Frame extension

[joeybravo]

Id like to add two ft to the rear of my trailer frame, this is the time to do it, what issue would there be aside from weight distribution?

[ROBERT CROSS]

Extension for storage?
The trailer was designed for that length and axle placement. Without moving the axles, I would do some serious investigation before proceeding.🤓

Sometimes it's not so much the weight, but how the weight bounces.

Good Luck..
Bob
🇺🇸

[Mollysdad]

Originally Posted by ROBERT CROSS

I would do some serious investigation before proceeding.��Sometimes it's not so much the weight, but how the weight bounces.

You're exactly right.
All the interest in the LV caused me to revisit the Living Vehicle demos on YouTube.
They have one on the rear receiver, and Mathew Hoffman discusses that exact thing.

https://www.youtube.com/watch?v=xM-9fxQJvXg

[A W Warn]

Originally Posted by joeybravo

Id like to add two ft to the rear of my trailer frame, this is the time to do it, what issue would there be aside from weight distribution?

IMO, it is more important that extra length and weight behind the axles will enhance the trailer's tendency to sway uncontrollably at high towing speed. Loss of control is dangerous to people.

The bounce of the load extended at the rear can be damaging to the trailer and the items being carried, but probably not so harmful to people.

This article offers some good information>
https://www.trailer-bodybuilders.com...ailer-dynamics

Copied and pasted from the above article>
“Too much trailer inertia can cause trailers to sway,” he said. “It means that with the center-of-gravity location, the weight is too far behind the hitch ball. That means that as you move the center of gravity farther and farther away from the hitch ball, the trailer has more swing inertia. That grows very rapidly. Tire forces are scrubbing to resist sway. As you move the center of gravity, the trailer tire forces really don’t change much. So your resisting forces are essentially constant, but your inertial forces are growing very rapidly as your moment of inertia increases due to the CG being moved rearward.”

[Belegedhel]

Do a search for "bumper storage" and you should find several threads arguing the merits and pitfalls of storing stuff on the rear bumper.

The pitfalls generally boil down to the distribution of weight, and the reality that these trailers are already prone to rear-end separation, so putting more weight hanging off the rear end, especially with an additional 2' of "lever arm" is not a very good idea.

Now, if you were to stiffen the frame along its entire length, say, by boxing in the frame members, then you might be able to justify what you are planning.

That being said, you will get the argument that the semi-monococque design of the trailer means that the shell is holding up the frame as much as the frame is supporting the shell, and changing that dynamic has its unintended consequences as well. There was at least one thread that I recall participating in, where the thread-starter was experiencing "oil-canning" in his shell as the sun warmed the trailer during the day. The only cause that could be pointed to was the fact that he had rebuilt/beefed up his frame, and now that frame probably doesn't have the give and flex needed to move with the shell as it changes shape due to thermal expansion.

The other argument one might have against extending the frame is that that additional 2' of overhang may make your trailer that much more likely to drag the rear end when entering and leaving you driveway, or any other business that sits higher than the street. I am always suspicious that there isn't an awful lot of actual engineering that went into the design of these trailers, but I would imagine that some thought was put into the basic geometry of the design.

good luck!

[aftermath]

Originally Posted by Belegedhel

...

That being said, you will get the argument that the semi-monococque design of the trailer means that the shell is holding up the frame as much as the frame is supporting the shell, and changing that dynamic has its unintended consequences as well. There was at least one thread that I recall participating in, where the thread-starter was experiencing "oil-canning" in his shell as the sun warmed the trailer during the day. The only cause that could be pointed to was the fact that he had rebuilt/beefed up his frame, and now that frame probably doesn't have the give and flex needed to move with the shell as it changes shape due to thermal expansion. ....

good luck!

I agree with this idea. This is another example of a thread that can go sideways in a hurry. Do people add stuff to the back of their Airstreams? Yes. Do some of them share that they have no problems doing this? Yes, as well. Have some had issues? Yes they have. What you want to do is up to you.



My cousin has an Arctic Fox with a frame you could put a small house on. It is so beefy that I continue to be amazed. As mentioned earlier, these type of trailers start with a huge, strong frame and build the trailer to sit on top of it. Adding something to the back of one of these probably will not hurt the trailer itself but the other issues would remain. The bouncing at the end might damage what you are carrying and could impact the tongue weight. If you do this to an Airstream you can add the possibility of damage to the trailer itself.



Why would you want to do this in the first place? Is it you have run out of places to put your "stuff"? How much stuff do you really need? Threads here talk about not wanting to get an Airstream approved bike rack. Some talk about not wanting a pickup truck to tow and prefer an SUV. Where are you going to put your stuff? And again, how much stuff do you really need?

[joeybravo]

i appreciate your feedback everyone,
i was just wanting to extend the frame via some HSS inbetween the channel frame, adding maybe 1ft -2ft max with roughly 200lbs on the end. bike storage and dive tanks wetsuits, etc.
please see attached.

i will be asking a million questions to this forum over the next few months as i work on my baby.

[joeybravo]

just looking to innovate a bit as we transition to seasonal living.