Andersen Weight Distributing Hitches - Page 4 - Fiberglass RV


Reply
 
Thread Tools Search this Thread Display Modes
 
Old 07-27-2013, 09:37 PM   #43
Senior Member
 
Byron Kinnaman's Avatar
 
Name: Byron
Trailer: 2006 Scamp 13' towed with a 2005 Dodge Dakota 4.7l Magnum W/full tow package (over kill)
Oregon
Posts: 6,306
Registry
Quote:
Originally Posted by rabbit View Post
I ain't no train driver but I find it pretty simple to visualize a vertical and a horizontal plane and forces acting primarily, substantially, mostly, totally in one or the other. I sense the argument with reference to the action of the Anderson tending to the horizontal and an adverb to be established.

jack

I've been trying to understand how the forces in vertical plane work for that WHD? hitch. As I see it the the restriction of the vertical movement would be caused by the friction between the ball and the coupler clamp. The tighter the chains are the more friction between the ball and coupler clamp. (the clamp is my word for lack of a better word, it's the part of the coupler that tightens down against the ball when you latch the coupler).

Also the tighter the chains the more presser applied to the ball tapered pin and friction sleeve. The pressure would increase at the bottom and top in opposite directions the tighter the chains. The chains pulling back and coupler pushing forward.

Anybody else have a better explanation?
__________________

__________________
Byron & Anne enjoying the everyday Saturday thing.
Byron Kinnaman is offline   Reply With Quote
Old 07-27-2013, 09:41 PM   #44
Moderator
 
Jim Bennett's Avatar
 
Name: Jim
Trailer: 2017 Escape 5.0 TA
Alberta
Posts: 4,722
Registry
Quote:
Originally Posted by Byron Kinnaman View Post

Anybody else have a better explanation?
Did you not see my explanation to Jack? I thought the Hitch on the backside 'splained it all.
__________________

__________________
2017 Escape 5.0 TA (January 26)
2015 Ford F150 Lariat 3.5L EcoBoost
2009 Escape 19 (previous)
“Most folks are about as happy as they make up their minds to be.” — Abraham Lincoln
Jim Bennett is offline   Reply With Quote
Old 07-27-2013, 09:57 PM   #45
Senior Member
 
Byron Kinnaman's Avatar
 
Name: Byron
Trailer: 2006 Scamp 13' towed with a 2005 Dodge Dakota 4.7l Magnum W/full tow package (over kill)
Oregon
Posts: 6,306
Registry
Quote:
Originally Posted by Jim Bennett View Post
Did you not see my explanation to Jack? I thought the Hitch on the backside 'splained it all.
I think you need to look at where the forces are and the direction. As I see it as the chains are tightened the bottom of the ball (under the hitch, attached to plate) is pulled back forcing the coupler to apply forward force the to ball. You would have equal forces pushing on the top of the ball and pulling on the bottom of the ball. All the forces would be contained between the tongue, the coupler and ball. I don't see anyway those forces can be transferred to any other part of the tow vehicle. The only left is friction.

I'm surprised you don't understand vertical and horizontal planes. I'll explain. Side motion of the trailer around the ball would be on the horizontal plane. Up and down motion of trailer around the ball would be on the vertical plane.
__________________
Byron & Anne enjoying the everyday Saturday thing.
Byron Kinnaman is offline   Reply With Quote
Old 07-27-2013, 10:26 PM   #46
Senior Member
 
Byron Kinnaman's Avatar
 
Name: Byron
Trailer: 2006 Scamp 13' towed with a 2005 Dodge Dakota 4.7l Magnum W/full tow package (over kill)
Oregon
Posts: 6,306
Registry
I see one other possibility. With enough tension on the chains the friction between links might be able to provide some of the same characteristics as torsion bar. That's a bit of a reach.
__________________
Byron & Anne enjoying the everyday Saturday thing.
Byron Kinnaman is offline   Reply With Quote
Old 07-27-2013, 11:03 PM   #47
Junior Member
 
Name: David
Trailer: Looking
Texas
Posts: 11
I'm not sure why everyone is so worried about what force is applied to the ball and hitch on the rv... the weight is already there when you hook up the trailer, grease the hitch on the rv and move on. It's a round ball going into a round coupler... and I can't recall hearing from anyone they had to replace their hitch or coupler because it wore out. But then most people I know actually perform maintenance on their vehicles... let's see, grease the coupler and lube the release...

