The weekender

[Eagle]

Greetings,

Just wondering if there are any new weekender designs or mods and where they are posted.

Not that you have other things to do, Mike.

Eagle

[mikeschn]

Eagle,

You're so funny! But yes, I'll be doing the final plans for the weekender, now that I know what the final arrangement is. They'll end up on the weekender page with all the other stuff.

As for mods, I am currently working on some ribs to turn the back into a 1 piece hatch. I'll be out of town tomorrow, but next week when I get back I'll have some photos for you. I might also frame in the door.

Mike...

[Eagle]

So, have we finished the weekender???

Where is the final plan?

Thanks,

Eagle

[mikeschn]

I didn't have time this weekend to work on it... and when I came home this evening I quickly had to capture an idea... but I'll be getting on it very quickly here...

Are you going to build the 4' version just the way I have it on the webpage? or what modifications are you considering?

Mike...

[Eagle]

Since it will just be me, I imagine I will do the 4' width. I too had a busy weekend (job related).

Not sure if I will go with the weekender or a hybrid of it and one or two others. The hatch is the wall I am running into at this time. I like the "looks" of the weekender hatch, but I think I might do a hatch in the "Road Toad" style (except straight). Depends if I can cram all I want in the galley with the weekender design. Not sure I want to do a curved hatch. Posted some hatch questions, but no replies yet.

Looking for something SIMPLE and hopefully water tight.

Do have time and place to build problems to resolve. Maybe I can get out the graph paper sometime this week and scratch some ideas down. I do not have the time or patience to do a learning curve on a CAD program. Have tried a demo/freebie a time or two. By the time I get something down, I feel I could have "old schooled" it on paper faster and better.

At least I have an a/c unit to build on around.

Eagle

[mikeschn]

I will be finishing the weekender plans, but seeing as how you are already planning on building something different, I'd like to see what you have. Grab a piece of graph paper and sketch it out, and then fax it to me. I'll give you my fax number when you are ready.

The biggest key to keeping the hatch area dry is to overhang the hinge by a little bit. Then almost any seal will keep the water out the sides and bottom.

It's not rocket science. Draw the profile you like best, and then ask if you think it'll work. Chances are, it will!

Mike...

[Eagle]

Looking at the final weekender design, do I have the demensions correct for the eight sides of the profile?

Starting with the 96" floor and going CCW, 18", 22", 28", 51" roof, 46" hatch, 25", and 8.5". Tried to measure off a printout and with an assumed scale, wonder if I got close on the other seven sides.

Any good free CAD's to try and learn on out there?

Thanks,

Eagle

[mikeschn]

Here's a marked print with the final Weekender plans... I've been juggling a lot of balls lately, but I'll get back to this soon.



As for CAD, this one is free for 60 days...
http://www.ironcad.com/product/

Mike...

[Arne]

Has anyone built an angular t/d trailer? I'm asking because my t/d, with rounded front, and width about the same as van, moves around as I go down the highway. I can feel it and see it in the rear view mirror.

I have a 75# tongue weight, which is just about right on target, straight axle, and properly inflated tires.

I can only attribute it to the air spilling off the van hitting the front of the tear and causing some mild buffeting... it is not a major problem, but would think having flat surfaces on the front of the tear would create more, rather than less, buffeting, especially at 65 mph....

[Woody]

My rounded front traditional teardrop buffets alittle in crosswind situations and is felt in the tow vehicle. I had noticed that when the tow vehicle is buffeted it is transfered back to the trailer even more. I think aerodynamics (rounded fronts) are key here, after all an F -16 would fly alot different if you attach a large flat surface perpendicular to the leading edge of the wing.

Woody

[angib]

This may not seem logical, but here goes: rounded-front trailers are significantly LESS stable than square ones.

Square trailers stall in a cross-wind - they're effectively stalled as soon as they move. Stalled bodies do not generate much side thrust (same reason airplanes with stalled wings fall outa the sky).

However a rounded-front (in plan) trailer behaves like an aerofoil and so generates side thrust - this is bad news.

Trailers that are rounded-front (in side view) like teardrops generate lift at the front - perhaps even enough that the hitch load goes to zero - more bad news, as this reduces the sway damping. However this is only likely if the trailer is bigger than the tow vehicle.

What rounded-front trailers are good for is drag reduction. But teardrops don't really count as rounded-front, as the sides are square - only the top is rounded, which is only about 1/3rd of the perimeter.

Andrew

[Laredo]

Are you saying that if a person took the basic weekender dimensions, with a four foot width and the flats on the front, it would create a lot more sway to extend the width 12'' on each side and 'taper' that from the front to the outer edge of the sides? It would look similar to the 'stealth fighter' front end, but instead of slipping thru the air better it would be harder to tow?

[angib]

Laredo,

So much depends on the detail, that it's rash to state that (a) is better or worse than (b), especially when I'm just well read on this subject, not an expert!

There does seem to be a conflict between low-drag designs and low-crosswind-sensitivity designs - they're two different shapes. As I understand it, many modern cars are designed with slightly rounded front corners so that the airflow, from dead ahead, will stay attached as it goes around the corner: but once there is a side wind (ie, the car's speed and the side wind combined make an airflow from, say, 10 degress off centre), the front corners are still sufficiently sharp that the airflow will break away and the car will 'stall', so producing less side thrust.

Please note the overriding principle with teardrops - if the trailer has a smaller cross section than the tow vehicle, then none of this really matters much. It's only when the trailer is significantly bigger than the tow vehicle that it becomes important to consider its shape.

Andrew

[Cary Winch]

Arne,

How much does your teardrop weigh? It would have to be awfully light for a 75lb tongue to work right. Give us some specs, maybe there is a clue here somewhere.

Cary

[Laredo]

Andrew,
thank you.

I have not the gift of CAD and so must clumsily wring from words the image.

If the flat of the front is the 'nose' of the trailer, each side's joint to the nose would be approximately 30 degrees inclined noseward from the side's joint to the outer wall. This would be true in all four of the planes the panels occupy (that is to say, I would equalize this angle on all intersections) if I have this thing configured correctly.

I believe that this would come as close as square joints can to imitating the frontal contour of the tow vehicle -- and since the tow vehicle is a pickup, I cannot be certain of how the frontal edge's aspect ... angle of attack, to borrow yet another aircraft term ... compares with the aspect at the back of the truck.