Bracing trailer underbelly

[lots2seeinmyrv]

Not sure where to post this. Our Coroplast, stiff plastic, underbelly is sagging in the middle and laying on top of our axles.

How do we go about putting a brace across there, or screwing it back up?

We do not want to accidently put a screw in the holding tank. Do we put the screws directly into the frame? Will this compromise the frame?

Any tips how to tackle this project appreciated.

Thank you.

[lots2seeinmyrv]

Thank you for all the suggestions, much appreciated. Headed to Lowe's to see what they have.

[Huntindog]

You can put a cross brace almost anywhere you need. Just cut a piece of wood... A 1x4 will work fine. Cut it to the length measured between the frame rails. Then tilt it into place. Run your screws thru the coroplast into the wood. This will support the coroplast and hold the wood in place at the same time. This is how a lot of my cross bracing was done from the factory... It has worked well fo 7 years and tens of thousands of miles

[AirSupport]

Double post

[AirSupport]

I welded 2" x 2" x 1/8" angle iron on the frame with some risers that lifted the angle iron up flush to the floor on a friend's trailer. Then again, I ised to be a professional welder with experience with welding trailer frames of all things.

Find a qualified local welder and you'll never have that problem of sagging coroplast again.

[MudChucker]

Get some uni strut and cross from I beam to I beam to hold it up

[D_MAX]

Yup I'd brace as mentioned. Or take a razor blade slice it open and see what's up. Black gorilla tape seals it up like new.

[lots2seeinmyrv]

There is no brace across for about 7 feet of this section forward to back. Only screwed to the sides, not across the middle.

Someone on another forum has the same trailer and just emailed his picture. He has a cross brace 2' forward and 2' aft of his axles so we have a point in which to start feeling for the frame to screw in the brace.

It is definitely not a dropped tank or water. Just too heavy a section that finally warped over time and sagged.

We will get the aluminum strip.

Thanks everyone.

[downtheroad]

That looks an awful lot like one of your holding tanks has broken loose and dropped down, or one of them has leaked and there is a lot of water sitting on top of the Coroplast.
For sure determine why the Coroplast dropped down before you do anything.

Hopefully not.
Good luck with it.

[MFL]

I would not be afraid to use screws in the frame, or cross braces like Wayne mentioned. The screws in mine have large washers to help hold as well.

Thanks for the pic, it shows that it is easy to see behind the coroplast, so obviously no tank dropped, or water damage.

A light piece of angle iron may help hold it up to an existing cross brace. Even an aluminum angle strip may be strong enough. In any case, adding a strip would cut down on the number of screws needed.

Jerry

[lots2seeinmyrv]

It was not fastened with screws...just sagged over time I guess.

We pushed up on it and it is flexible...the tank did not drop onto it. There is no water in it making it bow.

Not being able to see in there...we just want to make sure we hit the frame with the screws...and we will get a metal brace to go across.

Thank you!

[lots2seeinmyrv]

[MFL]

Where was it fastened up to begin with? Mine, and most I've seen are held up with screws in the frame lip.

Can you see the tanks inside, to know that one did not drop down, pushing the coroplast down to the axles.

If all is well with the tanks, I'd run screws along the coroplast edge into the frame edge, keeping it like it originally was.

Without pictures, it is hard to offer opinions.

Jerry

[WayneAt63044]

My coroplast has screws into the cross members of the frame keeping it well above the axles. If adding screws, be sure to look that the area is clear of potential screw damage.