ford backhoe boom broken

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check this out guys. any advice again would help. this job will be done with portable equip.one question I need answered---the boss had a plate that wrapped around it. One that went from the top part of the boom then wrapped around the boss, then welded to the bottom section of the boom.(almost like if you took your hand and cupped a bottle)(you can see this in the picture below of the boss) . My question: Would I need to replicate this style of attachment? My approach as of now is to fish plate both sides with 3/8ths by 12" by 18". I will then cut a small half moon in the bottom plate to insert the boss into it and weld it. Then add a bottom and top flange plates and weld them directly to the boss. Hope I was clear enough. Attached Images
Reply:Your idea of putting fishplates on the side tied into the bushing is the way to go.  I've seen it done like what your boss did already and it never works well.  If you really wanted to see that wrap around work, it would probably have to be 3/4" plate.
Reply:lovetoweld -  Not a hard job to repair , prep will be your key to success. Once you have the swing-arms removed and suck in the cylinder completely in , block up the boom and then start .    The top plate needs to be cut off as far back as its broke plus a couple inches to be past the fracture area. Clean-up the boom at the boss and check the lower area where the boss attached as well. To help strengthen the boss - tack the boss back in and then cut a plate and insert into the boom that will tye the boss into the sides as well , tack these together , then remove them and weldtogether, then insert back into the boom and weld the plate completely in- since this will be the last time you can access it.   Cut a piece off plate for the top that will tye in to atleast past center of the top of the boss. Cut two side plates the shape of the front of the boom and come around the boss for the swing arms and also around the broke boss - you should have room for a radius of around 1" clearance around the broke boss , to clear the bucket/attachment, make all the corners rounded with a good size radius to releave stress, and cut either a couple holes or blind slots into the largest area of the plate. This will allow a weld area to help support and tye in the original boom together.   Cut a plate to the same describtion for the bottom of the boss as was done on the top.    Gring good bevels on all weld areas then weld out with 7018.    The plate thickness dont need to overkill - the thickness of the booms original material and maybe a 1/8" thicker if you prefer , the repair will be no stronger than the original booms material.   Once you are finished the boss may shrink the bore size some - if so a brake cylinder hone will work on getting it back to size for the pin.   From the pictures there is no sign of grease anywhere - this type of tear on this boss is normally caused by the pin freezing into the boss and will finally rip it off as happened. Make sure the grease fitting is replaced. Also a good retrofit - if there is room between the boss sides and bucket - install some o-rings on the pin and shim them as tight as possible, this will help keep the grease in the boss.    Keep us up dated.Last edited by Swamp rat; 12-30-2012 at 10:02 AM.
Reply:Thanks for your input everyone. This boom broke due to water laying on the boss inside the boom. One look on the inside sidewalks was key. About and inch high all the way around its thin as paper.  Anyway. Roughly how many hours would u guys estimate. I am thinking 2-3 days on my mobile rig. Thanks Greg
Reply:Looks fun.  I think the time frame sounds reasonable, if you keep at it.  Good luck.Bruce DeLaetHeavy Equipment Mechanic and Welder1948 SA-200 short hood1949 LincWelder 1801963 SA-200 red faceMiller S-32-P