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winchman
02-14-2012, 08:05 AM
I got this project the other day.

http://img.photobucket.com/albums/1003/winchman/MiscellaneousJanuary2012on012.jpg

It was a pretty easy fix to attach the 3/8" plate and match drill the hole for the 7/8" pin. Then I drilled and tapped the pin to for a bolt and washer, so it would be long enough.

http://img.photobucket.com/albums/1003/winchman/MiscellaneousJanuary2012on019.jpg

http://img.photobucket.com/albums/1003/winchman/MiscellaneousJanuary2012on020.jpg

I put the gearbox on the Bridgeport with the output shaft clamped in the vice and shims clamped under the good ear to keep it from rocking.

Davo J
02-14-2012, 09:26 AM
Looks like a good solid fix.

Dave

Black_Moons
02-14-2012, 09:32 AM
Does look like there is more meat around the hole, but the plate is not nearly as thick as the origional cast iron.. Im kinda wondering how exactly that bolt in the pin is gonna hold up.

So, Plus for making the replacement outta steel, Less brittle. Hopefuly that was smashed during an accident, and not during normal operation.
Plus for making the hole further from the edge of the plate, hopefuly that won't cause any interferance issues.

Minus for the pin not going all the way through. And the thinner plate.

Still, Looks like a good job. Nice to see 'no weld' repairs now and then, Since it would take a HUGE welder to work on something like that.

winchman
02-14-2012, 09:48 AM
The pin does extend all the way through the plate, but the hole for the cotter pin was covered. There's no load on the bolt except the tension to hold the washer in place.

One of the cotter pins dropped out while they were using the digger, and the pin worked its way out of the good ear. That put a bending load on the ear that broke.

Black_Moons
02-14-2012, 09:54 AM
The pin does extend all the way through the plate, but the hole for the cotter pin was covered. There's no load on the bolt except the tension to hold the washer in place.

One of the cotter pins dropped out while they were using the digger, and the pin worked its way out of the good ear. That put a bending load on the ear that broke.

Ahhhh ok that explains it. Yea, Good repair then since it was an 'accident' that broke the cast iron in the first place.

Any loctite on the bolt? Or did you just stick the pin in a nice vise and tighten it up super well? Bolts seem to love to come undone on me if I don't do something to stop them.

HWooldridge
02-14-2012, 10:37 AM
The pin does extend all the way through the plate, but the hole for the cotter pin was covered. There's no load on the bolt except the tension to hold the washer in place.

One of the cotter pins dropped out while they were using the digger, and the pin worked its way out of the good ear. That put a bending load on the ear that broke.

That's probably the correct root cause in this case but a lot of people put the wrong bolts in for shear pins and wreck all sorts of farm equipment, including augers. The original design engineers typically figure in shear pins for a reason.

Black_Moons
02-14-2012, 10:55 AM
That's probably the correct root cause in this case but a lot of people put the wrong bolts in for shear pins and wreck all sorts of farm equipment, including augers. The original design engineers typically figure in shear pins for a reason.

cotter pin, Not shear pin. One is designed to snap, The other is not.