18 wheelers drive down the road putting a whole lot more weight on the hitch setup (granted it's a 5th wheel) and the only thing protecting those two surfaces is grease... and I dare so the vast majority of them drive a whole lot further than you in a years time. The whole time I drove truck, I only got the 5th wheel greased at regular oil changes, 15k miles +/-. Never having replaced a 5th wheel plate because it wore out.

WDH takes the trailer and spans the load more evenly from front to back so you don't have a "heavy" spot at the hitch point. That causes the front wheels of the tow vehicle to become less in contact with the road... creating a dangerous driving condition. Wait until winter, go find an icy road, hook up a heavy trailer and go for a ride... you'll figure it out in a very short time. A WDH is just meant to put the front tires back on the ground.

And the old dated system does it very well. Simple, uncomplicated and very rarely "breaks".

And a WDH really isn't meant to correct sway, like when you get passed by a big rig... don't start confusing the two. Sway control may or may not be a by-product of a WDH, but it's not it's purpose.

You can buy a WDH, a WDH with sway control (common name is 4point hitch) or add sway control to your setup. But you aren't buying a WDH that corrects for sway. The friction WDH provide sway control, but it does so by not providing as much weight distribution... tighten those bar up too much, and you won't be able to corner.

The anderson you guys are talking does the same thing... only the turning will never be an issue. But you also loose some of the weight distribution.

In this instance you are not going to be able to get your cake and eat it to.

I suspect the anderson is a very good choice for the trailers such as the Scamp, Casita and so on because of their overall weight, I can't see it being a good choice for trailers with some approaching a 1000# + tounge weights.

Neither of my HiLo's sway when towing. I don't have any sway control on either. The reason? They are only about 6' high when being towed, so the lateral wind forces have a lot less to work with.

Don't over think this too much... next thing you know, you'll be ordering a $3,000 Hensley for your 13' Scamp.
__________________
David78073 is offline   Reply With Quote
Old 07-28-2013, 12:21 AM   #48
Senior Member
 
Jared J's Avatar
 
Name: Jared
Trailer: 1984 19' scamp
Kansas
Posts: 1,610
It makes perfect sense to me, how it works. I completely disagree with how it works with the coupler, though. IMHO, it would be a requirement to run a bullydog coupler with that setup.
__________________
Jared J is offline   Reply With Quote
Old 07-28-2013, 12:23 AM   #49
Junior Member
 
Name: David
Trailer: Looking
Texas
Posts: 11
Quote:
Originally Posted by Jared J View Post
It makes perfect sense to me, how it works. I completely disagree with how it works with the coupler, though. IMHO, it would be a requirement to run a bullydog coupler with that setup.
Why is that?
__________________
David78073 is offline   Reply With Quote
Old 07-28-2013, 12:29 AM   #50
Senior Member
 
Jared J's Avatar
 
Name: Jared
Trailer: 1984 19' scamp
Kansas
Posts: 1,610
Quote:
Originally Posted by David78073 View Post
I'm not sure why everyone is so worried about what force is applied to the ball and hitch on the rv... the weight is already there when you hook up the trailer, grease the hitch on the rv and move on. It's a round ball going into a round coupler... and I can't recall hearing from anyone they had to replace their hitch or coupler because it wore out. But then most people I know actually perform maintenance on their vehicles... let's see, grease the coupler and lube the release...
Grease has nothing to do with it. That little latch behind the ball on most couplers was never meant to take that kind of force. Under the right (wrong) conditions, you're putting the trailer weight and a large part if the vehicle weight on that little latch with the Andersen setup.

