outlandish restomod planned

[swhite832]

So, about six months ago I purchase a basket case, 79 tradewind. It is trashed. The frame is broken in the rear and My wife will only "look" inside it. She won't enter it. It needs a shell off restoration.

These are the plans;

Rebuild and extend the frame four feet to the rear to accomodate golf cart, generator etc.
Incorporate receiver hitches all around the frame to accept a removable elevated platform above the trailer...possibly protrding thru the skin.
New, enlarged, holding tanks, hopefully in the same locations the original ones used to be located.
Completely redone bathroom. In the rear.
2 twin bunks center
Minimal kitchen, cook top, micro, fridge.
Some sort of fold out couch/queen bed in front.
Storage wherever possible.
All new custom led lighting in/out

My question is what are the axles rated at and what is the tongue weight in relation to the weight over the axles?

[elolson]

Given your plans and then reading your question leads me to believe that you might be a bit in over your head.


Forget the existing axle ratings. Go build up some autocad or pro-e drawings and start working on your weight and CG with loaded rig considering your mods to make sure tongue weight, and the new axles you will have to fit and offset and going to work right with that extended aft frame and a golf cart. Torque = Length * Force. All that weight in the back will be tough to compensate for up front on your hitch.

[craftsman]

This isn't intended to be negative but your pockets better be deep and and you better have a lot of free time. By the time you finish a project like that, and a lot of people never realize how over their heads they are until it's to late, you could have bought a good used Airstream and been camping. I also assume your a good carpenter, cabinetmaker, sheet metal worker, plumber and electrician. Whatever you estimate it's going to cost, triple your estimate for both time and money. Unless you have an Airstream that's already in pretty good shape, something unusual or money just doesn't matter, restoring a "basket case" is usually a losing proposition.

[byamcaravanner]

Originally Posted by swhite832

Rebuild and extend the frame four feet to the rear to accomodate golf cart, generator etc.

The structural scheme of an Airstream trailer would not allow for this. A traditional box type trailer can be designed to accomodate this type of arrangement but an Airstream is a different bird all together.

[swhite832]

I agree the existing frame would not accomodate such a plan and I don't think that I would "cut up" an Airstream that was already acceptable for camping.

I think the best plan would be to use the existing frame as a template to build one that would accept the shell and have an extended(5ft) section. At first i thought a removable rear section, much like a receiver hitch basket, was the way to go but the more I think about it an integrated rear section is the better avenue due to weight distribution issues. Moving the axles to the rear a predetermined distance would compensate for the added rear weight, keeping the weight ratios in check. I could also "flat bed" the shell on an existing gooseneck but I think that would be just as much work, would not look good, and be more total weight than is neccessary. In essence, I would be utilizing the shell/ interior skin, etc. on a new, stronger, modified, frame that would still accept the shell as designed. The removable rack above would be more of an exoskeleton. The shell would not bear any more weight that it is not already bearing. Starting from the ground up, from scratch, or with a cargo box would be easier no doubt but it wouldn't be an Airstream. The fact that the elevated rack would be removable gives me the flexibilty to utilize this trailer for many different types of events and still retain the Airstream mystique and pull qualities when the rack is not being utilized(regular camping). I wish I could draw you a picture and download it.

I would not consider myself a GOOD plumber, electrician, welder, sheetmetal worker, carpenter, auto mechanic, or interior designer. But, I would call myself adequate in all but sheet metal and I have a resource called airforums.com for that. Over my head?! Obsolutely! No delusions there. Comfort zones are for playtime.

When I finish my shop and master bath(3-6 mo) I will start this project. Thinking about it, planning, and bouncing ideas off others who are familiar with the media for a period of time usually results in a better outcome. I believe I am capable but I do want, need, encourage and crave feedback. It is a very important aspect of any project, especially one that is not of the ordinary variety. I need help from those who have been there. Thank you for replies thus far. I will try to upload some kind of drawing in an attempt to explain my ideas better.

[Goin camping]

As I'm sure you know. Airstreams are designed with the shell and the frame supporting each other. I think it'd called monoquac or somthing like that.

Consider starting with a new longer frame and mount the shell on a mini frame that is then mounted to and isolated from your new longer frame.

You should know I never let my lack of knowledge of engineering get in my way.

Do what makes you happy and chase your dreams.

[Wabbiteer]

To get a monsterously long flat bed trailer (car hauler?) and modify it to accept the aluminum shell might be your best bet - something absolutely ridgid in its own right then narrow its' chassis to match the AS floor foot print, chopping off frame and axles to suit and then a lot of lightening by blending in the stamped spar and plywood flooring...

