Danger warning!!!

davmor

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Aug 14, 2009
Messages
30
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Location
Coweta,Oklahoma
i was thinkin of havin my trailer made into a break away tongue for extra space in garage not so sure now good warnin though.
 

SmallJaw

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Jun 29, 2012
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Priceville, Alabama
Red, I was just reading about your bolt breaking and looking at the pictures. It makes me shake just thinking about what "could" have happened too. I'm no metal expert but I have done a lot of industrial machine rebuilds and such. I'm curious about a couple of things that that could be behind what happened to your bolt. Of course you did not over tighten the bolt since you never touched it, but it might be a good idea to check the torque on them from time to time. I'd like to know what the best torque would be? 80 lbs? If the bolt were tightened too much it could literally over time stretch the bolt at it's weakest point, causing a break. Another thing I noticed in the pictures you attached is some rust on the bolt shank. Not a whole lot but it looks like to me that the bolt is more of a pivot point than anything else and there would therefore need to be clearance of a few thousands for the pivot to swing properly. The rust could have expanded inside the collar, pinching down on the bolt shank as you turned left and right a zillion times while on the road. If the rust caused the bolts collar opening to get too tightit could have led to the bolt work hardening and finally breaking. Who knows for sure? I've got the same set up on my trailer and I would like to know some answers. I'd hate to lose my baby on the interstate too.:gasp
 

GotMyAlly

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Mar 15, 2005
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Olive Branch, MS
Jim's tongue has a lot of play. You can grab the coupler and move it up and down. My $.02 worth....i think the holes are wallowed out and allow that up and down movement. That probably puts more shock load on the bolts instead of steady clamping pressure.
 

SmallJaw

Active Member
Joined
Jun 29, 2012
Messages
497
Points
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Location
Priceville, Alabama
Jim's tongue has a lot of play. You can grab the coupler and move it up and down. My $.02 worth....i think the holes are wallowed out and allow that up and down movement. That probably puts more shock load on the bolts instead of steady clamping pressure.
When I first read your post the first thought I had was that I know a bunch of people with loose tongues!:gasp But you made your point to quick for me to get too deep picking those folks out.:big grin. I do think the holes are probably wallowed out because the bolts could have been just a few thou small. The vibrations from the ball to tongue can set up action or movement where the bolt touches the tongue wall during changes in speed or direction. That movement in vibration analysis talk is measured in radial movement and the g-forces are pretty drastic given a boat/trailers weight. I've seen this on a couple of my own boat trailers.:wink
 
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