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TimTim wrote:
yobarr wrote:
TimTim wrote:

Ok so correct me if Im wrong.  I hook my caravan up and my rear suspension sinks.  The back springs sags because of the load on the tow ball, a bit like a spring scales. biggrin.

Then I attach my weight distribution hitch and the rear suspension rises so Im thinking that there must be less load on the rear suspension and therefore less load on the towball.   

I think I just got hit on the head with an apple 


 Sorry Tim, you too are confused as it is possible to tension a WDH high enough to actually lift the rear wheels of a car off the road. Levers ar work.

Now try and tell me that there is NO weight on the towball. Front axle weight of car will gain around 70% (+/-) while vans axle group will gain 30% (+/-) of the weight removed from the cars rear axle. Towball weight does not change. 
Main variables are wheelbase of car and towball overhang, or distance from rear axle of car to hitchpoint. Forward length of van also has an effect.
Somewhere I have a photo of such a situation, with rear wheels of car well clear of the road surface. Cheers

 


 Who said there was no load on the tow ball confuse.  Definitely wasnt me biggrin.  I do know what happens but it is a secret smile.


 Hi Tim, Sorry if you've misunderstood my reasons for saying "Now try and tell me that there is NO weight on the towball", but this is simply an extension of your comment ".. less load on the rear suspension and therefore less weight on the towball".

Surely this would suggest that NO weight on the rear suspension would mean NO weight on the towball?

I was simply using your thoughts to illustrate my point. Cheers



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Yobarr the pic of the bloke with his head in the sand is you.

You totally ignore all of the physics to cling to your claim that tow ball weight does not change.  

Physics says the weight contribution of the tug to a weighbridge read out is constant, regardless of any outside inputs due to being hitched to a van. Therefore hitched weight minus unhitched weight equals tow ball weight in all circumstances. End of story.

Put in print what you believe happens to the weight of van and tug when a WDH is tensioned if you do not agree with the above.

Alan

 



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Brenda and Alan wrote:

Yobarr the pic of the bloke with his head in the sand is you.

You totally ignore all of the physics to cling to your claim that tow ball weight does not change.  

Physics says the weight contribution of the tug to a weighbridge read out is constant, regardless of any outside inputs due to being hitched to a van. Therefore hitched weight minus unhitched weight equals tow ball weight in all circumstances. End of story.

Put in print what you believe happens to the weight of van and tug when a WDH is tensioned if you do not agree with the above.

Alan


Alan, are you sure that you're not simply being mischievous as it seems that you're disputing facts and data outlined by HR and many others who DO understand how a WDH works?

All you're achieving is creating total confusion for those members who are simply wanting to learn.

A WDH is NOT the magical cure-it-all device that many believe it to be, and buying a more suitable vehicle is a better option.

MANY times I have explained to you how you can use a weighbridge to show that your assertions are incorrect, and I do not propose to AGAIN print it all out for you. 

Perhaps when/if I am again in Victoria I can take you to a weighbridge to show what happens?

You are of course entitled to your opinion, no matter how misguided it may be, but I implore you not to taint information supplied worldwide, by experts, on the effects of using a WDH.

Have a great day. Cheers.



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Brenda and Alan wrote:

Yobarr the pic of the bloke with his head in the sand is you.

You totally ignore all of the physics to cling to your claim that tow ball weight does not change.  

Physics says the weight contribution of the tug to a weighbridge read out is constant, regardless of any outside inputs due to being hitched to a van. Therefore hitched weight minus unhitched weight equals tow ball weight in all circumstances. End of story.

Put in print what you believe happens to the weight of van and tug when a WDH is tensioned if you do not agree with the above.

Alan

 


 So Alan,

Do you disbelieve the statement in the link I provided? Here-  https://www.truckfriendly.com.au/weight-distribution-hitches-facts-and-fiction/

And in the following links-  

 

https://www.exploroz.com/forum/83621/tow-ball-weight-limit-with-wdh

https://www.carsguide.com.au/tradies/advice/top-eight-towing-myths-busted-73044  point 3

https://midlandtowbars.com.au/weight-distribution-hitch/not-everyone-needs-weight-distribution-hitch/   paragraph 6

https://www.gorv.com.au/using-a-weight-distribution-hitch-the-basics/#:~:text=Most%20WDHs%20involve%20heavy%20steel,redistribute%20weight%20across%20all%20axles.   1st paragraph

Many more on the www

Tony

 



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yobarr wrote:
MANY times I have explained to you (Brenda and Alan) how you can use a weighbridge to show that your assertions are incorrect, and I do not propose to AGAIN print it all out for you. 

