How do you calculate tongue length?

[nwoods]

I know there must be an ideal parameter for tongue length that factors in tongue weight, wheelbase (CG), turning radius, stability, and misc other factors, but I have no idea how to go about it.

The tongue on my trailer is adjustable. I positioned my adjustable tongue length so the nose box was far enough back to clear my tire carrier on the back of the Jeep when I swing it open to access the rear cargo area. This works, but is it optimal? Surely there must be a more scientific way of figuring out the right length other than the TILR method, right?

 

[ex m38a1er]

Ιt's a compromise between two things.
1st in order your trailer to have the same turning radious as your tow vehicle
the distance from hitch to trailer's wheel hud has to be equal to your wheelbase.
Then you have to calculate your tongue weight(on your travelling mode)
http://www.ehow.com/how_4814480_calculate-trailer-tongue-weight.html
and make sure it does not weight more than 15% of trailer;s total weight...

 

[Titanpat57]

Something also along those lines....

http://www.angib.pwp.blueyonder.co.uk/teardrop/tear84.htm

 

[teotwaki]

subscribing.... :bike_rider:

 

[gabepari]

...1st in order your trailer to have the same turning radious as your tow vehicle
the distance from hitch to trailer's wheel hud has to be equal to your wheelbase.....

There is a little more to it than this. The rear overhang (distance between the rear wheels and the tow ball) of the tow vehicle comes into play as well. A longer overhang helps "initiate" a turn and helps to keep the trailer from tracking to the inside.

If you're handy with CAD or like playing with compasses, try drawing out the different extremes to see how they react.

Gabe

 

[JPNCA]

I just made it so I had enough to jack knife the trailer with out damageing truck or trailer.
Track perfect

 

[nwoods]

I just made it so I had enough to jack knife the trailer with out damageing truck or trailer.
Track perfect

yeap, I do that regularly...as in, every single time I back up! I have had the trailer out on half a dozen trips over the summer, but it is not getting any easier to back up into wherever I need to go. I have found it somewhat easier though, if I let my wife drive and I spot her in. Things don't go nearly so well when she's the one trying to spot for ME

 

[ex m38a1er]

^^^^^^^^^^:smiley_drive::wings::victory:

 

[tclaremont]

Backing a trailer is much easier if you start with your hand at the six o clock position on the steering wheel. When you want the trailer to go left, push your hand to the left. If you want the trailer to go right, you push your hand to the right.

So easy a wife can do it.

 

[JPNCA]

That only works if you can see the trailer:sombrero:

 

[TacoDell]

Backing a trailer is much easier if you start with your hand at the six o clock position on the steering wheel. When you want the trailer to go left, push your hand to the left. If you want the trailer to go right, you push your hand to the right.

So easy a wife can do it.

did you unintentionally state this backasswards ?

It's possible... you might need a wife to help you... LoL

If I'm backing up, starting in a straight line...

if I turn right... the trailer backs left...
if I turn left... the trailer backs right...

It's referred to as counter-steer... and it what initiates the direction that the towed unit will lead.

Once the trailer is backing in the direction you'd like...
then the counter steer would stop and normal steering would follow... so as to re-align the tow rig to the trailer and continue backing.

I will agree on the 6 O'clock hand positioning tho'

 

[fingas]

did you unintentionally state this backasswards ?

It's possible... you might need a wife to help you... LoL

If I'm backing up, starting in a straight line...

if I turn right... the trailer backs left...
if I turn left... the trailer backs right...

It's referred to as counter-steer... and it what initiates the direction that the towed unit will lead.

Once the trailer is backing in the direction you'd like...
then the counter steer would stop and normal steering would follow... so as to re-align the tow rig to the trailer and continue backing.

I will agree on the 6 O'clock hand positioning tho'

I think he was referring to the direction of movement of the hand. When you have your hand on the wheel at 12 o'clock and move your hand to your left it will turn the wheels opposite of the direction than if your hand was at the 6 o'clock and you moved your hand in the same direction. IOW with your hand at 12 if you move it left your wheel turns counter clockwise, with your hand at 6 if you move it to your left the wheel turns clockwise.

 

[Toolman]

I have been driving / pulling trailers for over 25 years now.. I learned from my Dad when I was 14 helping him launch the boat down the ramp, with many other boats and rigs pulling in and out. It was easier for me to drive the Van, and trailer than the boat.

My tips
1. go slow, and always check your mirrors
2. when starting out (novice) use the 6 o'clock method, it works
3. the longer the trailer the easier it is to reverse
4. practice in an empty parking lot to get the hang of it
5. you can always pull forward if it gets out of whack
6. watch the front end of your vehicle to make sure you're not running into anything.... my neighbor was backing his boat into his drive way and took out the side of his house and front fender,blinker, and bumper of his truck... oops

when you get good you can parallel park your rig

 

[TacoDell]

I think he was referring to the direction of movement of the hand. When you have your hand on the wheel at 12 o'clock and move your hand to your left it will turn the wheels opposite of the direction than if your hand was at the 6 o'clock and you moved your hand in the same direction. IOW with your hand at 12 if you move it left your wheel turns counter clockwise, with your hand at 6 if you move it to your left the wheel turns clockwise.

Yeah... now it makes sense... guess I had a brain fart... my bad.

 

[Errant]

That only works if you can see the trailer:sombrero:

x2! I can't see my M100 behind the Disco, which makes it difficult. This weekend we packed differently for the way home, and stacked some light stuff higher to be seen from the mirror. It made it lots easier, but I still need more practice