What's This? Monocoque's Pic needs clarification

[Distantdrummer]

Two questions down at the right lower part of pic.

What is the metal piece ? Looks like flashing... is it factory stock?


Are the "Y" channels always overhanging the outer edge of the outriggers as shown? What's the point of that I wonder?


Picture courtesy of Monocoque San Antonio Tx.
75 Overlander

sorry for the small pix, I was trying to enlarge. Have no idea why this is such a task to operate on this forum.
I see some posted pix that are enlargeable. Appparently this one is not.
dd

[Silvertwinkie]

Never tore into one, but it looks like (from inside to out) inside skin, rib, outside skin...bottom is the "C" channel which appears to be connected to rotted plywood. C channel may overhang, I'm not sure.

[Ganaraska]

From other threads... it seems Airstream had 2 different methods of building the trailer.

Old style (60s) was to put the plywood on the frame then install the belly pan with the aluminum wrapped over the edge of the floor. Then they fastened on a U channel all around the edge. Finally they put the body shell on the U channel with the metal of the body overlapping the belly pan.

On newer trailers (80s) they made the floor first, with U channel around the edge. Then set the body shell on the floor. Finally they put the complete body onto the frame.

This accounts for the different ways the layers of wood and metal overlap.

There is a video on You tube that shows the trailers being built at the factory in the early 80s. If you can look it up it is very enlightening as to the way the trailers are put together.

[Torii]

Mine was pretty much identical to that with slightly less over-hang of the Channel. That extra flashing was on mine also - not sure of it's purpose. I simply slid the new plywood in and buttoned things back up the way they were.

Note that it will be more difficult to slide the plywood into the channel than it was to remove. The weight of the shell will close the channel opening slightly and pinch the plywood.

-Torii

[Distantdrummer]

Here is a better picture I hope more viewable.
Again what is the mystery metal in lower right? Looks like flashing.

And why does the "Y" channel overhang the outriggers by what looks like 3/4 of an inch?

[Distantdrummer]

Originally Posted by Torii

Mine was pretty much identical to that with slightly less over-hang of the Channel. That extra flashing was on mine also - not sure of it's purpose. I simply slid the new plywood in and buttoned things back up the way they were.

Note that it will be more difficult to slide the plywood into the channel than it was to remove. The weight of the shell will close the channel opening slightly and pinch the plywood.

-Torii

Torii
I had never heard that about a squeeze or partial collapse of the "Y" channel. That could spell big trouble for insertion of new flooring.
Even if the edge was routed to a slight chamfer it wouldn't slide all the way back into the channel. And there is no feasable way to hold it open either.
Shim spacers would be in the way. Pretty scary.

It actually appears that the open side of the "Y" lower pocket is a bit larger than the back (leg) side. This could be to allow a bit of squeeze closure.
Although I would be surprised if the Airstream "engineers" thought that far ahead of time. Not sure they were concerned with floor replacement 40 years down the line.
I hope you are mistaken, and maybe had a hair thicker plywood.
Plywood thickness dimensions are so confusing and I am not sure micrometer accurate.
Can I assume that mystery flashing is folded back under the bottom of the "Y" channel?
Cannot think of its purpose.

thanks

[Torii]

Originally Posted by Distantdrummer

Shim spacers would be in the way. Pretty scary.

I actually shimmed it temporarily with scrap ply while I prepared the new sheets. It took some finesse to get the new sheets in and get everything the way it was again... Had to bump it from the exterior side once the new sheet was in to get it seated all the way in the channel. It was a bit dicey but it worked out in the end.

Originally Posted by Distantdrummer

Can I assume that mystery flashing is folded back under the bottom of the "Y" channel?

If I remember correctly it does not fold under. It is simple angle stock.

-T

[CanoeStream]

I'm not sure where you are on the trailer. With the bow I assume you aren't on the front or the back. Step back and give us a pic to orient please. At the very front overlying the frame but under the floor is a layer of aluminum in case the owner might later install an optional spare tire under the front of the trailer between the A-frame.

[53flyingcloud]

1.First picture was:
320px × 240px
18.45 kB (18894 bytes)
Not very good for enlargement purpose or viewing added details.
2.The second picture:
640px × 480px
58.24 kB (59634 bytes)
As you saw, much better viewing details.
If you really want to enlarge it, you need to increase the pixel even more.
Good luck on your project~!

[Distantdrummer]

I didn't take the pic. I lifted here on the forums from Monocoque of San Antonio, Tx.
I assume it is his own trailer.
I do not know the orientation. I have wondered how he happened to have a cut-away of the "Y" channel myself. I am hoping he will see this thread and respond. Note the thread's title.
I think it is one of the best representations of the floor/channel/outrigger stack that I have seen.
Keeping in mind that this "Y" channel system only began in the early 70's I believe.
From the pic it doesn't look like the mystery metal is running back across the whole width as to be the spare tire ceiling.
Maybe its an optical illusion. Maybe its part of the banana wrap tho I doubt it. I know I have studied the pic for an hour and I cannot figure it out.

[53flyingcloud]

My first impression was, it's part of the banana wrap.
Without seeing it up close, in person, I can't think of anything else it could be.
I'll be watching for the final answer..