Extra Elevator Bolts in Replacement Floor?

[phlegm]

I just finished installing a new piece of subfloor in my '71 Sovereign.


And I was wondering if there is any benefit to adding a few more elevator bolts to the outer u-channel that mates the outer skin to the floor board.

Curbside
Maybe one here?




Streetside, the water heater isn't going back in for a while.



Does adding more make the structure too rigid?
Thanks in advance
-ron

[Aerowood]

No reason that you can't. I certainly did.

[rugjenkins]

Another option is to use fender washers with a self tapping hex head screw. They will be inside the walls so you won't see them

[phlegm]

I have the rear banana wraps off so getting at the bottom right now is very easy.

[rugjenkins]

If you have extra bolts go for it[emoji106]

[phlegm]

There are 2 bulk bolt stores in Fargo that carry them.
I can buy as many as I need.

I wasn't certain that with the design of shell holding trailer and trailer holding shell, if it was a good idea or not. There is such a thing as TOO rigid. And I don't need that.

[rugjenkins]

I reconfigured the whole shell/floor/frame connection on mine. I welded a 2 inch perimeter band around the whole frame and stubbed up hold down bars at the ribs. I wanted the floor to be removable without taking the shell off. Adding more connectors is a good thing IMHO. Post some more pics. If your curious I'll post a pic of what I did. The photos are on my other phone

[blickcd]

It looks like you got that plywood installed in one piece. I don't see any seams.

I am currently working on the same area in a 1979 and was trying to figure out my splices. It would be nice to just slide one piece in from the outside in the back, but there is that reinforcing steel angle at the top of the rear cross member...

[phlegm]

I did replace the rear floor section in 1pc


I believe this is the assembly you are talking about.
Aluminum C-channel, steel reinforcement plate, steel c-channel


When I removed this, I didn't have ANY wood pinched between any of it because the wood had all rotted away.


Since this is my first Airstream, I *assumed* that only a fool would put steel directly against aluminum.

When I reassembled the hind end of my airstream, I left out the steel. I have since learned that the steel was stock from the factory.

I still haven't figured out the best fix for this area, I started a thread a while back but so far, no replies.
Rear Access Door Panel Fix -- AirForums.com

I need to replace/repair the aluminum panel beneath the rear access door due to rot and deterioration, and at that time *if* I need to put the steel L-bracket back in, I can do it at that time.

[perryg114]

You need a rear hold down plate. This is the main structural attachment between the shell and frame. Some have replaced the steel with a much thicker sheet of aluminum. That door back there really weakens the structure. Aerowind's trailer might have this door. I am sure whatever he did was good. I expect what you need with the door is something that goes between the vertical stringers on each side of that hatch. These need to be attached to an angle that goes under the bottom edge of the door. A piece of angle laid in the c-channel of the curved sections really helps stiffen it up so you can get a better connection between the shell and frame and so bolts don't pull through. I would also consider not having a plate that goes under the back of the trailer and just make the rear skins like the side skins. I would consider removing that door and putting a solid panel back there. That is the way mine is. What you are trying to do is connect the frame rails to the shell in as rigid a way as possible. The shell holds up the frame and the frame and floor hold the shape of the shell so it does not bulge out as the sides when it is supporting the weight of the frame and the stuff inside the trailer. You need to distribute the load along the c-channel so you don't rip it off the skin or have bolts pull through that thin sheet metal channel. The hold down plate is trying to distribute that load over the back of the trailer. There is also an angle between the frame rails that it attaches to. There were two large bolts that went directly in the frame rails. You end up with the bolts going through the c-channel, floor, hold down plate, then the angle between the frame rails. I added an angle on the top of the c-channel and a couple smaller ones in the curved sections. I don't know how much room you have with the door frame in the way. I expect you are going to have to remove the frame and make a new piece to replace the rotted out piece that the hold down plate was attached to.



Perry

[blickcd]

Whoops! You need to weld that rear cross member back in place and reinstall that hold down angle.

I will be replacing about the same size area of flooring. My plan is to install it in four sections. The rear corners get installed first, tucking first under the side, and then pushing all the way aft.

