The Trunk

[LFC]

Originally Posted by Wild-Air

As we know, Airstreams are quite limited in external storage capacity. Someplace to put the BBQ grill, somewhere for the folding chairs, and where does the gas for the generator go? And the generator?

With that in mind, I designed a platform to mount an external removable storage trunk. Of course, it had to be aluminum and it had to have a minimal footprint. With those thoughts in mind, and using the two frame-mounted 2" receiver hitches I had installed at George Sutton RV when I bought the trailer, I set out to put this trunk idea together.

After much searching and researching, I found a tool chest that met my needs and then located a local fabricator to build the platform. Once the trunk was mounted, I started throwing stuff in there - a shovel, umbrellas for the chairs, the chairs, the grill, hoses, a power cord, a hydraulic jack, you know - stuff. As you can see from the pictures, it came out just great.

Novel idea....but that's too nice a trailer to screw up.

[Del Gurney]

Russ: Not to high jack your thread here but below is a pic of what I came up with and I'm open to critique as now I'm getting worried..but mostly about bottoming out.
The concept was not so much to add weighty things but double the volume and seal up the storage "Trunk" as it was a bit rusty.
The bumper is now on SST marine grade drawer pull's, the "addition" is a sport fishing rod holder that weighs about the same as the original metal bottom and everything is gasketed and caulked to prevent water getting in.
The storage below does not exceed the depth of the SKID PLATES but should I wonder about the windage down there Folks? Oh the bumper is now held in place with pins through the original bolt holes and rubber strops from below.

[Del Gurney]

Where'd my pic go?
Oh, there it is.

[Wild-Air]

Originally Posted by LFC

Novel idea....but that's too nice a trailer to screw up.

Yeah, and the canvas Da Vinci painted the Mona Lisa on was pretty clean before he got to it, huh?

Reminds me of that nut who thought we needed a light bulb.

[Wild-Air]

Del - That's brilliant! Great design and a clever use of space. Don't let the grumps convince you otherwise - "The Trunk" is working famously over mountain roads, and up and down the interstate. So far, despite the concerns of others, the back end of the trailer hasn't ripped apart nor have the frame rails warped.

It looks like your design will be wonderful. Good job!

[switz]

Actually, I saw that there is a huge frame jig, which could easily handle 35' foot long pieces of skin, which appears to be quite old on the shop floor. It has color coded slots for the ribs depending on the model they are making. After the holes are pre-cut except for an inch of material to hold the "hole" in place for strength while moving the sheet from the cutting table, the outer skin is attached to the ribs before moving to the next station. I will know more in January as I spend the days at the factory watching our unit come to life.

My observation is that all models apparently use the same side ribs and width of side panels. The width factor is controlled by the roof ribs and roof panel.

Since there is a jig for the assembly, it would seem to me that the rib variance might be within a 1/8" to allow for the rib wiggling in it's slot.

[LFC]

Originally Posted by Del Gurney

Where'd my pic go?
Oh, there it is.

Where you tote the poop tube ?

[DoubleNickel]

Originally Posted by Del Gurney

Where'd my pic go?
Oh, there it is.

Del, REALLY nice work, in both design and execution.

Unfortunately, after reading some of snarky comments Russ has received on this thread, it appears that for some here if it wasn't riveted on in Jackson Center, Ohio, it's desecration.

I've been struggling with storage isues on my Airstream and plan to do something similar this winter. I'll post the finished product for the purists with their greasy barbeque grills sliding around under their dinettes to criticize....

[Del Gurney]

LFC: The "stinky slinky" goes in the PVC Tube thats forward (mounted athwart ships) of the grey water tank. I was thinking of adding a second one for fishing rods. That way it's not "contaminating" any water hoses which I'll now keep in the "trunk".

[switz]

It appears that the frame strength would have to increase with the GVW increases associated with the longer models and trim levels. Therefore, would the logic be that the longer or heavier units might better support this trunk design?

[Protagonist]

Originally Posted by switz

It appears that the frame strength would have to increase with the GVW increases associated with the longer models and trim levels. Therefore, would the logic be that the longer or heavier units might better support this trunk design?

Not necessarily. The less overhang you've got, the more likely it is that the trailer can support the load, due to moment of inertia. A bumper-mount box places a load right at the very end of the moment arm where it has the greatest effect. For example, a 75-pound load 10 feet from the axle is the same as a 50-pound load 15 feet from the axle, in terms of bending moment.

And that's just for static (unmoving) loading. When you consider dynamic loading while traveling down the road (when you hit a bump or pothole) a longer trailer has more flex than a shorter trailer due to the longer moment arm, and the load moves through a greater vertical distance, and so applies more force.

A shorter trailer will better support a bumper-mounted load than a longer trailer, all other things being equal.

[nm1oqrz]

The "Trunk" is a beautifully installed addition and as the experts have noted a NO NO.
What I have noticed from this thread is that if it has not damaged the trailer by now then it won't happen at all. I believe that it will take time and I am sure it will happen but not tomorrow. If you search for posts for Rear end seperation there are many pictures and fixes for this problem and these trailers didn't have the load on the bumper but just normal traveling down the road.
JMOO
Happy camping nm1oqrz

[switz]

I did not weigh all the drainage related stuff I put in the factory bumper storage space, but it might be 20 pounds. There was no factory placard providing weight guidance for that storage area. As a matter of fact, I called the factory to inquire into the weight capacity of the overhead storage bins, since that is the major kitchen storage area as well as the major storage area in both ends of the trailer, and that information has never been forthcoming.

