Reinforcing trailer I beam frame

[yanmars]

I have a trailer I carry my tractor on. It has a junior light I Beam on both sides. 2 1/4 inch flange, 8 inches high but only about 1/8 inch thick. An old mobile home frame from the 50s. Not rusted. The tractor is a cab MFWD 45 HP Mahindra 4510 with a Bush hog brand heavy 6 foot rotary mower. Front end loader also.
Recently I had about 600 pounds of weight in the pick up bed and when I went unload the tractor the frame buckled midway in the length, kind of between the tires on the right side. Welding shop had a frame straightening devise and with some heat got the buckle out. Really can't see or feel it but concerned if it is weakened. No plates were added to the area.
I did not have any blocks under the rear of the trailer, do not do it all the time, probably should have.
Question. I have many thin steel plates about 7x10 inches about 1/16 in thick. I could drill a series of 1/4 inch holes, 4 say per plate and add 4 on each side of the I beam in the damaged area. I would place them up high against the flange. That would add 1/4 inch of steel on each side of the I beam or about 1/2 inch thickness per side.
Wondering if that would help at all or the holes in the I beam compromise the beam more or would it even be worth the effort? Medium grade bolts although I could get grade 8s.
Thoughts or just leave if alone. I do not think I would have damaged the frame had I not had that extra weight in the pick up bed. I have loaded the tractor combo many times before without issue but the pick up bed was empty those times. Thanks

 

[bcp]

I would sell it as a light duty trailer and buy a proper tractor hauler. I think MH-RV frames get much of their stiffness from the house structure. The bare MH frames I've been around seemed very flimsy and flexible.

Bruce

 

[4570Man]

Mobile home frames have about the same structural integrity as a wet noodle. Sell it and buy a proper trailer.

 

[nisaacs]

How did weight in the pickup bed cause the trailer frame to bend?

 

[sandman2234]

How did weight in the pickup bed cause the trailer frame to bend?

I am with you on this one...inquiring minds want to know!
I think the weight "may" have affected the stress point of the trailer by not allowing it to go up as the tractor came forward. Now that it has been wrinkled and straightened, it is definitely not going to do the work it did before being wrinkled and straightened. That is simple metallurgy.
Drilling and adding plates may help, but I would seriously consider also adding a full length member to the entire length of the trailer.
I re-purposed a 65' mobile home into a 40' trailer to haul a 40' container. After the move, I re-purposed it into a 20' trailer to haul a small dozer. I always kept all the steel from each modification in the trailer. The 20' model had four I-beams running the length of the trailer!
I also have a 5x8 single axle trailer that the frame is 3x3 angle, that I wanted to haul "more" with. I added two 3x3 angles below the frame the whole length of the trailer to add to its strength. Amazing what the did to strengthen the trailer.
David from jax

 

[Yander]

How did weight in the pickup bed cause the trailer frame to bend?

Just a guess, with the extra weight in the pickup it didn't raise the truck as he is pulling on/off the back end of the trailer. Where normally the truck would raise from the weight, and so the trailer took the full force (not being rigid enough it flexed) instead of the pickup.

Again, speculating. I started blocking the back end of my trailer with jacks or 4x4s so it wouldn't lift my truck.

 

[yanmars]

I did not have the back end of the trailer blocked and when the tractor is loaded or unloaded it lifts the back end of the pick up truck off the ground. I think with the added weight there near the trailer tongue the leverage caused it to buckle. That is what I think.

 

[JPRambo]

Is there room to build low walls/trusses/stiffeners around the top of the trailer? (The original mobile home had walls to strengthen the frame).

 

[sandman2234]

Is there room to build low walls/trusses/stiffeners around the top of the trailer? (The original mobile home had walls to strengthen the frame).

Sides welded on twelve to fourteen inches above the existing floor would help, but since the existing frame has already been compromised, I worry about it taking the full weight of the capacity of the trailer before it was compromised. Can it be done, yes, but I would make sure the person doing it was a good welder with a little bit of understanding where stresses are and how they can be offset.
What is the weight of your tractor? I am picturing this with my own tractors, which put a strain on a 14K trailer when I go places, so if your loading a 1500 pound tractor, it won't take quite as much as it would with mine.
David from jax

 

[sandman2234]

I did not have the back end of the trailer blocked and when the tractor is loaded or unloaded it lifts the back end of the pick up truck off the ground. I think with the added weight there near the trailer tongue the leverage caused it to buckle. That is what I think.

If previously you had been blocking it, and this time didn't, it would completely explain the damage. The blocks under the rear supported the weight of the tractor until it got past the axle, thereby allowing for a more controlled distribution of weight. Another good thing to say about blocking the rear of a trailer besides keeping the tow vehicle rear wheels on the ground. Not a bad thing to do, blocking the rear of a trailer when loading! I don't do it, because my ramps have built-in blocks.
David from jax

 

[jaxs]

Don't drill holes in frame. I recommend 3'x10"x1/4" plate tack welded to flange lips. 10" allows plate to extend above or below beam. Before positioning 10" plate onto beam tack weld a 3'x2"x1/4" plate in tee fashion on one edge of 10" plate. Welding lips minimizes effect of welding heat on Jr beam and 2" plate reinforces 10" against twisting. Needless to say,do the same on both beams. If you are determined to use all those 7"x10" pieces and have a stick welder I suppose you could stager and plug weld them together so they form 1/4" plate but imo it's penny wise and pound foolish.

 

[hiddentacocatneddih]

What size axles does it have ? It's probably not worth messing with.

 

[yanmars]

I think the tractor, loader and mower would be around 6000 pounds. The trailer itself is around a ton.

 

[yanmars]

The weld shop did a nice job of removing the buckle. I did bring it back in to add some steel plate in the axle area. I am on the look out for a different trailer however.
My brother got a steel decked 20 foot trailer that he can drive on without separate ramps for $2500 used some years ago. Wish I could find a deal like that on an equipment trailer. His is not a car trailer.

 

[Renze]

Welding or bolting doesnt make much different.

Nonetheless, in bending you have compression in one flange and tension in the other. Adding steel to the web adds little in bending. I would weld flat bar to both the upper and the lower flange where it matters most. Did it on my front loader and on my dump trailer, to use a truck bed subframe as trailer frame.

 

[yanmars]

Got the trailer back, straightened the buckle and added steel welded plate. It appears 1/4 inchx6 1/2 inches by 110 inches long, one on each side. About $1600 but at least the trailer has some use now.
It will work until I can find something heavier, I have my brothers trailer to use in a pinch.