A fifth wheel has nothing to do with this discussion. The jaws on my fifth wheel have 1-1/8" thick hardened steel to wrap around the 2" kingpin on my scamp. That doesn't come close to the little 1/8 or 3/16" steel latch behind the ball on most couplers.

Oh, and I've replaced several couplers because they were so thin, they were starting to bulge on top. To be fair, I would be amazed if it got that way behind most of these light campers.
__________________
Jared J is offline   Reply With Quote
Old 07-28-2013, 12:31 AM   #51
Senior Member
 
Jared J's Avatar
 
Name: Jared
Trailer: 1984 19' scamp
Kansas
Posts: 1,610
Quote:
Originally Posted by David78073 View Post

Why is that?
Because it is using the coupler latch to hold up the trailer and vehicle under some circumstances. That was never designed to take that force.
__________________
Jared J is offline   Reply With Quote
Old 07-28-2013, 07:54 AM   #52
Moderator
 
Jim Bennett's Avatar
 
Name: Jim
Trailer: 2017 Escape 5.0 TA
Alberta
Posts: 4,722
Registry
Quote:
Originally Posted by Byron Kinnaman View Post
I think you need to look at where the forces are and the direction. As I see it as the chains are tightened the bottom of the ball (under the hitch, attached to plate) is pulled back forcing the coupler to apply forward force the to ball. You would have equal forces pushing on the top of the ball and pulling on the bottom of the ball. All the forces would be contained between the tongue, the coupler and ball. I don't see anyway those forces can be transferred to any other part of the tow vehicle. The only left is friction.
This tension in the bottom, combined with the compression in the top make for one heck of a torque on the ball hitch, twisting it forward, and because it is affixed solidly to the tow vehicle, the this torque forces the front of the tow vehicle down.

See my explanation to Jack with imagining this setup hooked to your backside. If your reckoning was true, you would not fall forward.
Quote:
I'm surprised you don't understand vertical and horizontal planes. I'll explain. Side motion of the trailer around the ball would be on the horizontal plane. Up and down motion of trailer around the ball would be on the vertical plane.
My education money was fairly well spent, I did learn how to discern between horizontal and vertical. I just don't see what horizontal movement has to do with weight distribution. Potential for sway, yes.
Quote:
Originally Posted by Jared J View Post
It makes perfect sense to me, how it works. I completely disagree with how it works with the coupler, though. IMHO, it would be a requirement to run a bullydog coupler with that setup.
Quote:
Originally Posted by Jared J View Post
Because it is using the coupler latch to hold up the trailer and vehicle under some circumstances. That was never designed to take that force.
I have wondered along the same lines, as there is a fair bit of pressure on the hitch retaining system of any type of hitch. and no doubt the bullydog hitch would suit better. However, I have not had any issues, and have not heard of any either.
__________________
2017 Escape 5.0 TA (January 26)
2015 Ford F150 Lariat 3.5L EcoBoost
2009 Escape 19 (previous)
“Most folks are about as happy as they make up their minds to be.” — Abraham Lincoln
Jim Bennett is offline   Reply With Quote
Old 07-28-2013, 08:40 AM   #53
Senior Member
 
rabbit's Avatar
 
Name: Jack
Trailer: '98 BURRO 17WB
Delaware
Posts: 2,548
It may be that the chain produces a force tending to pull the shank of the hitch head CCW toward the ground, and tending to produce a semi-rigid arch in the tongue/tv connection which can be read as weight added to or removed from the several axles My SWAG is that the force produced, given the vector along which it's produced, is inferior to the levering force applied by a spring arm. This is only a hunch, fellers. I don't have a sheepskin to hang it on.

