Need some input on repair of a hole in a part I cannot mount on a machine.

Oooh, ooh... before having to resort to cutting off the ears (a move I would choose not to do), I might see if I couldn't make a flanged bushing of some type that I could bolt to the inside or outside of the frame, where ever I could find space (assuming I could).
 
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If you have welding gear, I'd drill the hole oversize, fit a steel bushing in the hole, get everything lined up and then tack or braze the bushing in place.
 
I've run into this situation many times in the field. A large piece of production machinery that has a bearing worn to the point it can no longer function properly. The first task at hand would be to either find a print showing the exact location, or in the case where no print is available find an identical piece, which in your case would be the opposite end of the machine. Measure the undamaged piece from known identical surfaces to find the center of the hole. Then make a fixture that can either be clamped, bolted, or tack welded to the damaged section with an oversize size hole in the proper location. Once the fixture is in place you can use a mag drill with the appropriate size cutter (drill, hole saw, etc.) Align the cutter to make a new hole that will be larger in diameter than the damaged area.

Once you have a large enough hole you can make a bushing with a matching OD and proper ID to fit the shaft. Press it in the existing piece and weld it in place if possible. If space allows you might be able to bolt a flange bearing to the existing damaged piece. In this case however It appears boring and fabricating a bushing would be the most logical choice.
 
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This is not rocket science or surgery.
I doubt that when it was built that it was made to tight tolerances. Do you have any idea how many of these machines are out here worn out and still making good parts?
Dont over think or over engineer this make another ear that is finished use a bar to locate and measure to or from and weld it on.
Then you can get on to more important things.
 
Turn a carbon rod to the size you want the hole to be. Center the turned carbon rod in the part where you want the finished hole to be. You may have to bevel around the hole for the weld to penetrate to the center of the part being repared. Then weld up the missing metal. I normally would use stick arc at a higher than normal heat to have the needed penetration. The weld won't stick to the carbon rod and when the rod is removed there is a hole left where the rod was. I use this process to repair farm equipment draw bars or where the three point hooks up. It leaves a nice slip fit for a new pin to fit in with no machining required. There is no way a 12 foot disc or 10 foot scraper is going to fit in any mill that I have.
 
Nutfarmer said:
Turn a carbon rod to the size you want the hole to be. Center the turned carbon rod in the part where you want the finished hole to be. You may have to bevel around the hole for the weld to penetrate to the center of the part being repared. Then weld up the missing metal. I normally would use stick arc at a higher than normal heat to have the needed penetration. The weld won't stick to the carbon rod and when the rod is removed there is a hole left where the rod was. I use this process to repair farm equipment draw bars or where the three point hooks up. It leaves a nice slip fit for a new pin to fit in with no machining required. There is no way a 12 foot disc or 10 foot scraper is going to fit in any mill that I have.
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@Nutfarmer that is a technique I had never seen nor heard of. I like having that one stored in the back of my head. If it doesn't fall out (of my head) it could come in handy one day.
 
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