Repairing Ibeam frame on old excavator. What do the experts say?

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I am in the engineering field but there are too many unknowns here and how I might "want" this fixed and what is practical are probably two different things.  Also due to the age and life remaining, I don't want over think this too much.  This excavator is mostly retired to limited farm duty but I might run it to a few jobs and don't want it falling apart on me.  I think these cracks have existed for years but obviously are going to continue unless stopped.  My thoughts were to try to find places to drill stop the cracks, then chamfer them out for full penetrations wells.  I think the flanges are about 1/2" but unsure on the webs.  Probably 1/4-3/8"I am also unsure on the best welding method.  My guts says this is a stick only job but I have seen a lot of heavy jobs done with MIG and we do have a 400A Esab that puts down some incredible welds.  I am also unsure how involved we should get with opening up the cracks for welding.  As I mentioned, I know this could get VERY in depth to do 100% correct but this might be more of a job to consider "good enough" methods or patches and reinforcements.  The pics will show what I am dealing with.  Any welding attempts were from a previous owner that obviously doesn't understand.  Like trying to plug a fire hose with bubblegum...  One of the flanges is starting to crack as well. Attached Images
Reply:V them out and have at it with 7018...May want to put a plate from the top edge to the bottom over where the cracked areas are....You have the room so why not?...zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:How would you attack the V?  I was thinking a grinder but there is several places to be welded so I was wondering about stick gouging?  I have never done it and maybe that will just be a mess?  What do you think on preheat?
Reply:If the web is 1/2" thick I'd V-it out from one side, about 30° on each side for a total bevel angle of around 60°.  The steel is probably low carbon, but the grinding will show you if the spark pattern suggests it's another material.  Assuming it's low carbon, I'd preheat to around 200F; just enough to make sure the steel is dry and avoid any cracking problems from rapid cooling.  If the ambient temp is over 50F and likely to stay that way you can probably skip the preheat step.You can gouge those cracks out to prepare for welding.  Just touch up the gouges with a grinder to remove and carbon buildup left over from the gouging process.  If you've never used an arc or plasma gouging torch, find some scrap to practice on.  Both remove material very quickly and a small slip while gouging can make for a large amount of welding to repair.  Grinding is slower, but easier to control.I forgot to mention, that you should grind or gouge out the back side of each weld and weld up the groove created.  This will ensure that you don't leave a pocket of slag that becomes the source for a new crack to grow from.Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector
Reply:If you are going to gouge it out clean the machine very well(oil,grease,leaves,paper ,anything that can burn)because there will be hot metal going everywhere .A fire watch would not be a bad idea.If using a grinder you will also need a die grinder and a carbide cutter to get where the flange and web meet.Good luck
Reply:The old weld repair looks poor. If this is an excavator frame or boom, I don't think it's low carbon steel. The old weld should be removed, crack opened or beveled, material cleaned     7018 would be minimum but I'd tend to think 8018 may be a better choice. Smaw all the way. Some pre heat won't hurt to sweat it out and slow the cooling process.JasonLincoln Idealarc 250 stick/tigThermal Dynamics Cutmaster 52Miller Bobcat 250Torchmate CNC tableThermal Arc Hefty 2Ironworkers Local 720
Reply:Originally Posted by fastlineHow would you attack the V?  I was thinking a grinder but there is several places to be welded so I was wondering about stick gouging?  I have never done it and maybe that will just be a mess?  What do you think on preheat?
Reply:fastline,Since you say you're unfamiliar with gouging here's a picture that'll help show you the kind of weld prep results you can get after you get some experience at using one.I doubt I had more than 10 minutes in making this prep and the only thing I did to it after gouging was run a needle scaler over it.
Reply:From what I can tell the cracks are in an area of high stress.  They are initiating near that bolt where there is a sudden change in section.  The area really needs to be cleaned and all the cracks gouged as mentioned. Some of the repair welds look like a dogs breakfast and likely you will see porosity that will have to be taken out.  Preheat and fire watch will be needed.  When you preheat you need to heat the whole area, not the cracks. If you cannot reach into the other side of the web you might consider gouging an open groove and slipping a 1/4 by 1 inch flat bar in behind then tacking it in place to act as a backing bar.  I like the suggestion of 8018.  If you put doubler plates in make sure that you do not create a stress riser at the plate ends.   Double check that the cracking has not gone into the flanges.  If there is and you only repair the web cracks will start again.
