Interior Endcap Re-installation

[DanB]

So I'm finally back to the stage of my repair which allows me to pu the rear interior endcap back on. I've run into a couple of issues I'm hoping some folks might be able to help me with.

For the love of God, what is used to adhere the batt insullation to the aluminum prior to installing the endcap? I've tried double-sided tape, various glue, roofing tar (caulking gun type), and spray foam. Some have worked to a various degree, but none very well. I gotta be missing something?

As I'm putting back the endcap, I'm having great diffuculty lining up existing rivit holes. Some do, a lot don't. But, it really looks like I have it installed correctly. I really don't get much choice. It is centered in the rear window, and equal along the sides.

During my repair, I fixed floor/frame sag of greater than an inch. Is it likely that the geometry of the trailer body changed? Thats's about the only reason I can think of.

Your thoughts?

Thanks

[87MH]

Originally Posted by DanB

As I'm putting back the endcap, I'm having great diffuculty lining up existing rivit holes. Some do, a lot don't. But, it really looks like I have it installed correctly....During my repair, I fixed floor/frame sag of greater than an inch. Is it likely that the geometry of the trailer body changed? Thats's about the only reason I can think of.

Absolutely, it is likely that the geometry changed...

Do you have a bunch of cleco's?

I would try to cleco those holes that line up, and have a helper to try to "massage" the walls from the outside to attempt to get a couple of more to line up.

Luck, and pictures, please.

[modarch]

Dan- Home Depot or your preferred DIY superstore has a spray adhesive in a small aerosol can that is made by 3M. I used that to adhere the insulation to the walls and it worked great. Wear a respirator or your nostrils will stick together...

[InsideOut]

Originally Posted by 87MH

Absolutely, it is likely that the geometry changed...

I concur. We had a similar problem a couple of weeks ago ~

It's a Girl!!! - Check out Post #340

Kinda like throwing a pebble in a pond, changing the floor has a ripple effect. Gary's right - get out the cleos!

Shari

[utee94]

My interior skins are going back in this weekend after 4 months out and a floor replacement, so for the holes that DON'T line up, what is your preferred method of attachment? Do you just drill new holes that are away from the old ones, so as not to weaken the structure too much? Does this end up swiss-cheesifying your ribs and runners?

[DanB]

I kinda wondered the same thing, not neccesarily with the rivets, but with the new floor mounts.

Sometimes I think we need a wakeup call about over-engineering. I probably put in enough fasteners to get passed a military specification.

One of "improvements" was for my tail lights. Since I had the back open, I decided to remove them and modify them to be screwed on instead of blind rivets. This way, I can work on them without opening up the interior. I also ran an empty conduit down to the trunk in case I ever need to pull new wires.

[InsideOut]

Originally Posted by utee94

My interior skins are going back in this weekend after 4 months out and a floor replacement, so for the holes that DON'T line up, what is your preferred method of attachment? Do you just drill new holes that are away from the old ones, so as not to weaken the structure too much? Does this end up swiss-cheesifying your ribs and runners?

If you are putting the same panels back in or new panels with holes placed from the old panels using the overlay method, 99% of the holes should line up. Ours did, which is why I was so shocked the overall shape changed enough that we could re-use our interior wood panels. Typically, I wouldn't expect that "some line up and some don't", the aluminum is rigid, not really flexible enough for that. Either they will line up or not - unless it's plastic endcaps you are working with, which could be more flexible. A bit of finessing may be required because ribs may have "sprung out of place" while lose, but they should be able to be put back in place with a few choice words, an extra set of hands and lots of clecos. If one or two don't line up, no big deal just drill them out. If it's a totally new panel with new holes, shift them so they miss the old holes - but I would definately try to use the old ones.

The way we did it with new panels was:
1. drill out the old rivets using an 1/8" drillbit
2. drill the new holes on the new panel(s) with an 1/8" drillbit using the old panel as a template
3. cleo everything in place on the trailer with 1/8" clecos
4. take out every other cleco
5. drill the empty holes in place with 5/32" drillbit through the panel(s) & rib/c-channel
6. buck (or pull Olympics depending on the project) those rivets starting from the center of the panel and work out w/ 5/32" rivets
7. take out the remaining clecos
8. repeat #5-7

If you are re-using your old panels, it should be the same except skip #2.

Hopes that helps ~

Shari

[utee94]

Thanks Shari, it definitely helps. The outer skins are okay, I've left most of that intact and only put in new bellypan material and a new water heater patch, both of which I was able to buck in place while the interior skins are out.

For the interior skins, I'll be re-using the existing ones, since they were in pretty good shape. A little bit of corrosion along the bottoms of a couple of them, but not enough to affect the structural integrity. But I'm expecting that things have shifted enough during frame rot replacement and floor replacement that not all of my old holes will line up. If I can massage them into place such that everything actually lines up, then I'll be delighted!

We'll find out tomorrow.

Dan-- Yes, I probably put in double the required fasteners when I replaced the floor, but I figured I might as well while I was down there, you know?

-Marcus

[markdoane]

Good instructions, Shari.

I might suggest if your endcap is fiberglass, the holes in the fiberglass might be a bit ragged, either due to age, or just the deformation that occurs when the original rivets were set. I upsized the pop rivets on the endcap to 5/32" (hard to find, try Home Depot) to get more bite into good fiberglass.

[Distantdrummer]

Yes Shari excellent and concise instructions to replace interior wall panels.
Unfortunately this gem will be hard for future surfers/searchers to come across since the thread title refers to interior end-cap re-installation.
A whole lot more wall panels will and have been removed than will end caps ever be.
You being a former mod I know you get my drift. I think the only way to fix this is to re-name the thread to include wall re-installation and end cap re-installation.

Now Inland Andy has warned for years about seriously blocking the trailer before removing panels (int.wall,ceiling,roof, end caps int & ext.). Did you all do this and still experience the shifting?

thanks

[DanB]

Blocking mine would not have helped! I jacked up one side substaintially to get it back to "original". I suspect it has been sagging for a couple of decades

[utee94]

My floor was rotted out decades ago and the shell and rubrail were sitting directly on the main frame rails at the back of the coach. The rub-rail was crushed in those two areas, but fortunately the shell was not affected too much.

[Over59]

Putting the front end cap in was the most frustrating of the whole rebuild. It's still not right and I'll be making "adjustments". First this is a three person job. Second you need cleco's. Third use bubble foil as compressing 4 inch glass adds another whole dimension to "fit". Fourth be ready to push real hard. Fifth, start in the middle over the window and work out from there. Yes, the shape of the shell changes when you take the inside panels out or end cap off.

[VIKING]

That 4" fiberglass must have made it almost impossible to get it in. The original was only 1-1/2 or 2". When you compress fiberglass insulation it also affects the r-value negatively from what I've heard.

I'll be getting into all of this very soon now, myself. Thanks for the info!
Rich

[markdoane]

I had to push mine in fairly forcefully to get the holes lined up. I had added an electrical box dead center of the end cap, and judging by how much of the box was bulging, the distance between the outside shell and the inside cap may be as little as 1 inch.

It will depend on how hard the guy was pushing who did the original installation.