The first night we slept in our New-to-Us Southwind, we noticed the mattress seemed to sag in the middle. We flipped the mattress and gave it another try. Still sags.. Maybe we need a new mattress ??
Last winter I was loading the motorhome for our annual trip south. When I raised the bed to store things under the bed, I noticed the bed platform sagged in the middle, REAL BAD. Maybe there wasn’t anything wrong with the mattress, the platform is sagging and needs additional support.
For the next few weeks I thought about how I could add cross supports and / or possibly a support in the middle. I have access to a lot of scrap metal, so I decided to add three angle iron cross members under the hinged platform to prevent it from sagging.
To show how much the platform was sagging, I laid an angle iron support on top of the bed platform. You can see, even with no weight on the bed, it was sagging over 2 inches in the middle.
I cut three 2 x 2 x 1/8 angle irons 60 inches long. Two of these I notched 2 inches from each end. The third I notched 4 inches from each end.
The beds hinged platform is made of two pieces of plywood. When laying in bed, the center of the body weight just happens to be where the two pieces of plywood join together. This is a weak point and greatly contributes to the sagging. I bolted one of the angles on the underside of the platform at this joint. I mounted one support toward the head of the bed where it hinges. This area wasn’t being supported and would bounce. The third support is mounted about 1/2 way between where the plywood seam is and the foot of the bed.
The notches on the end of the angles rest on the frame of the bed when the platform was closed. This helps transfer loads from the angle iron supports directly to the bed frame. The angle iron with the 4 inch notch is mounted so the gas lift spring clears the angle support when the bed platform is closed.
To secure the angles to the underside of the platform, I use three 1-1/4 inch x 1/4 x 20 lag bolts on each angle iron. The three bolts with fender washers go down through the top of the platform, through the angle iron, and secured with a lock washer and nut. The two end holes are about 5 inches in from ends, the third bolt is in the middle. These bolts don’t hold any weight, they just hold the angle to the bottom of the platform when the platform is raised.
We haven’t slept on the bed yet to test it, but I can now stand on it and there is no bending or sagging in the middle. Sleep tight. 🙂
UPDATE – No more sag and the mattress is very comfortable. 🙂 🙂
How did you fasten the steel supports? I’m planning on using tee nuts on the wood frame, and then using countersunk bolts on the underside of the steel framing.
Great site, by the way. It’s been very helpful for my new-to-me 1999 Pace Arrow Vision.
Nothing fancy, regular ole 1/4×20 carriage bolts that go down from the top, through the platform and through the angle iron. Three on each angle support. One on each end and one in the middle.
I did use a large area washer under the head to help spread out the load