that I will not be TRYING to repair my brothers block. It's the bolt hole for the starter, it has two cracks. So we were thinking HEY JUST USE A MIG WELDER AND TACK IT AND EVERYTHING WILL BE FINE. IT WILL PREVENT THE CRACK FROM SPREADING AND HOLD THE STATER IN PLACE, but no.
WOW, someone that understands metallurgical terminology but have never heard of using aluminum as a filling metal for a ferrous metal repair. I've been an aeronautical and heavy equipment welder for over 30 years (17 years as a certified Naval Aviation and shipboard welder) and have repaired numerous cast products but the use of aluminum is definitely different. 90% of the time I used a Nickel base filler metal whether (GTAW & SMAW) but always used a rose bud to pre-heat and post-heat after each welding process. But I will definitely look into using an aluminum base filler rod. Thanks for sharing your findings.
Cliff! Thanks for the shout out! Excellent video buddy!
No Problem!! Appreciate it!
All Great advice. I often use Silicon Bronze for cast repair but I'm almost never repairing engine blocks. Mainly manifold and such where it needs to be sealed but not structural.
Aluminum bronze is supposed to be stronger and harder. I've heard more elongation too, but not sure of that. Using AC (instead of DC that's typical for silicon bronze) should provide some cleaning action that will help cope with the impurities you'll face in old cast iron. Should only need relatively small cleaning action, maybe 10% EP vs the typical 25-30% that would be used for regular aluminum. BTW, I like the encouraging tone of this guy!
I've never given this a go on GTAW. On a LASER AlBr does quite well.
Thanks for the tips, good sir!
Wow, that was fantastic. Hope to see more topics from you, and I'm sure many others would agree.
Great instructional video, Cliff. Really great metallurgical explanation and welding demonstration.
Greetings from a trol! 😁 I welded a cast iron household water pump with aluminum bronze filler. That was 3 years ago. Never got a call back
Great information! Never thought about aluminum bronze for a cast iron repair? I am going to try it. Thanks from a fellow Yooper.
Best discussion about cast iron's carbon content and weld repair characteristics that I've heard. I tend to think bronze brazing due to elongation and ductility. I like the aspect of lower temperatue and its wetting actionwhich makes me 'feel' like it's really joining with the cast surface. No issues with repairs with bronze rod yet.
I learned something new. Aluminum bronze. For cast.
Sensational. You, my friend, are a true professional and excellent teacher. Cheers from Australia. Davo
Great presentation. You seem to know what your talking about. I would like to see you do a video on the same subject using nickle alloy rod. Thanks man!
I love videos like this. They've put me to the top of my apprenticeship class.
Can't wait to try aluminum bronze. I have tig weld with muggy 77 with good repairs. Welding cast aluminum is the same , great prep=a nice solid repair with no come backs .👍
Will definitely have to try this. Welding cast for me can sometimes be easy and go great. Sometimes extremely difficult. Definitely a steep and quick learning curve. But i haven't had any failed parts yet. Only failed attempts that i had to come at in different ways to complete.
Is this why brazing has been a go to cast iron repair for the longest time?
I wish you showed it after the welds were ground! Bet it was a beauty!
I bet it wasnt a beauty! he should leave it alone. the chance of it cracking got greater
The best results i have had welding cast has been with a stick welder using "Arctec #3" i have done brazing and acetylene welding cast iron, i have yet to try Tig welding cast, next time i will, thanks.
Thanks Cliff nice tutorial and treatise on the welding and prep!
Thanks for explaining this so a chimp like me can understand.
Great video, lots of info on the metallurgical part of welding. On side note, I had to weld a crack in punch press arm some time ago for the company i work for. We didn't had any ac capable welding machine just mig and a little dc tig welder, i chose to use the dc tig with 316 stainless as filler(of a mig reel lol) and its been fine for the past 3 months.
