Frame rail crack help needed

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First would like to say Hello as I am new.  Also, I have welded a few times but still considered a novice.  My friend has a nice Miller mig welder 220v.  He says if he can he would like to help but has never done a repair such as this. .  I have a 97 Mack RD688 Tri Axle Dump Truck.  This truck is rated at 80,000lbs. fully loaded.  I bought the truck about 8 months ago and was taken for a major ride by the previous owner.  He or someone touched up a break on drivers side in frame rail that could be seen so it was very hard to detect.  I am going to post pictures below.  The crack is almost directly in the middle of the lift axle bracket which covers about 2/3rds when bolted onto frame.  This truck has a double frame on it. And the crack, or actually break is completely threw both rails.  I have had 2 guys say they could fix it by V grooving and welding it up.  There was a fishplate on the inside which was 1 size smaller than the inner frame rail and was bolted in there.  But they cut it in between the crossmembers which makes no sense to me.  The two guys I had weld it up said they did not see any reason to extend a fishplate as the weld would fix the problem.  Wrong!  It was fixed actually 3 times and has cracked everytime after.  The rails are 1/4" thick and 1 inside the other.  I would like to know how you guys would go about fixing this.  I am in South Jersey and no one around here seems to know what they are doing with this kind of fix.  Any help would be appreciated.  One pic is the outside frame rail which you can see part of the lift axle bracket in at bottom of pic.  Other is pic of inside frame rail.Oh and by the way, you will see a pc. of 1/4" angle that the first welder welded on the top of the frame rail.  He talked a good game, but.  When I saw it I laughed.  Then I told him you are the welder, not me.  I said even I know you are not suppose to weld anything on the top or bottom of frame.  I left him and did not pay his feable attempt at fixing. Attached ImagesLast edited by jeffl1107; 02-21-2011 at 04:52 PM.
Reply:I would'nt touch that with a 10 ft. pole Good luck though what ever you decide to do.Ya gotta spend money to make money!
Reply:I'm with Shane on this one.  I'd never work on that frame.  If it were mine and I had to repair it for myself (basically, if the truck was the only way I made a living and I couldn't afford to replace it), I would do the following:strip the frame to bare metal for at least 12" on either side of the crack.grind out the crack from both sides, weld it from both sides with 10018build a 1/4" thick reinforcement plate that wraps that whole section on frame for 24" (12" to either side of the weld)cut diamond shaped welding sections out of the reinforcement wrap and weld the whole thing in place around the frame.After that I'd keep it only until I could afford to replace it.--Wintermute"No man's knowledge here can go beyond his experience." - John Lockewww.improvised-engineering.comManufacturer Agnostic:Blood----------Sweat---------Tears----|------------------|----------------|----Lincoln Red, Miller Blue, Esab Yellow
Reply:My best friends Truck is set up the same way with the double frame.   He does not have the drop axle on his Pete.  He also has a removable dump box so it can convert to a semi.   I did some welding on his frame for him when I moved back from California.     To say the least I did not just jump in and say I'm going to weld up your frame.  I was very careful about everything I did and did some research because peoples lives are at stake.What I'm getting at is that is a VERY SEVERE Crack as you know and if its been welded on 3 times then more work needs to go into it than just some guy filling the crack and saying good luck.   I know you need your truck back on the road but if that breaks all the way thru next time while your driving it may not be just your life at stake.   If your were in Portland I'd take a closer look.    You seriously may need to look at a new truck and get what you can out of your old truck in parts and scrap metal.“I'm going to do the thing that God put Galen Beasley on this Earth to do:Have Salon quality hair and weld.Nothing like a good cup of coffee and the smell of 6010 burning in the morning. 971-204-3444 cell API ASME Structural NDT and Repair
Reply:Ok I have a really dumb Question what about bolting  two heavy pieces of steel on both sides of the frame and don't weld anything .   Huge gamble  but just a thought
Reply:I fixed a couple truck frames before.  I learned from an old school welder that never had any problems with his repairs.1) Do NOT mig weld on frames!2) Arc weld DC + with 70183) Use T 1  1/2" plate.  (width of the T 1 is the inside of the chasis channel)4)  go at least 3ft on each side of the crack.5) taper end of T 1 and round off the point6) straighten the frame using as many points of reference as possible7) bolt the T 1 plate to the inside of the channel using as many existing bolt holes as possible (grade 8 bolts)8) open the crack up. weld it up. use the T 1 as a backing plate.9) weld the T 1 to the chasis. burn a rod. move to another spot. (skip around, to spread heat around)IMPORTANT: don't weld around the rounded point of the taper on each end.  This allows flex in the frame which is important.10) Good luck.
