U Bolts to Attach Bunk Brackets

[minuteman62-64]

My bunk brackets are currently fastened to the trailer frame with bolts through holes in the cross members. I want to move the brackets slightly in the horizontal direction - but the hole spacing in the cross members won't allow me to position them exactly where I want them.

​Trailer cross members are 3" channel. I've been looking at photos and real life examples of the use of U bolts for fastening the brackets to channel. Most of the real life examples I've seen look like the attached photo (not my trailer - saw it at the launch ramp today). I've also seen photos of the U bolts/brackets in the opposite direction (bracket on flat end of channel and U bolt fed in from open end of channel).

Any pros and cons for either alignment? Any tricks for improving the installation?

Note: just drilling additional holes in the trailer frame is not an option. My days of lying on the ground with drill held over head are long gone - if I can't drill it while standing in front of my drill press, it is not going to get drilled

Again, photo is not my trailer - just an example of U bolt installation similar to what I am thinking of.

 

[Cat nip]

Use u bolts just like in the photo but mount the brackets to the flat side if ay all possible. The brackets usually have nubbens on the mating side to help prevent and unwanted slipping and use the largest diameter washers to help distribute the clamping load of the nuts.

 

[bonz_d]

Nothing wrong with that setup in the picture. A couple of the older Gator trailers I've redone had a curved bracket that fit on the open side of the C channel that the U bolt fit over which helped stabilize the U bolt and prevented it from deforming the frame channel. Never had a problem with those brackets moving or slipping.

The trailer I am using now and will be rebuilding this season has a round tube cross member in the middle and C channel on the end. I need to move the bunks inward also with no bracket mounts available at all. What I'm going to do is try a bracket such as that and fasten it using a muffler clamp type bracket around the tube.

 

[Cat nip]

The muffler clamp idea for round cross member is good. Just try to find the 3/8 diameter ones. They are getting cheap and most of the ones we have been getting at work are now 5/16 and dont seem very strong.

 

[airshot]

Based on your pic I would suggest a solid piece of metal mabey 1/4" material to replace those two washers on the end of the u-bolt. That will create much better clamping power/less slippage, other than that you should be fine. You didn't say how heavy your boat weight might be, so give some consideration to something stronger if your boat is "really" heavy.

 

[minuteman62-64]

Based on your pic I would suggest a solid piece of metal mabey 1/4" material to replace those two washers on the end of the u-bolt. That will create much better clamping power/less slippage, other than that you should be fine. You didn't say how heavy your boat weight might be, so give some consideration to something stronger if your boat is "really" heavy.

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​Boat is a tinny - maybe 800 lbs. fully loaded.

I was thinking of something like those end pieces you see on a lot of the U bolts - only a little heftier. I've got some 1/8" SS bar that might do the trick.

 

[bonz_d]

I looked thru my photo albums and I guess I didn't take of save any pictures of the hardware that was on those Gators. Sure wish I had.