My buddy and I were having this discusion on spring steel. Can it succcessfully be welded? Is there a proper way too weld it? Does it change the steels properties? I have no idea. Anyone?
yes. yes. yes. Spring steel is like tool steel. You'll have stress cracks and possibly breakage at the weld if you don't preheat the whole thing, and even then it might not hold up, but if you are just using "spring steel" to make a bracket or art, it will be fine. My college roomate was an engineering whiz, he gave me the basic rundown
Need to explain what you plan to weld (bumper braces,etc?). Go to millerwelds.com Miller Electric has an updated motorsports web site that has a question and anwer section that might help.
You can weld it, but I think the heat of the weld will anneal the steel in the area right next to the weld, which will make it softer and weaker at that point. The filler metal probably won't be as strong as the spring steel either. How they harden the spring steel depends on the alloy, but I think usually it's heated very hot to some specific temperature or color and then dropped into a vat of oil to quench it. How hard it becomes is dependent on how much carbon and other things are in the steel and how fast you cool it down. If you cool it too slow, it comes out soft, and if you cool it too fast it comes out brittle like glass. Spring steel is a little brittle, but not as brittle as something like the tip of a cutting tool. I think if you wanted to repair a broken spring, you'd have to preheat the whole thing and then use a special filler metal and then heat the whole spring and quench it right for it to be usable again. I wouldn't put much faith in something like a leaf spring that's been welded back together unless the guy doing it was a real pro at it.
i would'nt recomend trying to repair a broken spring but when i worked in the spring shop there were sertain heavyduty truck springs that we had to weld a threaded bushing into so it would'nt turn in the spring eye. we had a special stick for the arc welder that we used. i totaly forget exactly what it was but you local welding supply shop should be able to help you out there. if you go MIG i think you need a different gas or gas mixture and possibly different wire. it's been a few years so i'm fuzzy on the details. we actually made leaf springs in house from scratch. it was a special steel to start with then it was cut to length and if it had a spring eye or other bend in the end the end was heated in a furnace till was REALY red. then it was rolled or shaped around a die. after that it was put in another oven (the entire leaf) where it was heated to a specific temperature then pulled out and placed over a curved form (different curves for different springs) then clamped at either end. it was glowing red so it easily bent to the shape of the curve and then a little water was sprayed on it to cool it slightly. this part took a real knack to get it right cause depending on how much water you put on it it would hold more or less of the curve you had it clamped to. after that it was unclamped and quenched in a special oil. when they came out of the oil they were placed in a "draw furnace" where they would go through on a conveyor belt and be kept at a certain temperature for a certain amount of time. when they came out the other end they would be placed on racks and left to air cool the rest of the way. a bit more than you asked for but that the process. if you want to weld to it use caution and talk to your welding supply house about the right materials to weld to spring steel.
OK, time for an official metallurgy lesson. Spring steel is typically high carbon, and heat treated. So, to weld it you must use pre-heat. Pre-heat temp depends on the amount of carbon in your steel. The cool-down also can affect your weld, but not as critical as the pre-heat. No pre-heat and you almost certainly will get cracks along the fusion line. This is related to the same reason cast iron is such a difficult metal to weld. The high carbon content makes it hard to do successfully. Welding it will mess up the heat treatment in the area around the weld (called heat affected zone). If you want the weld to have similar properties to the base metal, you need special filler metals. The reason spring steel is oil quenched is that it needs a slower quench to avoid cracking. But the whole piece is heated up and then quenched. Not a scetion. Then it is tempered (what Kustombuilder called the draw furnace), to bring the hardness down and bring back some ductility.
I found the front spring eye on my '61 Comet was broken off half way round the bushing: I asked on here about welding the spring and 1/2 the responses said it couldn't be welded so I went with the other 1/2 that said -"What the hell, give it a try...". I found a piece similar size and thickness of square tubing, cut it and "formed it" : - Migged it in there with the Hobart 135: After a year of drivin' the sh%& out of the car and bad wheel hop' burnouts the poor springs are bent between the eyes and axles but the weld has held up fine. Powerband
Looks like you got a pigeon roost up on top of your spring eye. By the size of those piles of bird shit I'm guessing its a damn good sized bird!!!!! For all intents and purposes YOU should not be welding spring steel if it is for the road applications. IT WILL FAIL!!! There is a process to weld it, but even then you still have a fairly significant # for failure rate. The reason being that the spring steel and the weld filler have different properties, and will "FLEX" or spring at different rates. At that line where the filler meets the base metal, in this case "spring" steel it will develope stress fractures and at some point suffer catastophic failure.
Something about the carbon content in the steel & the migration when heated, and forming of larger inclusions of carbon, that are places where it can crack at lower stress levels.
listen to 38chevy454. he knows what he's talking about. Powerband's spring may have held so far, but he's been very lucky. the eye of the spring is under relatively low stress in relation to the rest of the spring, ie. part of the spring that doens't do much springing. if you tried just mig welding like that across the middle of the spring, it's useful life would be measured in minutes. ordinary mig weld has very little carbon in it compared to spring steel. the problem in welding it like that is you have a transition area between the weld that has little carbon, and the parent material that has a lot of carbon, the transition area will be highly stressed. in fact, because the mig weld will cool so fast, the spring steel near the weld will be even harder than the rest of the spring and, in the example of a broken spring, will be even more brittle than the spring was originally.
My welding is pretty crappy anyway but I intentionally tried to sew high penetrated "Buckles " across rather than butt weld the spring and the patch piece. You are right that there is not too much stress in that location but I like to use it as an example that: 'ya can't say it can't be done... Powerband
The main reason that you preheat high carbon steel before you weld it is to put enough heat in the surrounding steel so that it doesn't quench the welded area to quickly and cause "short" cracking, it also can reduce the stress that may be put into the weld when it cools and shrinks. I have seen welds on high carbon steel where the crack would follow the behind the weld puddle by about a 1/2 inch. As soon as the metal became cool enough to get hard it would crack. Also your filler rod is usually lower carbon than say a spring steel, that can be any where from .5 to .95% carbon and when you weld it with a low carbon filler while the metal is still molten some carbon will migrate to the filler metal and actually make it stronger. Not as good as the base metal but better. DON'T WELD SPRING STEEL IF YOU ARE GOING TO USE IT AS A SPRING!!! Rex
This is the kind of shit that get's people killed or at least hurt very badly and ends up giving hotrodders a bad name, man if you don't know what you are doing don't go experimenting arround with stuff that is dangerous! Damn, and I bet you even think this is cool or funny in some strange way! I can't believe some of the stupid shit people do to their cars!
- ?? - : Uhh, Isn't that what it's about here on the HAMB?, talkin about fabbin' and repair ideas with others, learning from experience, and then givin' it a try yourself, not paying some guy to work on your car while you polish the knobs. ... The spring was welded and it's worked fine for over a year, that's cool . Damn, I'm proud of it.. Powerband
single pot master cylinders work fine, right up until they don't. I have new springs and a dual master. I'm proud that my car is safe at 100 mph. I think that's a little closer to what we're about. .02 And since that is not a load bearing part, its a bad example of the overall point of this thread. When done properly, in a controlled environment, with knowledge of metallurgy, you can successfully weld a spring. You can also use spring steel for other means, weld it and have a good quality... whatever. But, welding spring steel is tricky, and should be left to pros.
When I first started at my job at a construction garage, There was an old time welder that used to weld broken leaves in Mack camel back springs. Never welded the main leaf, but would weld the others. Some times it would work, other times it would not, Being the younger new mechanic, guess who had to change the spring with the broken leaf, that experience pretty much soured me to spring welding tc
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