Building "Adventure Buddy"

[ryanmcrist]

After deciding to downsize from our 24' travel trailer, my wife and I are embarking on building an expedition trailer! The info on this forum has been incredibly helpful. We decided to model it after the Patriot Camper X1, using the Harbor Freight 4x8 trailer ("Super Duty") and leaving it the same bed size.

This is also my first shot at welding, so it should be interesting to see the results. Im a fairly good craftsman with fine woods, so im hoping that some skills transfer over.

Our intention is to build the structure out of 2x2 and 1/2" marine grade ply with epoxy. From there we will have our roof-top tent on a steel support over the main box.

Here are some initial pics!

Looking forward to your input and questions!!

 

[QQQ]

Looks great, are you going to install an off-road suspension and axle?

 

[ryanmcrist]

Yes, I do plan on adding the Timbren suspension. I see a lot of people adding the 3,500lb axle with breaks, but that seems like over kill? Can i get by with adding the 2,000 axle, or are most builds weighing over that amount?

Trying to save some costs where i can!

 

[opp]

Take the time and box the frame maybe one hour .will stop twisting in the frame Timbren suspension a lot of over kill .When you have time go to a3500 axle DO NOT put longer spring on. can mean trouble at higher speeds

 

[old_CWO]

Yes, I do plan on adding the Timbren suspension. I see a lot of people adding the 3,500lb axle with breaks, but that seems like over kill? Can i get by with adding the 2,000 axle, or are most builds weighing over that amount?

Trying to save some costs where i can!

You tend to see a lot of 3.5K axle selection to get the larger spindles and bearings for heavy tire support. It's also the smallest trailer hub size available with the very popular 6 lug bolt pattern that matches Toyota and GM wheels. Additionally, the 3.5K is when you start to more commonly see electric brakes as an option.

Now 3.5K suspension on a trailer that isn't carrying anything close to that is a poor solution. Your trailer will beat up your cargo and pogo around on rough roads. The general idea is to match capacity to load. Timbren does offers axle-less suspension components with large spindles and lighter spring rates to help with that.

I see you are starting with a Harbor Freight trailer chassis. There is a strong cottage industry built around using and modifying these for custom RTT trailers, faux M416s and home built teardrops - do a quick search and you will find a lot of good ideas. Many of them come from a couple of specific gentlemen who are members of this forum as well as others in the Jeep and off road enthusiast hobby. There is also a guy in Oregon with a very nice e-store and web forum. Among many other slick trailer items, he sells a low cost bolt in leaf spring kit that I believe is exactly the right suspension choice for your project. Search it out and you will see what I mean.

The best way to save costs on an adventure trailer project is to keep the weight and tire size minimized as much as possible. As a basic principle, the heavier your trailer and bigger your tires, the more mods and money.

Good Luck!

 

[ottsville]

Take the time and box the frame maybe one hour .will stop twisting in the frame Timbren suspension a lot of over kill .When you have time go to a3500 axle DO NOT put longer spring on. can mean trouble at higher speeds

How does a longer spring translate to potential trouble at higher speeds?

 

[opp]

They flex more and more tork sideways on a short frame.

 

[old_CWO]

They flex more and more tork sideways on a short frame.

Not sure I'm following. Longer springs can be more flexy of course, that's actually why they are often sought after for small off road trailers. I don't understand how that applies more torque sideways on a short frame. I once had a small trailer with long flexy leaf springs and it oscillated or "porpoised" from side to side after a bump - almost like death wobble. Is that what you mean? My issue was easily resolved with shock absorbers and after that it towed like a dream on and off road.

 

[opp]

Yes .With the light frame of HF it will twist at high speed as the spring mounts are at the ends of the frame in high speeds curves. think of taking a piece of thin steel and twisting back forth some thing will give
Oui .Avec le cadre léger de HF, il se tordra à grande vitesse car les supports à ressort se trouvent aux extrémités du cadre dans les courbes à haute vitesse

 

[old_CWO]

Yes .With the light frame of HF it will twist at high speed as the spring mounts are at the ends of the frame in high speeds curves

Okay I get it. You're asserting that longer springs exert more leverage on the frame rails and if/when the springs work opposite each other, it causes frame twisting.

Never observed such phenomenon, but the performance improvement of longer leaf springs on the HF trailers is more than worth the effort to stiffen up the chassis a little bit. The pre-made suspension kit with longer springs sold for HF trailers is mounted to a stout piece of angle steel that strengthens the side rails upon installation. I am sure that's more than enough to prevent any spring oscillation induced frame twisting for these little guys.

HF trailer strength is also tied to the decking like a torsion box. With a rigid deck properly affixed, the chassis becomes significantly more twist resistant. That's why 3/4 plywood or heavy gauge sheet metal flooring is such a good choice. It makes the entire trailer stronger.

 

[rnArmy]

Here's a thread based on building a little adventure type trailer with a Harbor Freight type trailer frame.

https://www.jeepforum.com/forum/f27...ype-trailer-ultimate-build-up-thread-1180456/

Longer springs and shocks made a huge difference (along with the 3500lb axle). The factory slipper springs are way too stiff - they have no flex.

 

[ryanmcrist]

Here's a mid-weekend update for Adventure Buddy!

I chose to stiffen up the tongue and the trailer overall with the addition of a steel bar.

Thanks to Compact Camping Concepts for the tip!



Primed and Painted



Started on the decking with 3/4" plywood. I used the Kreg concealed hinge jig to create the recessed holes to acommodate the exposed bolts on the frame. I'll be coating the bottom of this with Krylon Truck Bed Liner.



Hope I can get further ahead than this by end of next week!

 

[opp]

What was the side on the steel bar.?

 

[ryanmcrist]

What was the side on the steel bar.?

Are you asking what the size was or was there something on the side you were interested in? The steel bar was .25" 2x2. It was a piece of scrap steel that i picked up for $10 at a local steel supply store.

 

[rnArmy]

I believe Compact Camping Concepts also sells a nice bolt-on suspension kit with longer leaf springs. Or they sell the springs separately without the mounting hardware.

Question: What kind of axle came with your "Super Duty" HF trailer frame? Was it a solid round or square tube axle, or some sort of "C" channel axle? A picture would be appreciated.