Advice on tear-down/rebuild?

[SettingOutSoon]

I want a 5th Wheel/TH about 38' long, and I'm debating whether to build from scratch (on a drop deck trailer) or buy a cheap, used 5th Wheel/TH and tear it down to the "foundation" and rebuild. (I've given up the idea of moving prefab walls, and I want a structure that will support a rooftop deck.) Any advice?

What chassis would you recommend? Three axles much better than two? Newer Thor or Forest River better than older Nu Wa, Newmar or Travel Supreme? What should I be most focused on?

[SettingOutSoon]

That is a great thread, I wasn't watching the truck camper forum either. Will look into structural engineers, thanks.

[BoonHauler]

Hey, I was just over at the TC sub-froum and read through a thread over there that you should as well. A lot of the same issues are being discussed that you could modify/tweek to suit your build, here's the link...

Our custom true flatbed truck camper build thread

[BoonHauler]

SettingOutSoon wrote:
I was hoping I could place them below the floor almost anywhere and run lines. No?

I know a structural engineer I hired once when renovating a quadraplex. (I thought the guy was going to make me pour enough concrete to build the Hoover dam.) Do you think the average structural engineer would be adequate for this, or is it a specialty?

As for your plumbing you should do a preliminary (plumbing) floor plan and an elevation drawing. These two drawings will give you an idea of where and where not to install plumbing lines. Of course the supply lines (H&C water) are the easy ones as they do not require grading (sloping), It's the drain lines you'll need to get worked out right away.

I myself did a 3" scale drwg to get my plumbing worked out and even after all that work I still changed a few things once I got around to the actual fabrication itself.

As for a structural engineer, all of them are farmilar with ground acceleration (earthquakes) but most if not any are farmilar with dynamic acceleration associated with moving travel trailers, this is where you will need to find a very creative one and one I was unable too find.

Being that I come out of the trades myself and have had a lot of exposure to structural engineering I was able to do that task for my project. The only downside to that has been a little overbuilding on my part and that's why I mentioned that next time around I'd lighten some of the framing members.

As you're well aware of engineers tend to work with 100% safety factors at a minimun, if not more.

[SettingOutSoon]

Thanks Boonhauler. The design is intended to be 5th Wheel (front room is raised), but the outside looks like a box due to the basic floorplan software I was using. I am aware that the tongue weight should be a certain percentage and the weight needs to be distributed properly, but I haven't gotten as far as estimating and adjusting for that yet. This might explain why I find no floorplans similar to what I want 🙂 As for the plumbing, I haven't learned yet what my options are as far as placement, distance from fixtures, etc. I was hoping I could place them below the floor almost anywhere and run lines. No?

I know a structural engineer I hired once when renovating a quadraplex. (I thought the guy was going to make me pour enough concrete to build the Hoover dam.) Do you think the average structural engineer would be adequate for this, or is it a specialty?

[BoonHauler]

SettingOutSoon wrote:
I had not read that thread, but thanks. My brother, a Hollywood construction coordinator, is the only person I know who might be able to accomplish what you've done, but it's way beyond my means to even contract out. I'm looking forward to seeing photos of your first expedition.

I will look into the Desert Fox (clarification: Northwood Mfg 5th Wheels). You considered it because of the quality of the trailer? Or was it more about the clearance? Any other thoughts on what platform a jackleg rehabber might start with?

The Desert Fox trailers were somewhat setup for boondocking. They had larger tank capacities and more insulation than most standard TH's. Again, I decided against this approach as it did not meet the standards I was looking for as I would of had to rework the frame (chasis) itself and this was probably the biggest reason for going ground up. Why not just start from scratch and do it right rather than swiss cheesing a frame.

I didn't like the idea of wood framing as well.

[BoonHauler]

SettingOutSoon wrote:
By the way, this is what I have in mind. I agree with your comments in the above-referenced thread: no slide outs for me:

http://www.pinterest.com/pin/420734790160283716/

http://www.pinterest.com/pin/420734790160283840/

http://www.pinterest.com/pin/420734790160283704/

http://www.pinterest.com/pin/420734790160283939/

Your toilet and shower location is right over top of where the axles would most likely be so that would interfere with the holding tanks. Looks like you would need to have a gray water tank under the kitchen area was well.

You'll need shearwalls perpendicular to the long axis of the trailer to cancel the rotational loading from the dynamic forces associated with acceleration & deceleration in the structure. The wall behind the shower and the wall seperating the kitchen / living areas would both need to be strengthened as well as the front and rear walls. Remember, shearwalls do not like to have big holes cut in them.

You'll need a strong frame to cancel the bending moment in the long axis or your sliding patio doors could pop right out of the frame.

Do you have access to a structual engineer? If so you may want to run this preliminary design by them, they should understand what I'm talking about.

Where were you thinking of putting the potable water tank/s?