The difference between grey cast iron and nodular, or malleable, cast iron is the heat treatment performed. The carbon contents of both types are in the same range. The problem with welding cast irons is avoiding fast cooling rates that allow the formation of "white" iron which is basically Iron carbide or cementite. The when iron gets above a certain temperature there is a change in structure and the carbon goes into solid solution. If this structure cools too quickly, then a form called martensite forms which is very brittle. The key is to preheat the cast iron piece, perform the welding, then cool slowly. The area that he is referring to in the weld is called the heat affected zone or the HAZ. Rather than welding, an alternative process is to braze the crack. Also at the tips of the crack is to drill them out and insert a threaded plug. Nice job.
Thanks everything you said MAKES GOOD SENSE..
Excellent tutorial! I wish you were in Idaho. I have a 1938 Waterous pump housing, for a 1938 Ford Luverned fire truck, that froze and cracked at some point in its 84 year life. Someone tried to weld it and it appears to be herendously awful. I am not even close to having the skill to weld it but I wanted to educate myself as I look for someone to weld it.
You gave me a lot to think about in this one. I am just getting ready to ramp up repair on a large Athol vice with a broken 1" thick mount ear. Clearly, this is going to be outside my wheelhouse. Have any advice?
Great video man, I do a lot of cast and still learned something!!
Thanks!!
Great explanation!! I also have done many cast weld repairs including cast aluminum( which is a freaking nightmare) you were dead on in your description and methods.....I'm very glad you did such an in depth explanation...my only suggestion would be to go into a little more detail on the cleaning and grinding procedure. Great job!
Best Cast tig vid yet. Love the Al bronze.
I loved learning metallurgy. Just remember....brittle means cracking. Cast iron in general does not like going back into a molten state. I've thrown blocks into a home stove before because like he's stated, the best way is heating the medium. It's more difficult heating cast iron because you have a hot block or cylinder head's in my case but, it's worth it. At least from what I've seen and done.
No pree heat or post heat? I also use a needle scaler to blend in after final grinding, making it look like original casting. When painted you can't tell the difference. Good job 👍
Great info on this. I never knew about aluminum bronze because everyone always said use a nickel rod
I’m not a welder, have never welded, but have always had an interest in it. So now by utube I’m learning a lot about. I watch your site as well as others and hope to someday get a chance to lay down a bead. Not professionally but just to build my skill base.
Nice! Thanks for watching!
Teach yourself to fusion weld with oxygen/acetylene and the rest of the welding methods and materials will come to you naturally, oxy/acetylene (gas or flame welding) is overlooked as an outdated method of welding when in reality it is very effective, strong and versatile, to this day I still use gas welding often because it makes some jobs easier to perform than one of the modern welding methods.
@@Peter-V_00 Thanks for the pointers and the reply.
Carbon does not harden steel because carbon is hard in itself, carbon hardens steels because it interrupts the crystal structure. This can be thought of almost like how they add gravel and other aggregate to concrete to increase it's strength (Though they also add gravel as it reduces the amount of concrete needed by adding filler). Y'all always put out really great videos though, glad you make them as I am teaching a friend to weld as of now and have been using your videos to help cross reference my own knowledge from when I learned to weld. 2:48
Edit: Also carbon is only hard when in certain forms, things like graphite are quite soft while diamond or graphene are quite hard. Ceramics containing carbon are also generally very hard like the many types of carbide in the shop. Generally the carbon we encounter in our daily lives can be thought of as soft though.
Higher carbon content Does make steel harder. Haven't you ever heard of high carbon steel? Just drill a hole in it compared to drilling in mild steel, you'll see.
Nicely done,thank you for your wisdom.
Outstanding Video! Thanks Cliff.
Thanks for sharing your huge knowledge with us, very helpful and informative 👍
Dad was a farmer from Idaho he brazing rod and the torch not to much at once. I like alum bronz tech.. I've seen a needle gun used to hide repairs on cast end to pean for stress relief. 😩
You explained that just so well buddy and I understand the steels
Very interesting. I have welded cast iron using high nickel content stick rods, with pre and post heat and peening in-between the short weld beads l laid. The repairs have been a successful. I will try some of those rods if l can get them in the UK? Too stuff.
Absolutely loved this episode. Perfect and deep explanation. I learned a lot. Thanks.
Awesome. Great info and presentation. Thank you.