Reply:Originally Posted by infroOk I have a really dumb Question what about bolting  two heavy pieces of steel on both sides of the frame and don't weld anything .   Huge gamble  but just a thought
Reply:I have welded lots of frames with success, this one is a little tough but I would air arc the outer frame off as in drawing being careful not to nick the inner frame. Repair the inner frame with a 100% weld, use copper backup and plug weld all the holes, grind outer flush and fish plate the back if possible. Next use 1/16" copper stripes between the inner and outer frame, have a new section of frame formed to fit. Leave a  1/4" gap on both ends and fill 100%. Use a frame drill to drill new holes for tag axle. IMO Attached ImagesI always tried to work with the oldest hand on the job to gain knowlege but now I can't find any.
Reply:Definately repairable BUT - you're going to have to split those joints up by replacing a section of or entire inner frame to do so.I presume it's a pusher axle rather than a tag which would put the cracks approximately half way between the rear suspension and back of the cab and as such the area that experiences some of the most frame flexing.To do it right the rig's going to be down for a while even at a shop that knows what they're doing.Guess I should have read all the replies first.  digr's method is similar to what I was thinking but on the outer rail and in much greater detail.Last edited by duaneb55; 02-21-2011 at 07:39 PM.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:Originally Posted by digrI have welded lots of frames with success, this one is a little tough but I would air arc the outer frame off as in drawing being careful not to nick the inner frame. Repair the inner frame with a 100% weld, use copper backup and plug weld all the holes, grind outer flush and fish plate the back if possible. Next use 1/16" copper stripes between the inner and outer frame, have a new section of frame formed to fit. Leave a  1/4" gap on both ends and fill 100%. Use a frame drill to drill new holes for tag axle. IMO
Reply:Originally Posted by lars66I think this repair is work able but, only after the cross members have been checked for cracks, they tend to break out toward the ends where it is almost impossible to get at to do a good repair. The only way they come out is out the back because they are one piece.
Reply:Originally Posted by digrI have welded lots of frames with success, this one is a little tough but I would air arc the outer frame off as in drawing being careful not to nick the inner frame. Repair the inner frame with a 100% weld, use copper backup and plug weld all the holes, grind outer flush and fish plate the back if possible. Next use 1/16" copper stripes between the inner and outer frame, have a new section of frame formed to fit. Leave a  1/4" gap on both ends and fill 100%. Use a frame drill to drill new holes for tag axle. IMO
Reply:This can definitely be repaired. I have done some like it. I won't say how since there are so many interweb experts here that like to pull everything apart with zero or little experience.  I go by the engineers that designed the frame in the first place.I will say some of the advice is solid. Some isn't. If you want the best advice for welding on a particular chassis frame, go to the manufacturer and see what their engineers will allow as to joint design and welding parameters. They already know what will work and what won't and exactly how they want it done. I weld Class 8 frames regularly with MIG as per the engineers instructions and allowable processes and parameters. It is NOT rocket science if you are a proficient weldor. I mean, how do you think they weld the things in the first place? Production work is not done with sticks.QamuIs Heg qaq law' lorvIs yInqaq puS
Reply:Concur, check with Mac. It's their frame, they have done all the homework.City of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny
Reply:Hi all! i am going to hit you guys from left field here ,i have some cousins that are farmers and they own a couple of old macks and they love em,one of them is a grain truck with a big dump bed "i don't know what model or number but it is allot older than yours " they had the same problem several cracks ,several repairs ,nothing to repair anymore but you know farmers they won't get rid of anything so they decided to get 2 new pieces of channel the whole length of the stock chassis   and used the existing frame as a template and drilled all the holes then discarded the old frame and  fastened the cross members  in like they were done buy mack  . i know this is a helva allot of work "because they said so" but for something that's been patched and welded several times chances are good it's going to crack again some were else[ you know metal fatigue] just my 2 cents ..good luck chris
Reply:Ordering new and custom-length rails is common and you can find suppliers online. Lurk the Tow411 forums for some serious big truck mod info. If I were doing this I'd buy a Hougen drill kit for the job. If I were doing this for a customer, the job would pay for the Hougen and then some. They are sweet, sweet tools for that sort of work.
Reply:i think digr has the best plan, but i would splice a new section into the inside rail as well.looking at the pictures, that rail isn't just cracked, it's fractured. you have to cut out the rot.i work industrial construction, if you ever get caught downhanding 7018 on structural steel, or running straight polarity, you are history... big time.the mig vs stick question came up in a metallurgy class i took once, we were taken through detailed mathematical calculations that showed specific heat input (in jules) and the low-alloy steel heat affected zone problems relating to that heat input, and the comparison showed why wire feeders are the only processes used on professional heavy equipment frame repair. (and tight stringers only)having said that, my old dodge w200 just gets a couple passes of 6010 downhand evey couple years. (off road only)Last edited by rjm; 02-22-2011 at 02:10 PM.
