Truck frame cross members

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This is a 1991 Ford Super Duty bucket truck I picked up for $1,200 to use around the house and shop next summer for home maintenance. The truck is originally from up state NY and has some serious rust issues on the back half of the truck. The heavy rust is isolated to the back which was under a service body (the service body was a total loss from rust). From the back of the cab to the front of the truck the frame is fine, light normal surface rusting. The pictures tell the story but to put some of it in words I rubbed every square inch of everything with an air chisel to remove the heavy rust and then gave all that a once over with a wire cup brush on the angle grinder. I cut out the back 4 cross members which were to far gone to repair and constructed new ones. The cross member between the front perch springs was major construction using ¼” plate and a 6x13 C-channel. The others are 3/16” plate. The goal is to make the truck safe for use again without fear of the frame twisting in two when I’m 35 feet in the air. Attached Images
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Reply:Excellent work! I'm amazed at how good the spring hangers look. They usually look like the cross members. "Every choice you make will effect at least one other person"
Reply:Nice work. A good example of how to do a repair like this. Noob's take note of the bolts used to install the cross members and spring hangers in place of the original rivets as opposed to welding on the frame itself and possibly compromising the frame..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:great work
Reply:Looks like that will be the last time those are replaced. Very nice work."Where's Stick man????????" - 7A749"SHHHHHH!! I sent him over to snag that MIC-4 while tbone wasn't looking!" - duaneb55"I have bought a few of Tbone's things unlike Stick-Man who helps himself" - TozziWelding"Stick-man"
Reply:Nice save of a true "Rust Bucket". I'm all too familiar with what Upstate NY road salt does to vehicles.  Excellent work. 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:What was the miles on this machine? a billion? I live in Ontario and that rust is bad. I would have wrote that off as a rusted out POS. But you got a fair price for the lift and the truck was thrown in for free. SO good buy,good save and you got a truck too.Miller thunderbolt 250Decastar 135ERecovering tool-o-holic ESAB OAI have been interested or involved in Electrical, Fire Alarm, Auto, Marine, Welding, Electronics ETC to name a just a few. So YES you can own too many tools.
Reply:Originally Posted by DSWNice work. A good example of how to do a repair like this. Noob's take note of the bolts used to install the cross members and spring hangers in place of the original rivets as opposed to welding on the frame itself and possibly compromising the frame.
Reply:Originally Posted by dumb as a stumpWhat was the miles on this machine? a billion?
Reply:That is some serious rust. Very nice job on the repairs. I would have been frustrated before I even started.Gordhttp://gordsgarage.wordpress.com/
Reply:So the idea is to bolt it in instead of welding it in so that the heat from welding doesn't pull the frame out of alignment?Also, that bucket of rust is crazy!!Thanks for sharing, Luke
Reply:Originally Posted by TaidenSo the idea is to bolt it in instead of welding it in so that the heat from welding doesn't pull the frame out of alignment?
Reply:Originally Posted by DSWNo. You use bolts so you don't alter the structure of the frame metal by welding. Many newer frames are high tensile steel and often are tempered or heat treated. When you weld on the frame you can destroy those properties. Not only that but E70 electrodes are usually wrong for that type of steel. Often  special high tensile electrodes can be spec'd as well as special pre and post heat for the weld. Use of the wrong techniques can seriously and permanently alter the metal structure in the heat affected zone of the weld. I've seen HT steel look like a cracked window from all the stresses induced by improper welding procedures when someone tried to do a repair. Even on older frames, it's usually best to stick with the same technique the original manufacturer used, in this case mechanical fasteners rather than welds.