I notice that the AS boys are complaining that the anchor yokes for the chain are easily displaced from their initial position on tongue members. Whatever force is available is negated by that glitch. I would like to see the before and after numbers on wheel well hgt. in Byron's table. A link would presumably provide a legible version the interpretation of which would be more than wishful thinking.

jack
__________________
rabbit is offline   Reply With Quote
Old 07-28-2013, 08:50 AM   #54
Senior Member
 
cpaharley2008's Avatar
 
Name: jim
Trailer: 2016 2ndGen Escape19 Prairie Schooner pulled by 2014 Dodge Ram Hemi Sport
Pennsylvania
Posts: 6,398
Registry
Jack,
You are on the right track. Like it was stated earlier, it is perfect for t/w less than 500#, more than that and it's efficiency drops, as noted on the AS forums which all have heavy tw. The ability to grasp the frame is via bolt and a set screw, both of which will move if too much force is applied. The Lance 1575 which was used in the table has a very light t/w and I was surprised someone used a w/d hitch as the lightweight frames on the Lance is made by (Norco I think) were riveted and they did not recommend using a w/d setup.
__________________
Jim
Never in doubt, often wrong
cpaharley2008 is offline   Reply With Quote
Old 07-28-2013, 10:05 AM   #55
Senior Member
 
Byron Kinnaman's Avatar
 
Name: Byron
Trailer: 2006 Scamp 13' towed with a 2005 Dodge Dakota 4.7l Magnum W/full tow package (over kill)
Oregon
Posts: 6,306
Registry
Quote:
Originally Posted by Jim Bennett View Post
This tension in the bottom, combined with the compression in the top make for one heck of a torque on the ball hitch, twisting it forward, and because it is affixed solidly to the tow vehicle, the this torque forces the front of the tow vehicle down.
I think you're seeing some magic. The torque on the ball is created by equal forces on the top and bottom therefore how can any force be transferred to the tow vehicle.
__________________
Byron & Anne enjoying the everyday Saturday thing.
Byron Kinnaman is offline   Reply With Quote
Old 07-28-2013, 01:36 PM   #56
Senior Member
 
Brian B-P's Avatar
 
Name: Brian
Trailer: Boler (B1700RGH) 1979
Alberta
Posts: 5,000
Quote:
Originally Posted by rabbit View Post
The elastomers and chains of the Anderson most certainly DO resist rotation of the coupler about the ball but in which plane? Vertical, horizontal. Both? If horizontal rotation is what's being restricted, I'd say the darn thing is a sway control and nothing more.
The friction between the cone and the head applies torque about the vertical axis, or if you prefer, controls motion in the horizontal plane... which is what is needed for sway control. As far as sway control is concerned, the chains and elastomeric springs are just to force the triangular plate, and thus the cone, to rotate with the trailer; as long as they don't go slack, the tension in them is irrelevant.

If the chains were in the same horizontal plane as the ball, then it would be nothing but a sway control (and that variation might be an interesting related product for Andersen); however, the chains pull several inches below the ball, so the rearward force on the plate, and corresponding forward force on the ball, combine to apply torque about the lateral horizontal axis to transfer load between axles - that's weight distribution. There is no movement required, but if there is movement about the axis you could call it movement in the longitudinal vertical plane. This has already been well described multiple times above - this is just my version, with the horizontal/vertical issue addressed.
__________________

__________________
1979 Boler B1700RGH, pulled by 2004 Toyota Sienna LE 2WD
Information is good. Lack of information is not so good, but misinformation is much worse. Check facts, and apply common sense liberally.
STATUS: No longer active in forum.
Brian B-P is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Front wheel drive, rear wheel drive, all wheel drive, and weight-distributing hitches Meg A. Towing, Hitching, Axles and Running Gear 14 04-26-2011 10:04 PM
weight distribution hitches Ian-Vicki Towing, Hitching, Axles and Running Gear 16 07-09-2007 03:47 PM
What Does a Weight-Distributing Hitch Do? Brian B-P General Chat 67 03-11-2007 07:41 PM
weight distributing hitch Legacy Posts Towing, Hitching, Axles and Running Gear 18 02-26-2003 06:36 PM
weight distributing hitch--clearance Derek Johnson Problem Solving | Owners Helping Owners 0 12-31-1969 07:00 PM

» Upcoming Events
No events scheduled in
the next 465 days.
» Virginia Campgrounds

Reviews provided by


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 03:57 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.