Teardrops n Tiny Travel Trailers

Thanks for the detail Fred. Yeah, I've been thinking about doing #3 all aluminum, mostly just to learn how . Building these things is addictive.

-Greg

You're welcome, Greg.

Yeah, I've been thinking about doing #3 all aluminum, mostly just to learn how.

Maybe Mike could start a 'Building with Metal' topic. There are a number of members that might contribute their knowledge.

Fred

P.S. This trailer is for sale.

Super build

You make it look so easy. I got this log bookmarked for future ideals.

Thanks Terry. I hope you can make use of some of the ideas in the future.

Speaking of ideas, another friend suggested that I should explain the concepts behind the profile shape. Especially compared to the more traditional 4x8 retro streamlined teardrop shapes.

The cabin is 7' long to reduce weight.

Interior volume: The flat lower front wall & taller flat rear wall increase interior volume & bed length. The interior cabin space, bed length, storage shelving & footwell are quite generous. As is the galley with the work surface tailgate down.

Aerodynamics: The lower front wall really doesn't matter, because that portion of the front is always within the slipstream of the tow car. The only way to improve this would be to round the front corners & blend them in to the curve of roof with compound curves.

As the tow car & trailer move through the air, the trailer strikes the air coming off the top of the tow car. The more rounded the top front, the least the resistance.

The blue line represents the boundary layer of that air. As the roof slopes down at the back, the boundary layer is released creating a vacuum that causes drag & lowered efficiency. By keeping that slope at a shallow angle, the boundary layer doesn't release until the very back.

At that point the flip up at the back strikes the boundary layer & turns it under, helping to break the vacuum & drag, increasing efficiency.

The flip up is my version of the Gurney Wicker. So called because it was developed by American racing driver & Indy car builder, Dan Gurney.

Of course, I have no way of testing my theories other than towing the trailer down the road at high speed (which I have ). However, combined with a suspension matched to the load of the trailer & the large radial tires rated at 1356# & run at 21 psi., the trailer rides smoothly & handles well at speed.

Fred

Thanks for the explanation. I figured you made this one shorter so you have more room for your next
build in your garage.


Hey did I miss it? or did you post the weight of this camper somewhere. ??

You're welcome Terry,

You're right on the amount of space it takes up. There's two in the shop now & room for a third, but I can only use one at a time! So, I'd like to sell one or the other.

Also, size & the fact that so much of the work is done on the bench, makes it convenient for an old man with a worn out back.

Yes & yes. 525#. The specs are in the first post.

Fred

Very, very nice. ...Top notch!

Thank you Sharon,

Compliments from an obviously thoughtful & accomplishing builder are most welcome.

Fred

A good example of what I have been saying for a long time, you are building an aircraft not a tank. What is the final weight?

525 lbs Shadow Catcher.

Fred,

Really clean, professional work.

What are you going to build next?

Did you see my Round Tail trailer on this forum? It was an experiment. It tows like a dream with no loss in fuel efficiency over non-towing behind a pickup with a canopy/camper shell! You're the guy who could improve on it. The tail cone could swing open like a pantry/galley.

My 2 cents.

Best wishes,

Prem

Prem wrote:Fred,

Really clean, professional work.

What are you going to build next?

Did you see my Round Tail trailer on this forum? It was an experiment. It tows like a dream with no loss in fuel efficiency over non-towing behind a pickup with a canopy/camper shell! You're the guy who could improve on it. The tail cone could swing open like a pantry/galley.

My 2 cents.

Best wishes,

Prem

Thankyou Prem,

I am currently building a trailer for forum member, Stacie Tamaki. It is of her own design using my construction methods. Stacie blogs about her trailer here: http://theflirtyguide.blogspot.com/sear ... 0-%20Build

I remember your Roundtail because of the innovation & had saved pictures of it. A stand-up trailer may be in my future also.

Fred

Fred,

NICE shop!

Did you bend that 1" square tube round with a mandrel or by heating it with a torch and working it to shape?

I built two rigs with 1" square tube, but I used exhaust pipe bent on a hydraulic mandrel for the curves. One of them was a 35' bus conversion with a raised roof and one a chassis-mounted jumbo camper on a 1-ton Chevy with dual rear wheels. With a mig welder it went fast. With a band saw instead of the chop saw, it went way quieter.

I'm not kidding about the aerodynamics of that Round Tail trailer. It amazed me that a tall, short standie suffered no loss in MPG over not towing it.

It's as important how the aft airflow gets put back together (laminar) as how it gets parted forward. But since the tow vehicle does almost all of the parting of the air forward, the aft flow is the trailer's responsibility. A stubby airplane wing cross section is ideal for a trailer IF one does a lot of miles. I applied that stubby shape both to the sides and to the top and bottom of the trailer. Were I to do it over, I'd probably put an aluminum belly pan under it like Airstreams have, at least between the wheels from the front to the back.

I'm currently towing the worst of all trailers for airflow: a flat-back cargo trailer. The Air Tabs help a bit. http://www.airtabs.com/main.html and http://www.tnttt.com/gallery/image_page.php?album_id=964&image_id=51602

Prem

Hi! I am new here. Have seen your build and must say I like it alot. It is similar to what I am building, but you have done a professional job for sure...

Prem,

The Northern Lite uses 1" sq. aluminum tube cold formed around a wooden buck as described in a previous post.

Stacies' trailer has 3/4" steel tube formed all in one piece using a torch around jigs on the welding table. I've considered buying square dies for a ring bender. However, butt welding circles together accurately would seem just as tedious as the torch method. I have visions of hydraulic pressured die wheels that would follow around any given shape laid out on the table. Maybe someday.

Fred