Roof sag fix idea

[DanielM]

So let me preface this by saying I’m cheap, kinda McGyverish and have lots of fab materials in my shop. This is my idea for the fix at sag in roof of front section behind AC unit.
I’m going to use exoskeleton idea from earlier post.
1. Remove all trim to do regular bag seal fix and pull staples.
2. Check condition of wood top bow and sides pieces. What was TM thinking?
3. If crap replace wood, if not multiple coats of epoxy.
3.Make template of crown on rear section of roof where they meet when closed.
4. I have 3 bed frame rails. One for the top section which I’ll bend to match crown. The other two for the side. The wider section of frames will be on top and sides, notched where necessary.(Ac, hold down clamps, awning) I’ll cut narrow side of frame to match inner side of wood. I’ll also cut a piece of 1/16” for underside of top section that has a flap an inch or to bent down the sides to tie in sides.
5. I’ll temporarily place top piece and underside and using “c” clamps draw roof up SLOWLY. Probably going to slowly jack up AC unit as well
6. After seeing how much sag I can take out, I’ll adjust curve of top rail.
7.Test fit then weld top/sides together. Test fit again. Drill holes for screws going into sides and thru bolts at top. Paint and install thin neoprene or rubber strip as isolator between steel and aluminum.
8. Install. Steel frames will become corner and top molding, so seal as necessary
9.As I’m installing, place continuous pvc bendable bolt rope/keeder rail under back flange.
10.Sew new bag seal of appropriate thickness with bolt rope, to feed into keeder track. Install. This should make future replacement easy.
11. Fab new small trim pieces as necessary.

I considered aluminum, but I think steel will be stronger and add only 20# more
Should also stiffen up side walls, perhaps, once dialed in, make raising/lowering easier.
So I’m looking for some feedback and ideas. If this works, it could be a way to solve a problem that quite a few owners of older TM’s have without looking to janky
Thanks for taking the time to consider this.
Daniel

[Bill]

Daniel -

I commented about wall splay in your other thread. (I may combine the two threads so we don't have to jump back and forth.) One step in your plan might be to measure the wall separation at floor level, and again at ceiling level. They should be equal when you are done. If the walls in the front shell are splayed, there will be a gap between the wall of the rear shell and the wall of the front shell. When the trailer is down for travel, this gap can admit road dust and dirt to the inside. When the trailer is up for camping, the gap can admit cold air. Bad on both counts.

Bill

[DanielM]

Bill
Thanks for the tip. Definitely a crucial measurement. I’ve always wondered about the shear on the sidewalls. (Flopping around a bit) Any other thoughts about my plan. I’m not looking for perfection, just an improvement in functionality. It just seems crazy that TM would put a 100 lb ac unit in that spot without some extra structural support. I know weight is always a consideration, but…do you know if there are any beams in the roof or is it more akin to unibody. 40lbs total of aluminum beams @say 4’ o.c. might have been helpful
The reason I split threads is sometimes people don’t revisit past threads and I wanted the input of those that responded to original post.
Daniel

[Bill]

Originally Posted by DanielM

The reason I split threads is sometimes people don’t revisit past threads and I wanted the input of those that responded to original post.

Daniel -

I understand. But as you will find with experience, posts to this Forum are "threaded". This means that there is one topic per thread (generally the thread title), all posts in a thread appear in order of posting, and posts on different topics do not appear in that thread. And when there is a new post in a given thread, the name of the thread is shown in BOLD to signify something new. So if anyone is interested in your roof-sag problem, for instance, they will find all of the posts on that topic in the original thread. No need for you to post in a different thread. And if someone is not interested, he/she simply skips over the entire thread, and doesn't have to wade through irrelevant posts in some other thread.

The Forum is not organized like Facebook, where all posts seem to be shown in whatever order they were received, mixed in with all the others, and there is little if any connection to past posts on the same topic.

Bill

[Dodge trucker]

I have the opposite issue, my rear shell is sagged and is the one with the AC.