Reply:I would be tempted to cut out the bad section of web and weld in new material that way you can start with good edges. Fish plate it. A plasma cutter works well for gouging out cracks also.Millermatic 252millermatic 175miller 300 Thunderboltlincoln ranger 250smith torcheslots of bfh'sIf it dont fit get a bigger hammer
Reply:I was also going to mention plasma arc gouging as an option. Either way: carbon arc, grinder, die grinder w/carbide, maybe a little bit of them all. Drill out the ends,cut out all the boogers, bevel prep and 200 minimum preheat, 7018 for sure. I can't tell from the limited picture, but I would also think of just cutting off the whole end and putting on a new section if you have access above and below the flanges as I think that would be a whole lot faster and easier. BLSREPAIR good call on the fire watch! You know that thing has a lifetime of grease, diesel and hydraulic oil all over the place, one good hot spark and your crack repair is finished before you start.RyanMiller Multimatic 200 tig/spool gun/wireless remoteMillermatic 350P, Bernard/XR Python gunsMiller Dynasty 350, Coolmate 3.5 & wireless remoteCK WF1 TIG wire feederMiller Spectrum 375 XtremeOptrel e684Miller Digital EliteMiller Weld-Mask
Reply:Yep I'd gouge out the cracks, weld them up with 7018.Like mentioned plating over it wouldn't hurt either.-DoogieMiller 350PMiller Trailblazer 325 EFI w/ Excel PowerLincoln LN25 suitcase welderXMT 304/22a feederMiller Syncrowave 350LXMiller EconotigHobart Handler 140(2) Uni-Hydro 42-14Hypertherm 65 plasmaWEBB Gap bed lathe
Reply:Gouging out cracks is the only way I would repair.gussetting the web with 3/8-1/2" metal plates.and either diamond the ends of plates or rounding ends.  But don't weld ends all the way up. Leave a few inches not welded. Also we use a lot of 110-18 for high stress areas. Ping all passes of weld. And if you can get to backside backgouge. You should have 100%Sent from my XT1030 using Tapatalk
Reply:If I was going to be working on that the very first thing I'd like to see happen is for some one (even if it had to be me) to take a hot pressure washer to it.   Not only will that help cut down on any potential fire danger while working on it but it'd be my guess that once you start getting rid of those years worth of layers of built up grease and dirt you're probably going to find some more bad spots that could use some attention.  When it comes to welding my preference would be for some .045 dual shield.
Reply:Originally Posted by HT2-4956If I was going to be working on that the very first thing I'd like to see happen is for some one (even if it had to be me) to take a hot pressure washer to it.   Not only will that help cut down on any potential fire danger while working on it but it'd be my guess that once you start getting rid of those years worth of layers of built up grease and dirt you're probably going to find some more bad spots that could use some attention.  When it comes to welding my preference would be for some .045 dual shield.
Reply:The size mig he's suggesting is beyond most hobbyists. We are talking a 250 amp or better class mig to run the size and type wire he's suggesting. Most likely he's using a CV capable engine drive with a suitcase type wire feeder. A wire fed rig like that will lay down a lot of material fast. If you are doing a big job at a fixed rate, time is money.For the individual doing a one off project, stick gives you a lot of versatility. #1 it's not at all uncommon for the average person to own a stick machine capable of running 1/8" 7018. That's enough to do this job. If you are lucky enough to have a bigger industrial stick machine, you can run larger rods and save some time.Biggest issue I see here with a repair is if you can make good welds in all positions. Most people can make decent welds in the flat or horizontal fillets. When you get to horizontal grooves, vertical up, or overhead welds, they just make a mess. Welds like these separate those who can weld, form those who can't. Stick or mig, whoever does this needs to be able to make good solid welds in all positions..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:Have an Esab Migmaster 250 that is stated to push .045 cored wire.  ??  I love that machine!  Comparing to a baby Lincoln, I have never figured out what makes it so nice but I can always weld like a pro with it.  Better feed, power regulation or something.  Would that be good enough? I know with stick, I need more practice in vertical position.  I always seem to see my puddle running down rather than staying put.  With the MIG, I don't seem to have much problem.  Can I use an old 225 Lincoln AC for the carbon gouging?
