Bulldozer wishbone repair

[davo727]

Hello,

My friends JD 550 has a previous repair on the left side of the wishbone that the blade mounts to. It is plated on all 4 sides with 1/2 in plate where it curves around at the front towards the center blade pivot.

When I had it on my property last week clearing stumps I noticed the right side was cracked in the same area. It was not a new crack- I didnt do it I told him I would fix it since hes been a friend for ten yrs and he is giving me a great deal on using his dozer.

Got it here to the city house and found its cracked top and bottom on that inside curve and partway across the top and bottom of the arm.

Did a bunch of grinding today and stop drilled . Friday will make patterns and cut out 1/2 in thick doublers for it with plasma cutter. Top and bottom not a problem but bending .500 plates for the curved sides wont be easy.

May have to make some kind of steel buck to bend that inside piece over. I guess the outside one I could weld one end of it on and then heat it up and get some big C-clamps to bend the other end around ??

Figure on using DC rev arc for the welding, hows that sound? Dave

[davo727]

Some grinding on upper side

[norite]

Nice dozer and pics dave, I'd weld that with 7018 rod (electrode positive).

[davo727]

Gotcha, Thanks- DC reverse- is what I want to do. I goofed it up in my head and typed in EN in error thie first time, edited it now

[davo727]

Would it be good to lay in a first pass with 6011 DC rev? Or all with 7018 ?

[DSW]

My understanding is if you've gouged all the way thru and have an open root, you'll want to run a root pass with 6010/11 or use a backing strip (I'm assuming back grinding is out from the picts). If not there's a strong chance you'll have porosity issues with your 7018 root. On joints that don't have an open root you can run 7018 all the way.

[Scott Young]

What DSW said. On an open root you can use 6010/6011. I would then dress it up with the grinder again. Make sure you clean all the slag out. The next pass you want to run a hot pass with the 7018 and then fill and cap with 7018. I would rent a magnaflux unit before I start welding and make sure I had all my cracks found. you can often find a enginebuilder to rent one from or pay him to do it.

[Josh Flynn]

You need to gouge or grind the root open and place a backing bar inside. Then you put a good bevel on the plates with a feathered edge and run 7018 all the way.

[ironmangq]

For the 1/2 plate you could just tack one end and beat it to shape, welding as you go it might take a little doing and will be loud but it should work, might not even need heat. I have bent 3/8 this way quite a few times so I would imagine it would work just fine on 1/2 you might just need a bigger hammer.

[BlindViper]

whats the repair on the other side look like?

[davo727]

Cut the top and bottom .500 doublers out with the longevity 60.

[davo727]

Thanks for the advice, will do the best I can with it but no access for backing strip so I guess it will be6011 to close it up and then 7018 to fill the V . Then grind smooth and weld the doublers on.

[Scott Young]

read up on making a hot pass. that is the key to making the 6010/6011 root work and not needing a backing plate. the hot pass will dilute and/or release any hydrogen the 6010/6011 picked up.

as far as your doublers are concerned, I would make the ends shaped like diamonds. You don't want to carry a weld perpendicular the tube or create an undue stress riser.

[Josh Flynn]

There is no accses so you need to open it up with a gouger or grinder. If you get a 1/2in opening you can wiggle a backing bar into place. 6010 rods are great for many things but not heavy equipment. Also opeing the root up will give you greater accses and make it easy for you to clean all you slag out, you will also be able to use a larger rod for higher heat input which will also help with underbead cracks in you base metal and make for faster welding.

[Scott Young]

Josh, There are multiple ways to skin a cat. Shaping a backing bar to the inside corner radius of that tube along with the curve is just crazy. 6010/6011 is used on many applications. the only thing I would highly suggest is magna fluxing the area.

[AMillerUser]

davo727,

Please indulge us with some pictures of your gooseneck and tow vehicle.

Regards

[Josh Flynn]

[quote=Scott Young;507072]Josh, There are multiple ways to skin a cat. Shaping a backing bar to the inside corner radius of that tube along with the curve is just crazy. 6010/6011 is used on many applications. the only thing I would highly suggest is magna fluxing the area.[

I know 6010 are used everyday on many applications(i have used them quite a bit), but every rod has there own applications and strenghs. Its never crazy to do the job the correct way, but if you are set on a open root. Why not run 7016 which are rods designed for open roots, low-hy, and also higher tensile strengh. I know we all have are own ways of doing things and thats ok. Using a mag particale unit or dye pen would be great to check for surface cracks.

[davo727]

Thanks Josh for the info- I will try and get some 7016 for the next project. Already welded the roots closed yesterday with 6011 and peened the crap out of it with needle scaler Capped part of it with 7018 and it looked beautiful.

I finished preparing the 4 doubler plates last nt, but right now im in the middle of a double shift at my real job at the airport. The free bulldozer welding is just for fun. Will be four days before I can get back on the dozer job.

The 2002 F350, triple 12K axle trailer and JD 550G all belong to a friend of mine.

[Josh Flynn]

Always nice to have a project like that and a full time job matter a fact. Good luck with it and let us see some pics when you get a chance.

[davo727]

Bottom plate is mostly on, the inboard side needs several more passes. The outboard side is not too pretty- will try to be more steady on the rest Disclaimer: Im fully aware of the fact that im not a professional welder

[davo727]

Sorry about the blurry pic but this is the inside upper radius welded up where the crack was.

[davo727]

Heres where the crossways crack was on the upper beam, welded up and ground flat.

[davo727]

Upper plate tacked on. At a stopping point cause its dark and I have to go back to work in the morning.

My friend Bill is taking the dozer and getting a root rake installed on the front by a shop in cleveland tx and in 4 days will bring it back here and I will continue on the welding.

[Swamp rat]

Davo - repair is coming along pretty well , don't forget to wrap the shaft on your Hyd. cylinder - one buckshot will ruin the packing. Good job.

[duaneb55]

Looking good Dave. I commend you on taking the initiative to fix this in return for the use of the machine.