Not so tiny ultralight trailer build journal?

[Thomcat316]

The "One Big Goal" that can't reasonably be met with a tag trailer is aerodynamic blending from the truck to the trailer. This is a big part of the motivation to build in this style. Yes, I 'm one of those mileage crazies....


I'm going to try to engineer skirted joins from the cab back to the trailer so there's no gap or discontinuity, along with gradual tapers both up/out and down/in/up at the front and rear of the trailer. In addition to this I'll have to figure out just what clearances will be needed for articulation and just how low the trailer floor can reasonably be. I've seen 35' racecar haulers with 7-8" ground clearance, and their drivers tell me it's not too much of a challenge to maneuver, just a matter of not trying the impossible. One feature that will be installed is a long set of 4130 round skid bars to help protect the floor from my own stupidity. I may also bond a sheet of 0.060" aluminum to the underside as road-crap insurance. Another (possibly butt-saving) feature will be the ability to lift the trailer up several inches with its own suspension.

[jstrubberg]

with the design intent of tightly slipstreaming it behind a Dodge Dakota's cab and having a full-size camper that gets 25MPG+ highway

Not to be a noodge, but there isn't a Dakota on the road that will give you that kind of mileage with NOTHING behind it...

My 8 cyl 2nd gen got about 15mpg on average, not towing. Our neighbor ran one of the newer ones with a 6 cylinder for a long time and was pretty proud of getting 18mpg. With a 2wd and a 5 speed, you can probably pull 20-21mpg totally empty and on flat highway.

[Thomcat316]

Point taken! Dakota is like throwing a heavy brick through the air...

The choice was largely driven by the combination of target size, cost and availability - didn't want "full-size", can't afford Tacoma crew cab, can't find S-10 crew cab.

I'm going to use careful design and build (and modification) techniques from the collective mind of the Ecomodder forum, along with swapping in a 3L Mercedes turbodiesel with the stock NV3500 5-speed transmission. So far, in the limited driving I've done with the stock (very badly tuned) V6, I've gotten 22-and-a-little MPG tank-to-tank. This is using a GPS as the odometer, as the tires aren't stock size. The stock Mercedes 300SD gets 26-31 in real life, with a non-locking automatic - if I'm really careful with aerodynamics I think I can make the 25MPG highway; if not, I'll get close. Show me another 28' TT in this consumption class!


The gas S-10 below managed 26.01MPG over 622 miles this past weekend, as loaded...

[OP827]

To have more height and save on weight you could go with a flat platform of just "almost" naked frame vs. standard pickup box in the back. That should give you more space and turning posibilities for the fifth wheel.. Could also get it very close to the cabin to have a better aero shape.

[OP827]

Something like that?

[KCStudly]

Skirt the wheels and run a full belly pan.

[Thomcat316]

OP827 - Yes, something very much like that!


KC - planning on getting all aero, and yes, instead of installing deeeep spoilers and skirts, it's going to be a belly pan and wheel fairings (and spats, and other wizardstuff....)

[conn.rod]

just get one of these


https://www.youtube.com/watch?v=p0NIEblWac4

[mezmo]

These are pretty much an Ultimate TT, maybe the most
advanced in the world - from what I've seen at least - and they
are very pricey, but don't let that stop you from "emulating"
any good design feature they have on your home build. The web
site is good for a trailer envy drool at the least.

Check out the 18ft single axle body design. the front of it is
designed to get down into the cross-sectional area of the tow
vehicle.

http://www.kimberleykaravans.com/

Cheers,
Norm/mezmo

P.S This is a build-friendly forum, so build away...

[OP827]

This is going to be very interesting. Will be watching. Build away!

[Ned B]

Digging through my old posts... Any progress?

[Thomcat316]

Update!! (as requested)

Well, nothing's been built so far - we're still in the "gather the stuff" phase of pre-construction.

"Stuff" so far:
Mercedes diesel donor car for engine and misc parts
Dodge Dakota truck as wished for
Spare transmission to mate to diesel
Large lithium battery pack and associated electronics for solar rig

Other progress:
Many pages of little bloody hardware and systems details decided on and listed
Bunches of fun and odd design details drawn out and ready to go into CAD
Hundreds of links to projects that have successfully done one little bit or the other

We will be taking time off this summer to travel the East Coast with the teardrop - up the Blue Ridge, out to CT by way of Long Island, up to central NH, and back through DC for July 4th. Perhaps this winter we can get the hitch mounted in the truck and get the shell and suspension built. After that, "all" that remains is outfitting....