The folks are not steering you wrong - even rough roads and full tanks are a challange to older Airstreams...

[swhite832]

Let me see if I read you right...repair the original frame, remount shell to original frame, remove axles(dispose), buy two 7000# axles, attached to two I- beams and cross members(car hauler design)etc. Then mount the repaired frame to the I- beams. Work off the I-beams for extraneous, red-neck like racks and platforms? Any ideas how you would attach one frame to the other? A hard attachement or something a little more...forgiving?

Seems like less new metal...I like the idea. It is not much different than what I was thinking of, just a different approach. My plan would have set the I-beams inside the the original frame instead of underneath it. Underneath would give more holding tank room...alot more. So, no banana wrap or belly sheeting? I was trying to keep the banana wrap.

I knew there would be an engineer type lurking around. I love you guys. I am sure if there weren't any problems on this earth you would create some so you could solve them. Hope to here from you again.

Thanks....and "no worries"
sTw

[bake315]

I like the idea of mating the original shell to an existing, extra-long car hauler type trailer. I would consider maybe setting it up so that the "toys" are forward of the axles and allow the shell to sit over and behind the axles. Then I would configure the interior so that the bulk of the weight from appliances, tanks, etc is in the front part of the shell.

It's kinda fun to imagine the possibilities for a trailer that might otherwise be beyond rehabilitation. It'd still be in use and on the road, even as a "one-off".

[elolson]

I stand by my comments. You need to make some drawings and do rough weight and CG calculations. Moving out without a basic plan for a highly customized travel trailer with excessive weight will endanger the public, not to mention yourselves.

Include loaded and empty tanks, and effects of force on the hitch point. Here is a reference to a book online that will help you get started with a real design. Simulation will save a lot of money and maintain safety as will some simple calculations.
motor vehicle dynamics: Modeling and ... - Google Book Search

I apologize for picking on your post, it was late, I was tired and I still think you are in over your head.

Sr. Princ. Systems Engineer.

[swhite832]

Glad to have you on board...expertise in this field is exactly what I was looking for. I will look at the book more in depth in the next few weeks. I hope it is ok that I pick your brain on the stuff that is "over my head". Like I said "no delusions there."

In your opinion, if I added 300 lbs. to approximately 5ft. past the original configuration/weight of a 1979 Tradewind, what size I-beam(s) would you use, from tongue to taillight, assuming all other weight being equal to original configuration? Also, if you were adding five additional cantilevered feet weighing an additional 300 lbs. to a 1979 Tradewind how far back would you move the axles to compensate for load distribution?

I want to be as safe as the next hunk a junk being driven/pulled/dragged down the road. You might as well help. I promise NOT to hold you liable(print it).

[ROBERTSUNRUS]

Hi, swhite832. Nothing is impossible. Right now the frame and body of an Airstream hold each other together. So instead of a 5" high frame you would need a 10" high frame to be able to support itself and the body without flexing concerns. Now for the golf cart extension; With a 10" frame, it should be strong enough, but now you have to deal with tongue weight. To do this you need to relocate the axles one or two feet back to a point that will give you 10-15% tongue weight. If you plan to do this and go with and without the golf cart you would then need to have moveable axles like used on some big rig trailers. Light load [sans golf cart] axle in forward position. Heavy load [with golf cart] axles returned to rearward position. Now you have to find out how much was increased in GVWR and buy axles made to support the new revised weight. Finally you will need to take this trailer to DMV to get it recertified for the new weight rating and title it as a new reconstuction. [protect you legally, for liability] Imposssible, No. Practical, No. Is it your dream to build something that no-one has ever done successfully, Yes? If you have the time, money, and the resources to do it, go for it. Write stories and post pictures; All the critics will be here watching.

[bredlo]

I like the car hauler idea as well, if only for that DMV certification. It'd be a major bummer to go through all that work only to have some grumpy ole' lady named Edna peer over her librarian glasses and stamp REJECTED on your application.

Seems like you'd need to make up for the fact that the body would no longer have that "monocoque" frame mated to it, probably through stiffening it on its own. Obviously the car hauler frame would be plenty strong to start with. All your running gear, clearance heights and engineering of the structural integrity has been done for you.

So.. I guess if this were my baby I'd plan it as two separate projects - the naked frame that's balanced for the generator/golf cart, and then adapting a body to sit on it. Belly pans, etc. would be for show and you can adapt that way later in the process, I'd think.

There's only one major thing left to plan for then: no ordinary golf cart is going to look cool enough to deserve to ride on this thing.