This design looks like it would be a bumper pull, is that what you're after? Your design appears to be tonque heavy. You need to be concerned about having the axles too far forward as that will make vary unstable towing characteristics.

[SettingOutSoon]

By the way, this is what I have in mind. I agree with your comments in the above-referenced thread: no slide outs for me:

http://www.pinterest.com/pin/420734790160283716/

http://www.pinterest.com/pin/420734790160283840/

http://www.pinterest.com/pin/420734790160283704/

http://www.pinterest.com/pin/420734790160283939/

[SettingOutSoon]

I had not read that thread, but thanks. My brother, a Hollywood construction coordinator, is the only person I know who might be able to accomplish what you've done, but it's way beyond my means to even contract out. I'm looking forward to seeing photos of your first expedition.

I will look into the Desert Fox (clarification: Northwood Mfg 5th Wheels). You considered it because of the quality of the trailer? Or was it more about the clearance? Any other thoughts on what platform a jackleg rehabber might start with?

[BoonHauler]

SettingOutSoon wrote:

John&Joey wrote:
The one's I've seen almost always started out with some form of a cargo trailer, and went from there.

I've been thinking about that. BoonHauler, what do you think of a cargo trailer as a platform?

No quite sure what you mean by a 'cargo trailer'?... could you be a little more specific?

Race trailers or car carriers have to low of a roof and for the most part are not 'walk on' roofs. The other problem I have with this type trailer is the low ground clearance.

I was originally thinking a Desert Fox trailer would be a good candidate for a teardown/rebuild but the more I thought about the work envolved the more I kept leaning towards a ground up build as I eventually decided to do.

Again, my requirement was a full on boondocker setup for unimproved roads and fulltime living.

FYI, my trailer is 36' 2", 14 foot garage with a 22 foot living quarter.

You really need to define what exactly you want the trailer for and build for that requirement.

I spent nine months doing research, engineering, and model building before I ordered one piece of steel.

Did you get a chance to read through this Thread of mine?

[SettingOutSoon]

John&Joey wrote:
The one's I've seen almost always started out with some form of a cargo trailer, and went from there.

I've been thinking about that. BoonHauler, what do you think of a cargo trailer as a platform?

[John_Joey]

Thanks for posting back, that all makes sense to me.

Most don't do what you're asking for, but I do see them. The owner/creators seem pretty happy with the results after it's all done. The one's I've seen almost always started out with some form of a cargo trailer, and went from there.

Good luck on your project.

[SettingOutSoon]

QUOTE: "I personally would stay away from SIP's for the construction of a TH or any other TT for that matter because of the dynamic forces that trailers generate by being towed (wind loading, weight shifting, braking, etc). To me you'd constantly be chasing leaks (water and air) and all the other problems that trailers incure due to all the bending and twisting they encounter. In engineering terms it's called 'rotation'."
---------

I don't have the expertise to exactly pinpoint why this sounds right, but it does. Maybe it's just the idea of dragging ANY cracker box house down the highway at 70 MPH and then down dirt roads for very long!

My problem is that I can get a wood-framed or SIP panel house build pretty cheaply, and even if my guys have a steep learning curve attaching it to the frame and doing RV plumbing, it's doable. To do what you did--with steel fabrication, etc.--I think I'd have to get a factory to do it for me, at great cost.

Any idea how I could find out which older model 5th Wheels and THs *were* framed strongly? Are there some out there where we could gut and reconfigure?

[SettingOutSoon]

John&Joey wrote:
Do you mind me asking what your ultimate goal is? Is it to save money, or to get a unique rig to fit a specific event. Just wondering.

Don't mind at all, maybe you have some good advice. My last child goes to college this year. I'm selling the big house (I'm single and 52), and want to (a) live mortgage-free and (b) enjoy life from my rooftop deck, moving my home/office between the mountains (grandkids), Washington DC (work) and the beach. That's my idea of a good life for an old guy who doesn't have to live just for his kids anymore. Not really planning to hit the highways and see the USA anytime soon.

There are two reasons I want to build. First, I've looked at hundreds of RVs, and I just can't see a way to adapt them to what I want. If I could afford a class A toy hauler and pull a Smart Car into the garage, I might. Otherwise, I need a towable that is strong enough for a rooftop deck. I'd also like to open up the back (TH ramp) or the side (fold down patio), so that I don't feel cooped up. I could buy a cheap toy hauler and renovate it to my needs, but they're built so flimsy! What is there to work with??

Second... If I could build anything, I'd love to put a more or less conventionally built modular unit on a trailer, that I could *dock* on my land as part of my permanent homestead. That's looking more and more like a luxury I can't afford right now, but if you're interested in what a Texas architect built like that, here's a very cool example:



Source: http://andrewhinman.com/images/portfolio/02-locomotive/5.jpg

[John_Joey]

Do you mind me asking what your ultimate goal is? Is it to save money, or to get a unique rig to fit a specific event. Just wondering.