# Best way to unbend a trailer frame?



## beorning

I picked up a free utility trailer a while back. The snow finally melted enough that I could get to it and yank all the rotten old plywood off. The frame is homemade. There is a slight bow in the frame from front to back and the tongue is a wee bit crooked. I think it would pull fine, It didn't give me any problems on the way home, but I'm anal.

Is there a simple way to straighten the frame up? Or is it not worth bothering with?


----------



## james dilley

You can get by with cutting A notch into the top if its bowed up in the middle. then rewelding it back. Oh I would also put A plate on each side of the welds and weld them into place.. But make sure you have it level and sitting level. If you know anybody who has A large press they can straiten it .


----------



## farminghandyman

now that the bed is off, if you have a big heavy channel or tubing or some thing, Rail road tie, some thing that is longer than the bed, put two blocks (that are as tall as a good hydraulic jack, on each end of the trailer, over the rail that is bent, place the iron or beam, and chain the ends to the trailer, place some thing to spread out the weight some on the jack, and start to jack the bow down, (my guess is it may take a 20 ton jack unless the trailer is very light, and my guess is it is if it has a ply wood floor,

the other idea is take to a body shop and have them chain it to the floor in the center and jack each end up,


----------



## Up North

beorning you didn't say if the frame is bowed downward or upward. If it is bowed upward, this may be intentional. many trailers are built with some camber, so that when loaded the downbearing weight pushes the trailer frame down to straight.
However if you do wish to straighten it, you can do so by putting timbers under each end of the trailer frame , then apply downward pressure by putting a tractor frontend loader bucket on frame and use weight of tractor to push it back to straight,


----------



## beorning

It's bowed upwards. But it really is pretty slight. Maybe 3/4 of an inch difference between the center and the ends of the frame.The axle is directly under the bow, so I don't think that it was deliberately cambered. The way it's put together, it wouldn't move under weight anyway. The guy who used to own it hauled a riding mower around in it and I'm guessing the weight on the tires of the mower bent the frame on either side of the axle over time. There's really no telling though. The trailer belonged to my buddies grandad, who passed away several years ago. He was an interesting character. No telling what he did with the trailer. 

I'm going to put a new wooden box on it, so I'm thinking I might just lay that out and see if it works out ok before I futz with it. I don't have a tractor or a bottle jack, and I don't have any welding equipment, so I would probably need to take it somewhere to do anything. ( I'll be glad when we move out of town and onto some land so I can justify more tools and equipment to the "accountant") I won't be hauling much weight with it. Probably never over a thousand pounds. I'll be pulling it with a 4-cylinder Tacoma, so I'm kinda limited there anyway. 


It will probably be OK as is, I just like straight lines.

Anyone foresee any problem with the tongue being a little bit out of kilter?


----------



## justmyluk

Here's a trick I used to straighten the tongue on my trailer (friend borrowed it and jacknifed it backing up).

Find two trees tha grew close together or a tree that forks close to the ground. Place the tongue between the trees (or between the fork) and put a chain around the back end of the trailer. Pull the back end of the trailer with your truck or tractor in the opposit direction of the bow.

Works every time...


----------



## GREENCOUNTYPETE

not worth it if it pulls fine


----------



## hunter63

Best way is to hook it up and give it a try, see how it pulls.
As for towing it with a 4 cyl, light vehicle, cafeful on the weight, the 4 cyl may be able to pull it, but you need to keep in mind the extra weight to stop it.

Have used the "chain it to a big tree", as a stop, then "tweaking a tongue" by pulling it with my vehicle the way you want it. Crude but it will work, just be careful.
Body shop, with a frame machine is the best way.


----------



## Junkmanme

If you can locate a section of "abandoned" railroad track, You can use chains and a hydraulic "Porta-Power" tool to straighten the frame. I have done this with a bent pickup frame.


----------



## beorning

Just wanted to give an update r.e.- what worked for the trailer...

The bend in the tongue was fixed by chaining the back end of the trailer to a truck, heating the tongue with a friends torch and bendning it by inserting a 10 foot long length of iron plumping pipe into the tongue and levering it straight. It was incredibly quick and easy. Once the pipe was straight, we reheated it and quenched it in cold water to harden it up again.

I had planned on bolting on a deck of 2x4's laid flat with 3/4 inch ply as a deck surface. The bow in the frame was corrected by using 4x4's instead of 2x4's. The wood, once bolted down, pulled the bow flat ( it was pretty slight) and really stiffened the frame up as well. The deck then went on top of the 4x4's. 

I asked around at ten or so different body shops and none of them would touch the trailer. I found a couple of trailer repair places, but they only worked on large trailers and wouldn't touch a 4x8. I guess business is a little too good for them. 

All told, I ended up with a hoss of a utility trailer for less than $300. Turned out pretty good.


----------