On this forum, there has been a lot of information about rear frame separation on more "mature" models and is an on going issue even with the newer versions of the 22' model.

When one looks at the Airstream Catalog, those models less than 25' all have the toilet either right at the back or darn close to it. I lack the detailed knowledge of the shorter trailers construction, but the bomb sight of the 25FB toilet is aimed directly into the black water tank which is just forward of the axles. If a similar ballistic design is in the shorter trailers, then the mass of the black water tank and it's accumulating contents would be at or close to the back of the trailer.

That thought would lend credulence to not putting anything at the back of the coach. Perhaps that is why the two Sport Bambi models lack a rear bumper (including cost savings). That eliminates the leverage that storage area would have on the frame.

And yet, the Eddie Bauer models have a lot of structural beefing at the rear of the trailer to support that door, which is compensated by no permanent low mounted cabinetry in that location. And the "cargo" by default would be at the back of the trailer.

That leaves me wondering if the EB series has a stronger frame to compensate for the rear bias of the loads?

Of interest, while in the UK, I chatted with the local Airstream distributor who explained that they send their frames with flooring from Germany to Jackson Center to have the aluminum shell fitted and then they install the interior when it gets back to the UK. Their pricing, including the 20% VAT, puts the cost of a 27' tandem axle close to Classic levels when considering the exchange rate and the nearly $7,000 frame shipping costs for each unit.

Perhaps the US versions might need a more robust frame redesign since many of our roads are in decline and getting rougher.

[JamuJoe]

Originally Posted by Wild-Air

Del - That's brilliant! Great design and a clever use of space. Don't let the grumps convince you otherwise - "The Trunk" is working famously over mountain roads, and up and down the interstate. So far, despite the concerns of others, the back end of the trailer hasn't ripped apart nor have the frame rails warped.

It looks like your design will be wonderful. Good job!

Wild Air - Thanks for the performance update on the trunk. It's refreshing to see some innovation shared herein.

Del - Great Solution. Kudos for original thinking!

Safe Travels,
JamuJoe

[LFC]

I really don't think anyone including Airstream expects to see damage over night....

As explained the unavoidable damage will happen over time.

[switz]

Perhaps just after the two year warranty expires?

[LFC]

It's his trailer to screw up......

Sad thing is he'll later sell it and we'll read about some other guys woes because of it.

[Protagonist]

The modifications aren't exactly hidden. Anybody buying the trailer later will know what was done and decide for themselves if they want it. These trunks will definitely not be "stupid previous owner tricks," when the trailers are eventually sold.

As long as the mods are not unsafe, unhealthy, or illegal, not a single bleesed one of us has a right to complain about them.

I'm an engineer by profession. And I work on the Operations side of the house, so my whole career has been devoted to making modifications to things to accommodate end-user problems the designers didn't foresee. That means I can't afford to be a purist or I'd be out of a job.

An Airstream trailer is a wonderfully-engineered piece of art, but as it rolls off the assembly line it can't be all things to all people. Del and Russ have developed workable solutions to their storage problems, and Del's is positively elegant. It compromises the function of the rear bumper to resist impacts, but that's a trade-off he's willing to live with. It's not unsafe in that no one will be hurt or killed by it even if an impact does happen; most places don't allow towing with people in the trailer. It's not unhealthy. As long as the trailers still pass mandatory inspections the mods aren't illegal, either.

Even though I see the drawbacks of the two installations, I also applaud Russ and Del for their ingenuity in solving their storage problems. And if the trailers might someday be worth a little less to a second owner because they aren't "pure," they're worth a lot more to the present owners, who will get that much more use out of them.

[Wild-Air]

Originally Posted by LFC

It's his trailer to screw up......

Sad thing is he'll later sell it and we'll read about some other guys woes because of it.

And wouldn't it just be your luck that you were the one who bought it...

[DoubleNickel]

Russ, don't let the naysayers and self-proclaimed Airstream experts get to you. Sounds like a few folks have loose rivets that only the factory trained techs at Jackson Center could fix...

I read through a lot of older threads here on the forum about frame loading. Bottom line is that Airstream hasn't performed finite element analysis on their trailer frames and can't say with any degree of certainty just how strong the frames are for each model configuration. It appears that numerous requests for this information have gone unanswered. The fact that they use the same frame jigs for models with differential loading (rear bath vs/ center for example) bears this out. Without the structural data, fatigue cycles, material specs, manufacturing tolerances, etc,who can really say what the safe load limit is? Certainly not the shoot from the mouth hip crowd taking potshots here.

A lack of outside storage is a problem with AS compared to SOB's. Berating posters who have managed to address a factory shortcoming and making unfounded accusations about their future intent is mean-spirited and counterproductive to the intent of this forum, IMO. I joined this forum to learn about using and improving our AS, but I'm learning a lot more about the people instead...

Despite what others may believe, it's your trailer, use it any way you see fit. I intend to do the same with mine.