In Cab Operated Electric Telescoping Trailer Tongue
 

My design to draw a trailer up for highway aerodynamics, and extend it back for tight turns around town. All done without having to leave the car.
https://www.youtube.com/watch?v=UyYONaqJ8zU

After I designed this, I found the heavy duty, probably hydraulically operated, version on You Tube. Their version uses lock pins. My version counts on the gearmotor to prevent creep back. I will have a red light in the car to tell me that the trailer is pulled up tight, and if it creeps back, the light will go off, and I will push the "Draw Up" button. But I think the gear reduction in the gearmotor will be hard to run backwards through the all thread.
Here is the commercial version:
https://www.youtube.com/watch?v=KY0ugxC8RPo

I'm bothered by the way the inner or outer surface of each square tube is a bearing surface. Teflon buttons or something?

Why couldn't you have the motor at the hitch end? Could you get the gear drive inside the 3 1/2" pipe? Cut out two sides of the pipe and box the opening?

Good suggestion. I'd have to use the .188 wall 3 1/2 inch tube in place of the .250 wall to make room for the buttons. Hope the mild steel won't bend.

Just seemed more sturdy to keep the front tube intact, and go into the non-load bearing end of the rear tube. I may overhang the carrier a bit, and protect the motor from rain.The Teflon idea is good, though. Will let me use lighter tubing.

I AM a bit concerned about the shortened wheel base in Highway Mode. I've heard that shorter trailers are more skittish.

I was taught that it's the ratio between the TV axle/hitch and hitch/trailer axle. Moving the hitch closer to the tow vehicle axle is [proportionally] equivalent to lengthening the tongue.

slowmover can tell you about a swinging hitch that does something similar. I don't recall the brand name or how it locks (or not).

How can I find his posts?

A Jim Hensley patented hitch locks & unlocks. 120# without vehicle hitch receiver.

PULL RITE used to make a swinging constant-distance hitch. But it weighed over 400#.

I’ve my doubts this’d work well (ROI), but pulling the trailer innclosexwouldnt otherwise concern me.

Moving the trailer axle rearward on trailer frame is an old method for better stability. But can trailer design handle it? It increases forces at other end (strain).

My design keeps the load centered over the axle, moving the load and axle as one unit. Only thing I see is that the horizontal center of gravity moves forward slower than the load and axle as the trailer is drawn up to the tow vehicle. Would need to locate the axle so that at full forward, there is still 200 lbs on the ball, but as the trailer tongue extends, that ball weight would increase.
(Have I got this backwards?)

Problems in Towing come with maintaining straight-line stability. Overly forward COG contributes.

Too Fast for Conditions can happen in seconds.

I’m not qualified to say whether or not your idea will work. But I’m not comfortable when I’m passed on the road by someone with an overloaded hitch rack. When that rear axle loses traction, it’s all over. Uncontrollable.

But a trailer spreads that load. Until it’s out of alignment. The shorter that distance from axles the better, to some degree. Just remember that trailers do not lend stability.

As before I don’t quite think the time & effort will pay. A trailer? Great.

Changing combined vehicle dynamics? Maybe not great.

Low MPG a regular RV owner complaint. If a telescoping trailer tongue on a HI-LO could have worked, I think we’d have seen it.

A perfect storm is where all the bad pieces come together at once. On the highway, that’s life-changing. Literally no time for correction or stopping.

FE is about good predictable performance. A high, a low, and a money-in-the-bank accurate number for planning highway trips.

My pickup can do 24-mpg without end (exceptions to mountainous or non-Interstate). Safe to budget number. But there’s less friction my running 62-mph than 58-mph. An easier day on the road.

Easier = higher level of attention & awareness as the day goes on.

A trip plan is what covers the transitions. The margins. How to preserve 10ths.

As to the trailer: I’d MUCH rather have the trailer than an overloaded tow vehicle. Easier on the vehicle & driver. But trailers too small for brakes present problems of their own. As do single versus tandem axle (tridem is awesome).

Best brakes on a trailer (mine is 35’) means a shorter stopping distance than the tow vehicle solo. The trailer brakes LEAD the tow vehicle in time & application force. Brake control is also what stops trailer snaking (oscillation; sway).

The aero can be addressed. A telescoping tongue would not be my approach past storage.

.

Thank you.Guess I'll concentrate on forward panels, perhaps receiver or ball mount mounted. I appreciate your knowledge.

Log trucks, for example.

You can get closer coupling with a single wheel trailer. I invoke the name BamZipPow.

http://i.imgur.com/lPaURnC.jpg
https://ecomodder.com/forum/showthre...ows-31144.html

I have built trailers and I wouldn't attempt it.
My 4x8 trailer pulled by my leaf reduces it's range by maybe 20%.
That thing is so small it's going to barely do anything to the mileage.
You have a prius so you don't even have to worry about running out of battery.

Ideally the distance from your hitch to your axle would be about the length of that cargo capsule, then about 2/3 of the capsule would be in front of the axle.
You need stability. That does not look like a stable design at all.

Slowmover has talked me out of it

Yes, complete coupling, but would require a swivel setup to allow the rear of the trailer to swing out on turns. Not sure I want to try that, or the oscillating rear wheel that might result. Probably just build a triangular gap filler.

Those dimensions pretty much match with the original trailer design. 2/3 forward? I thought the specs were (at least 200 lbs on the coupler.) Thanks for your help. Guess I don't need to re-invent the wheel.