You'll have to budget in a custom aluminum, riveted "Airstream" golf cart. Ooh, Im' already thinking about that one - little clearance lights arched over the roof, baby moon hubcaps and little red numbers that match the big trailer.

[Silvertwinkie]

If you are going to do this, have you just considered buying a longer trailer and doing some heavy mods that way?

I do recall the factory showing at an RV trade show a concept of a garage in the back of an Airstream. This was done by the factory and very recently. I am sure they would provide you some direction on what they did. I do not think their garage concept unit held a car, but it's a step I had never seen Airstream take. Somewhere on this forum are pictures of it. I think it was at the Lousiville show the year before last. If anyone could find that link and post it, I am sure it would be of some use to you.

My thought is, why get one that is too short, get the longer one and do major upgrades to it, rather than weld pig iron together, you can in fact have one solid piece of frame with additional supports.

Keep in mind, I have no idea how of if this would work, but since the factory did it recently, I am sure it can be done. The quesiton is how much time and $$$ do you want to throw at it. Nearly any dream is possible with time and $$$.

[swhite832]

What if the cart location were designed to go in front of the trailer. Obviously, adding to tongue weight. As long as i do not exceed the rated weight of the tow vehicles bumber set up. The additional weight of a golf cart and two five foot sections of of 10" I-beam does not seem excessive to me. Is the belly skin for aerodynamics or is it there to keep moisture and road debris off the under carraige?

Is 10-15% tongue weight a good number? If that is the standard then moving the axles to a location where the the golf cart on or off would not change the tongue weight more than 5%.

Perhaps some "hot shot" folks who haul various types of loads consistantly could weigh in(pun intended).

It isn't practical...and I am over my head, I agree.

I could go buy a toy hauler, box on wheels, with all the latest and greatest features. But, where is the fun in that? I would still have to add a rack over the top.

All valid points that need addressing, I appreciate it. Any others??

[bredlo]

Originally Posted by swhite832

All valid points that need addressing, I appreciate it. Any others??

Yeah, back to my aluminum golf cart idea.
You'd call it the Golfstream, and it'd look like this:

[swhite832]

Duuude...creative thinking has just come to a new level. Does it have A/C?

[elolson]

Originally Posted by swhite832

In your opinion, if I added 300 lbs. to approximately 5ft. past the original configuration/weight of a 1979 Tradewind, what size I-beam(s) would you use, from tongue to taillight, assuming all other weight being equal to original configuration? Also, if you were adding five additional cantilevered feet weighing an additional 300 lbs. to a 1979 Tradewind how far back would you move the axles to compensate for load distribution?

Come on now, Crawl first, walk later. Looking back at your first post and seeing some of the follow on, lets go back to basics so we can get you some real answers. I do not own a tradewind. So lets start with that.

1) Provide the GVWR, should be on a tag somewhere, I am guessing 4000lbs but why guess.
2) Give me some basic measurements. Tip of tongue to front edge of shell. Tip of tongue to first axle. Spacing between axles. Length from center of rear axle to back bumper.
3) Did you have a rough idea of the weight of your golf cart? 300lbs sounds too light.
4) Serious about the extra tank size?

I'll walk you though the basic calculations and show you how to do what if's for where you want to place a golf cart. Other post on the frame design pretty much say that you are going to be bulding a custom frame. 1979, nastran and mechanica were at best in their infancy on some mainframe, probably just first order calculations in those days. A good thing, means the design will be better and stronger, more tolerant of whole sale chucking of the frame and bolting on a different one.

Nothing wrong with public review of calculations. A peer review is your friend, a little scrutiny is a good thing. So basic calcualtions first, gives you an idea of feasibility and what you are up against.

Never claimed to be a structural engineer so not an expert in frame design, but basics are basics and can take you a long way. Throw in a decent safety factor and lots of problems with optimized designs are not as big a deal.

[ebair]

With the appropriate modifications for scale of the current housing unit, please reference the following CAD rendering included for consideration and further structural analysis.
Addition of quadruple outboard removable rotational supports could allow for amphibious operation with retention of current aqueous propulsion device.

[swhite832]

Ebair,
Don't tempt me...like elolson said crawl first.

Elolson,
You are absolutely correct. I will get those measurements, so there is something to work with. I do not own the golf cart yet, but I always build with the future in mind.
GVWR 5800
GAWR 2600? (I'll look again)

How do the designers who engineered the toy haulers currently on the market determine what kind of weight will or will not be in their respective trailers? There is a big difference between the weight of one Harley vs. two. Or, ATVs vs. bicycles. They couldn't possibly know what the purchaser is going to load in that space, yet there doesn't seem to be an issue with pulling those rigs empty vs. loaded