Reply:I was under the impression that those frame rails are hardened steel, and are not to be welded on.I think calling the manufacturer would be good. Need more info.What about a new frame? It would cost less than a new truck. Depends on the labor.AWS certified welding inspectorAWS certified welder
Reply:Never done frame work myself, but manufacturer docs are a great place to go. Its already been mentioned, and I would like to toss in another vote. Service manuals usually say something about repair criteria and procedures. With a crack like that I would pay super close attention to criteria. These manuals are expensive but very much worth their salt.In addition, look for "body builder," "outfitter," or "upfitter" guides. These are intended to be used by the aftermarket shops that do things like modify frames. (On the surface I am thinking limo, RV, etc. but could involve all sorts of other vehicle types as well.) They offer guidance on what are acceptable types of frame modification, which can supplement the acceptable methods of frame repair in the service manuals. Adapting an acceptable frame modification to support an acceptable frame repair only makes good sense. In addition I was able to find a number of these guides online, free download (except Mack).GM - http://www.gmupfitter.com/publicat/Best_Practices.pdfFord - https://www.fleet.ford.com/truckbbas/Mack (not free... $30) - http://www.macktrucksemedia.com/Prod...ProductId=6196These vehicle specific manuals also have a huge plus going in their favor. They give best practices for the specific vehicle at hand. These are fabulous if you have to use a certain type of filler, settings, certain prep procedures, etc. For example, is the frame heat treated? If so, how/what method? Frame alloy weldable? Acceptable processes? In other words, a lot of questions that it might be easy to guess wrong on...
Reply:Originally Posted by rjmi think digr has the best plan, but i would splice a new section into the inside rail as well.looking at the pictures, that rail isn't just cracked, it's fractured. you have to cut out the rot.i work industrial construction, if you ever get caught downhanding 7018 on structural steel, or running straight polarity, you are history... big time.the mig vs stick question came up in a metallurgy class i took once, we were taken through detailed mathematical calculations that showed specific heat input (in jules) and the low-alloy steel heat affected zone problems relating to that heat input, and the comparison showed why wire feeders are the only processes used on professional heavy equipment frame repair. (and tight stringers only)
Reply:Originally Posted by rjmi think digr has the best plan, but i would splice a new section into the inside rail as well.looking at the pictures, that rail isn't just cracked, it's fractured. you have to cut out the rot.i work industrial construction, if you ever get caught downhanding 7018 on structural steel, or running straight polarity, you are history... big time.the mig vs stick question came up in a metallurgy class i took once, we were taken through detailed mathematical calculations that showed specific heat input (in jules) and the low-alloy steel heat affected zone problems relating to that heat input, and the comparison showed why wire feeders are the only processes used on professional heavy equipment frame repair. (and tight stringers only)having said that, my old dodge w200 just gets a couple passes of 6010 downhand evey couple years. (off road only)
Reply:Originally Posted by lincweldI fixed a couple truck frames before.  I learned from an old school welder that never had any problems with his repairs.1) Do NOT mig weld on frames!2) Arc weld DC + with 70183) Use T 1  1/2" plate.  (width of the T 1 is the inside of the chasis channel)4)  go at least 3ft on each side of the crack.5) taper end of T 1 and round off the point6) straighten the frame using as many points of reference as possible7) bolt the T 1 plate to the inside of the channel using as many existing bolt holes as possible (grade 8 bolts)8) open the crack up. weld it up. use the T 1 as a backing plate.9) weld the T 1 to the chasis. burn a rod. move to another spot. (skip around, to spread heat around)IMPORTANT: don't weld around the rounded point of the taper on each end.  This allows flex in the frame which is important.10) Good luck.
Reply:Send a message to Neil..(wello)..He deals with broken twisted bent heavy duty frames all the time..He is your best bet here.....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:What Zap said.Ranger 250 GXTSmith Gas Axe
Reply:Jeff this the way i would go around repairing this frame I have done this many times in the past and the rail can be mig welded we use ESD209S wire have done for a long time first of i would remove the inner rail 3ft past the crack and run a new rail inside to repair the outter I would do it like in this crap pic I drew welding the insert piece both sides and fit the new inner rail like in this other crap pic of course welding the join and remembering that mack bolts are a very neat fit it you use mack bolts to replace boltsin any new holes you drill you may need to ream the holes for the bolts to fit right there may be others that don't agree thats cool its just way I do it and have been for the last 25yrs you may be able to get a section of inner rail from a truck wreck that matches the hole pattern in your rails and that will save you a heap of work drilling because mack rails are a pig to drill Creative metal Creative metal Facebook