The third piece will drop in place and then slide sideways into its channel under the wall.

I am hoping the fourth piece will have enough flex to get into the base channel and then drop in flush with the other flooring.

One nutty idea I have is to have the seams that run with the length of the trailer, land on the lengthwise box tubing of the frame. This to limit the number of wooden splice plates I need to install below.

Also, I have a rear bedroom with the rare original full sized bed, the headboard of which faces the street side wall. Therefore rather than having the lengthwise seams down the centerline of the trailer, I plan to have it off-center. This places seams close to the front of the night stands, so walking around the sides of the bed you are on one continuous piece of subfloor.

Perhaps I am overthinking this. I've been know to do that before.

I also have a few questions for Perry: Your angle iron in the base channel, in lieu of fender washers looks like a great idea. Did you do anything to protect against galvanic corrosion or just paint it really well?

Also, I see you had to reinforce your frame rail with that white piece of steel welded in. My frame rail on that side has badly deteriorated just like yours. My plan was to tuck some 2x2 angle up inside there and weld it in place, with a doubler plate on the outboard side of the web. I'd like some more information on your repair job.

Perhaps a link would be best, Perry. I don't want to hijack this thread.

[phlegm]

On my trailer, under the rear access door it was a metal 1"x2"x1" c-channel, not angle iron.

My original cross brace suffered from a bad case of swiss cheese-itus.


I cut it out and welded in a new one.


I used 1.5" flat washers top and bottom on all the bolts under the rear window. The 3/8" bolts at the frame rails and the 5/16" bolts that I used under the access door.

That, and one piece of bolt in 1x1 angle iron that held the black tank, was the only rust in the trailer frame that I've found so far. I coated the whole thing with 'Rust Proof' that I bought at Napa.

Originally Posted by perryg114

You need a rear hold down plate. This is the main structural attachment between the shell and frame. Some have replaced the steel with a much thicker sheet of aluminum. That door back there really weakens the structure. Aerowind's trailer might have this door. I am sure whatever he did was good.

No Door, he replaced the entire center piece of aluminum.
'71 Globetrotter Full Monte -- Page 4

Originally Posted by Aerowood

the one I removed from my Globetrotter ran under the floor and was made of galvanized Steel. It was a bent piece that ran 3 inches fwd between the frame and sub floor. Mine stooped in width just short of the vertical frames. I replaced mine with .063 2024-T3 aluminum. A picture of the one I removed is on #29 of this post.

'71 Globetrotter Full Monte -- Page 3

But no pic of the finished product that I could find.

Mine was trashed and I have no idea what it looked like originally.

Does anybody have a blow up diagram of the order that these parts are supposed to be put together?

I really thought about adding in some additional steel between the outrigger and back tot he main frame rails. My thoughts were that the floor bolts would be attached to the new steel and the wood floor. That way there wouldn't be any connection between the steel frame and the aluminum shell, less chance for galvanic reactions, the outer shell will still be bolted/riveted together like OEM.

[phlegm]

I really don't like the idea of piecing the floor together back there, it seems like that would introduce a lot of moving joints.

A while back, I read a thread or a website, or a post, and the owner replaced his 3/4" rear floor section by laminating (2) 3/8" pieces because they were more flexible and he could bend it enough to slip/slide it into place as 1 pc.

I've been trying to find it again, but after an hour no dice.
I'll keep trying.

[blickcd]

I'd rather get it installed as one piece, but don't think that will be possible. Putting a seam down the length of the trailer when replacing subfloor is common. You just put a wide doubler plate of plywood below the seam, screwed and glued together.

[perryg114]

I put extra steel between floor panels to give each panel support. You want the shell and frame to connect as often as possible. Por 15 is a good insulator and you can use it on aluminum. Hot dip galvanized washers and bolts protect both metals. Not a bad ideal to put some insulator between steel and aluminum. Corrosion rates are low if you don't have water soaked insulation keeping it wet. Lower skin will have more problems with corrosion between steel and aluminun. Paint reduces corrosion.

Perry