I really REALLY like Knox & Aerostealth on trailers behind buses, so to speak.

I’m in favor of trailers, in general.

I’ve loved BZPs work since he got started.

It’s the only way to RV camp, IMO (a lifetime of experience)

But it has to give more than take.

This is where the good threads start. Have you taken a look at Dark Aero?

Do you have any use besides the aerodynamics? If not a collapsible boat tail is called for. This was modeled for a VW Type II, but something similar could be adapted.

https://ecomodder.com/forum/member-f...pe-ii-boat.jpg

Fiberglass rods and rip-stop nylon. Follow Mair instead of Hucho. The rigid floor could have a skateboard wheel that flies above the ground. Like Dark Aero without the weight and oscillating tail wheel.

https://ecomodder.com/forum/member-f...d-image-1.jpeg

You guys have helped me a lot. I've abandoned the telescoping tongue, and will now modify the main body of the Harbor Freight trailer to better fit the X-Cargo 20 Cu. Ft. carrier, I will splice in a couple of 24 inch pieces of angle iron to add 19 inches to the main frame. Relocating the axle to possibly gain a longer WB for stability.I will possibly use some gap filling sliders ahead of the carrier to smooth the airflow. The first picture is the stock frame illustrating the hangover that I dislike, and the second picture is the frame stretched 19 inches.

So there will be an electric screw jack at 'A'?

How many inches wide is the carrier?

I think that's a great idea.

For rebuild version 1 of my 4x8 trailer I had the wheels pretty far back. Nearly 6 feet back on an 8 foot trailer deck. It rode great. The idea was I would tow it with my suburban so if there was 500 lb of tongue weight, no problem. Just load it fast and slopy, no problem.
Then for version 2, it was being mostly car towed so I put the axle between 1/2 and 2/3 the way under the length of the deck to better control tongue weight. Now if I don't load it correctly I get trailer sway really bad.

With that setup I would be surprised if you saw a 10% fuel economy hit.

No, I meant that if I move the tongue further back, "A" would go with it. The tongue bolts into that crossbar, and I want to keep it so.
The carrier is 36 inches wide and 67 inches long.

36x67" on a 40" frame. The square frame under the rounded carrier is suboptimal. The carrier is probably thermoplastic and can't be widened. While you're lengthening the deck you could narrow it to 32".

Else just put a skirt on it.

Yes, well I plan to lngthen the box frame by 19" and put 3/4" plywood under the carrier.

I'm sure you meant "36". I have thought of using the extra plywood to build a lead up ramp to the fenders, and possibly a side skirt on hinges so I can change the tires. Not sure if the side skirt's extra weight is worth it.

What's the inside dimension of the floor in the carrier?

Unless you have the Harbor Freight trailer already I'd look for a T-frame

https://www.tyronesnelltrailers.co.u...frame3-500.jpg
https://www.tyronesnelltrailers.co.u...road-trailers/

The overhanging HF trailer would be what I believe they call, in the UK, a 'dogs breakfast'.

Check out this:

https://ecomodder.com/forum/member-f...untitled-4.jpg

There's not much difference from 0.558 to 0.611. If it's smaller than the tow vehicle, it might offer something for some part of the wake to reattach to.

It's lower than the tow vehicle, and I plan some gap filler

It's lowr than the tow vehicle, The Harbor Freight frame will be stretched 19 ", and I plan some gap filler

I spent too much time trying to find one of Bucky's more obscure inventions, the Mechanical Wing. I eventually found it's name in a book so this turned up:

http://3.bp.blogspot.com/-aYf43U1X5_...nical-wind.jpg
http://3.bp.blogspot.com/-aYf43U1X5_...nical-wind.jpg

Note the 2nd hitch to locate the deployable box. But I did find this.

https://ecomodder.com/forum/member-f...8372-blue2.jpg

Yep!

Paint & matching wheels (alum covers) is an excellent idea. That’ll get you the thumbs up. Admiration.

https://ecomodder.com/forum/member-f...llmystery1.jpg

Pontoon fenders.

I was thinking of painting the lid to match the car, but the trailer has 12" wheels, and my Prius has 15'ers

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NEW, SAFER IDEA FOR VARIABLE LENGTH BALL MOUNT.

When you're backing a trailer the length ratio of tow vehicle rear axle/trailer axle affects control-ability. This goes the wrong way for that.

I know it sounds shortsighted, but I plan to park in a way that I don't have to back. I really like my earlier idea, the one someone didn't like because they thought a load bearing tube shouldn't be sliding in and out of another tube. That one would keep the coupler and ball in the same location and shorten or lengthen the tongue for aerodynamics or maneuverability.

I have a failed VW Type III jack. Unlike the Beetle jack it uses a worm gear and under load the worm came adrift at one end. My camera has failed or I'd take a picture.

Your current [previous] design is possibly the best so far.

Well, my "NEW SAFER IDEA" has the problem of moving the ball back, and amplifying any up/down left/right movement of the car, Though this would be in town, extended, at lower speeds. My older, telescoping tubes under the trailer keeps the ball in the same place, near the bumper, but by drawing the tongue under the trailer on "suck up" moves the C/L of the trailer back, lightening the weight on the ball. They both change the weight felt on the receiver, but the "NEW SAFER" design adds unwanted sensitivity when extended.

Maybe I need a bit of both.

I guess you'll find out when you try.