Well spoken, intelligent conversation. Hopefully those students above the bridge value those skills you will undoubtedly share. Eh?
Thank you Chris Anus I love aluminum bronze too. Great video cheers 💥🤟
I like detail and clear logical explanation
Thanks for the great tutorial. I am planning on repairing my Chevy 350 block that froze a few years back. I don't tig weld so I was looking at using nickel rods and arc welding it with a preheat and then slow cool. Of course I will be doing it in the middle of summer when it is really hot. I will be welding about and inch to an inch and a half skipping around but peening after each weld. What do you think my chances are I will have success?
You mean SMAW.
@@dolphincliffs8864 Everyone knew what he meant. No need to be pedantic.
Daniele: Cast iron repairs are often unpredictable but i think you have a good chance of success if the damage is just in the water jacket. It's already broken so you've got nothing to lose. I usually tig braze cast but I've had good luck stick welding with n99 nickel rods as well. Keep in mind that you'll use less amps for a given rod diameter than you would for normal welding. You need enough heat to get it to flow nicely but not to melt the cast. Make sure you actually get to the end of the crack. Sometimes the end is difficult to see. Dye penetrant is very useful if you have some. Preheat with a torch isn't always necessary but it's a good idea if possible. Good luck.
Excellent teacher! Thank you.
Good job Cliff, great info explained well
Preheat? Post heat? Peening? Never did cast repair with tig braze. Always preheated to 500f and used iron nickel rod. I always said two things make welders look bad. Cast and cracks. Would love to see some testing of the two methods. Sorry for being such a nerd. Aside from being a welder I'm also a CWI.
Hey can you guys do a video on SMAW 1G plate mistakes and how to avoid them?
For example, i can run a 6010 on a flat plate, but when its in a groove, i just fail.
Hey mate..great expenation will a silicon bronze be adequate for small cast welds, say a small vice..
Yep, preheat it first, and wrap it afterwards so it cools slowly, or bury it in dry sand.
Nice, I love the science behind the instruction... I also have a 1971 Pontiac 455 H.O. with a broken lifter bore.... would you recomend trying this method in this application? that area will see alot of stress, I plan on using a lifter brace when I assemble it.
Great video! I remember peening the weld on cast iron when using nickle rod! I like the tig weld with aluminum/bronze filler!
You really Make a lot of since. Have You ever tried a little Helium Mix In Your Cover gas. It really wets the Puddle and causes the Bronze To flow nicely and quicker than Normal.
Have you tried phosphor bronze on DC? I have tried Al bronze back to back with phosphor, and for cast iron, the phosphor seemed to be noticeably better.
I have not! I will check it out
Super info, very helpful, thank you very much for sharing your knowledge 😊
Some things the gentleman got right a couple Very wrong. Stop drill, yes. Preheat, he got right. Unless you can preheat the ENTIRE casting, do not preheat. Localized preheating causes tremendous localized stresses. Never weld/braze on ground metal! As the gentleman stated cast iron has carbon, a lot of carbon. 1.5 to 2.0 percent. But the carbon precipates out of liquid as graphite in grey iron or as spheres in ductile or somtines also called nodular iron. When you grind, you smear the graphite all over the surface. So, ALWAYS, and with a clean sharp file, file over the ground area and use a burr to clean the groove. Now the choice of aluminum bronze is also wrong. Aluminum bronze has a small amount of iron in it. You can tell if something,like a propeller, is aluminum bronze by holding,from a string, a magnet close to it. The magnet will not stick but pull towards the piece. IMHO tobin bronze is a better choice of filler metal.
Hey would you recommend this type of rod for a marine long block , I got a crack on the long block the water side , some guy told me use nickel rod , your video was very good need more help
The teaching was way better than those welds. Thank you for sharing tho.
Very nice video. What about using Silicon Bronze? Thanks
Both Aluminum and Silicon are two great choices for a cast repair. Both have a high probability of success!
Thanks so much for the video, very informative!
Amazing video, very helpful, thank you.
always learning thanks
Great job! Super advise
Never thought of the idea that not melting base material would be a better idea.