Reply:The Esab should be enough machine to run that. The AC 225 probably won't do well trying to carbon arc. Duty cycle at the amps you need to run is probably almost nothing and you could cook the machine. You can gouge with a gas torch and the right tips, if you have the skill..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:What kind of power are we talking for gouging?  I have other machines available to me.
Reply:300 + amps,high duty cycle
Reply:Can a guy use smaller carbon or some way to reduce the amperage requirement and go a little slower?I read that the air/arc gouge can be applied to a MIG and feed air to the puddle to blow it away?  Would this be a better setup?  The Esab 250 can do 250A at 50% duty and I think 280A at 40%.Last edited by fastline; 03-25-2016 at 04:49 PM.
Reply:You have a lot of air arcing to do .You take a big chance cooking your welder.You could see how much it is rent a big enough engine drive welder ,Less then replacing the 250.
Reply:If you are doing the job yourself I would use the machine that allows you to put the best welds in you can. It does no good to use 7018 because everyone here says to use it if the turn out like the welds you just spent hours getting rid of. For a one time repair I would use grinders and a torch if you have it buy the time you buy a carbon arc and rent a machine to run it you'll be getting close to just having someone do itMillermatic 252millermatic 175miller 300 Thunderboltlincoln ranger 250smith torcheslots of bfh'sIf it dont fit get a bigger hammer
Reply:You could always go old school.  Attached ImagesDon’t pay any attention to meI’m just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:You need to take all that weld that I see in pics out. You don't want to have that mixed with yours. You'll be fighting a losing battleSent from my XT1030 using TapatalkOriginally Posted by CEPYou could always go old school.
Reply:Scarfing tips work great, but I’ll take a carbon arc over a scarfing tip any day of the week! I’m a very impatient person. I like to get it over with in a hurry.Don’t pay any attention to meI’m just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:Originally Posted by CEPScarfing tips work great, but I’ll take a carbon arc over a scarfing tip any day of the week! I’m a very impatient person. I like to get it over with in a hurry.
Reply:Originally Posted by fastlineAs you are the only one recommended MIG, I am curious if your reasoning?  To be honest, my arc experience is low so MIG would be my preference but was my understanding that arc is just superior when dealing with contamination? The machine has already been power washed but I will certainly do that again before repairs as I too see the potential for fires here. No doubt I need a fire watch and extinguish methods on standby.
Reply:Originally Posted by fastlineHave an Esab Migmaster 250 that is stated to push .045 cored wire.  ??  I love that machine!  Comparing to a baby Lincoln, I have never figured out what makes it so nice but I can always weld like a pro with it.  Better feed, power regulation or something.  Would that be good enough? I know with stick, I need more practice in vertical position.  I always seem to see my puddle running down rather than staying put.  With the MIG, I don't seem to have much problem.  Can I use an old 225 Lincoln AC for the carbon gouging?
Reply:This will help you with some of your gouging question.   http://www.red-d-arc.com/pdf/Air%20C...ing%20Data.pdf
Reply:If you have a 400 amp gouge with that. If you can find AC carbons you can use em but not on a buzz box AC 225. Your ESAB will run .045 Lincoln Outershield 71 M all day long CO 2 shielding that is  all we run ,used over 100 tons of it on the World Trade Center also in1/16".That is a multi process Esab and you could gouge 1/4 carbons with it or any CV/CC big welder.Clean out die grind all old weld out ,preheat 200 + use flux core or 7018 1/8 min or 5/32 ".Steel is A-36 or 572gr 50 on old equipment.
Reply:What make and model is it? Hein Werner ,Unit, Insley ,Drott?
Reply:Air arc out,dualshield Ultra-core 71A85 weld it up done.
Reply:Originally Posted by admsweldingAir arc out,dualshield Ultra-core 71A85 weld it up done.
Reply:That is not realy an i beam 2 flame cut flanges and 2 side plates so it really is a rect. tube arc gouge out the cracks weld with 7018 or 71-M and fish plate tie the fish plates to the flanges and taper the ends to a1 1/2" end don't weld across the ends but flare the welds lengthwise about 2"Sent from my SCH-I545L using Tapatalk
Reply:Originally Posted by HT2-4956Come on man, don't make it sound to easy.
Reply:Originally Posted by HT2-4956Come on man, don't make it sound to easy.