Reply:The 64,000 dollar question is whether the bolts were installed correctlyRivets are heated, then distorted to fit the hole perfectly with no slop, and they're smooth shouldered.  Rivets are OEMWhen replacing rivets with bolts, at the very least, the hole should be resized to take the proper bolt size without slop.  If done really right, the hole should be reamed for an exact fit.The next consideration is the shoulder of the bolt.  Is it installed with the threads contacting the frame?  Ideally, the smooth non-threaded shoulder of the bolt should be the only thing contacting the frame (the closest thing to a smooth rivet), otherwise the threads eat the frame out in no time with the vibration and flexing.  Sometimes over-length bolts have to be installed to present a smooth shoulder to the wear area.  The thread doesn't come in contact with the relatively thin frame material.Movement, and steel to steel contact, have to be in mind at all times."Any day above ground is a good day"http://www.farmersamm.com/
Reply:Thanks guys, I appreciated the compliments. Yes, when I pulled the service body off my first thought was "wow, got a lift at a good price, now I just need to find a truck to put it on". But this is a "farm use" only truck, I'll never register it for the street so it just need to be tight and secure for use of the lift.Farmersamm: I get real excited when someone who shares my level for detail chimes in  Albeit, I did not go to that level of detail with this repair, so by admiitting that do I get the $64k?  Some of the larger/longer bolts did in fact have the shoulder (non-threaded) portion of  the bolt go though the steel but the smaller diameters did not. I used all grade 8 bolts with center punch lock nuts for this repair which is my standard. Also true is a rivet hole "typically" is not a standard bolt size and therefore should be drilled to the nearest accomodating size. In this case I used 3 different bolt sizes: 7/16, 1/2, 9/16. Also note worthy is a bolt will never be as "tight" as a rivet. A bolt can "clamp" as tight but the shaft of a rivet actually "expands" into the diameter of the hole when installed causing not only clamping but "horizontal tightening" too. The opposite can be true of a bolt which can "shrink in diamater if "stretched" too far.I have one more small repair which is replacing the lower corner of one more cross member. I should have it done today and will post a pic of it later.
Reply:Are you going to put the anti-sway bar back on? I would think that would help a lot in keeping the truck steady while you are in the bucket.
Reply:The BIG sway bar along with the small one will both get re-attached. The Bushings for the big one were worn bad and I found the source for them. The cost was $50 for the pair and should be here in a week or two.I finished the repair of the lower section of the final member. I used 2 pieces of 2.5x10x3/16 plate, drilled holes in one and "molded" the other in the vise with a hammer. The fitment was as close to perfect as I could have hoped to get. I did 3 passes to join the original member to my replacement piece. I brushed the original piece as hard as I could but there was still some rust that contaminated the weld. Overall I'm very satisfied with the finished product.These welds were done with my 110V unit, Hobart Handler 120, highest setting wire speed 7.5 Attached Images
Reply:Originally Posted by zapsterYep..As soon as I read the title the first thing I thought was "Oh no...No welding on the frame"Nice job there..Good to see salvage rather than scrap it.....zap!
Reply:Originally Posted by zapsterYep..As soon as I read the title the first thing I thought was "Oh no...No welding on the frame"...zap!
Reply:man these pics make me very happy that i live in a sunny warm climate where they dint lay down de-icer.Vantage 500's LN-25's, VI-400's, cobramatics, Miller migs, synch 350 LX, Powcon inverters, XMT's, 250 Ton Acurrpress 12' brake, 1/4" 10' Atlantic shear,Koikie plasma table W/ esab plasmas. marvel & hyd-mech saws, pirrana & metal muncher punches.
Reply:Originally Posted by Dualieman these pics make me very happy that i live in a sunny warm climate where they dint lay down de-icer.
Reply:Progress pics. I'm only putting the rear tank back in, the front is a metal tank and has severe rusting which I suspect will leak. The support brackets for the rear tank were completely rusted away. The only thing holding the tank up was the rusty remains of the "rock guard", which I also need to re-create. To get the tank out, all I did was push straight down and the tank pushed through the remaining rust and fell to the floor The new upper straps are 1/8" x 2" and the lowers are 1/4" x 2". All were bent up free hand on my HF bender. Not bad for "eye-balling" it.  Attached Images