 No. You can't use a weighbridge to prove/disprove towball weight changes. You can show how the WDH changes the weights imposed by each axle group. You can weigh the load imposed by the jockey wheel while disconnected (close enough to towball weight), but once connected that can no longer be weighed.

Eaglemax's analogy a few posts back about two men lifting the rear of the car does not relate to the WDH tensioning. There is no downward pressure on the drawbar imposed by the tension bars, and new load points are introduced with feet on the ground ... so the overall weight on the wheels would be reduced by the amount the men are lifting.

A WDH works by the net effect of the bars lifting the rear of the car vs the opposing load on the drawbar by the other end of the bars.

But as I have said before this whole argument about whether weight on the towball changes or not is irrelevant. That has no bearing on what the effect of the WDH is. So I am avoiding getting into that part of the discussion.



-- Edited by Are We Lost on Friday 13th of October 2023 01:01:33 PM

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Are We lost said

"Eaglemax's analogy a few posts back about two men lifting the rear of the car does not relate to the WDH tensioning. There is no downward pressure on the drawbar imposed by the tension bars, and new load points are introduced with feet on the ground ... so the overall weight on the wheels would be reduced by the amount the men are lifting."

Good pick up, thanks

As for relevance of effects on Towball weight, I wonder how many buy and use a WDH to lower the ball weight. Hence the relevance for some to object to the notion.
Tony

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Are We Lost wrote:
yobarr wrote:
MANY times I have explained to you (Brenda and Alan) how you can use a weighbridge to show that your assertions are incorrect, and I do not propose to AGAIN print it all out for you. 

 No. You can't use a weighbridge to prove/disprove towball weight changes. You can show how the WDH changes the weights imposed by each axle group. You can weigh the load imposed by the jockey wheel while disconnected (close enough to towball weight), but once connected that can no longer be weighed.

Eaglemax's analogy a few posts back about two men lifting the rear of the car does not relate to the WDH tensioning. There is no downward pressure on the drawbar imposed by the tension bars, and new load points are introduced with feet on the ground ... so the overall weight on the wheels would be reduced by the amount the men are lifting

A WDH works by the net effect of the bars lifting the rear of the car vs the opposing load on the drawbar by the other end of the bars.

But as I have said before this whole argument about whether weight on the towball changes or not is irrelevant. That has no bearing on what the effect of the WDH is. So I am avoiding getting into that part of the discussion.

 

 



-- Edited by Are We Lost on Friday 13th of October 2023 01:01:33 PM


 In simple terms the only ways of altering the "ball weight" of a caravan/trailer is to lengthen or shorten the tow bar or shift the axle/axle group forward or back or shift the weight (water tanks, fridge, goods and chattles ..) in the van forward or back. Caravan /trailer manufacturers use a combination of these methods to determine the final "ball weight" parameters of their product. 

If the "ball weight" overloads the rear axle of the tow vehicle then, in some cases, a Weight Distribution Hitch can be of benefit by distributing some of the excess weight from the rear axle to the steer axle (safer steering) and the remainder to the caravan/trailer axle/axles. Nothing else changes. 



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As for relevance of effects on Towball weight, I wonder how many buy and use a WDH to lower the ball weigh.. Hence the relevance for some to object to the notion.
Tony


 From my experience, all users of a WDH have this belief. And don't they get most indignant when I point out, in the diplomatic manner that  I'm known for, that they've either been misled by commission-based salesmen or they have no understanding of physics. 

Either way, once I actually demonstrate to them how a WDH works they invariably are grateful, and most thankful in the main.

Occasionally we get a member of the "Hole in the Sand brigade" who pigheadedly argues the point, the level of his inability to accept fact being directly related to how many stubbies he's drunk. 

"You can lead a horse to water, but you can't make it drink." Some peoples' biggest asset is their ignorance. Cheers



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I use my WDH to INCREASE my LEAGAL ball weight towing capacity. In my case of with my KK Jeep, without a WDH I can tow 160kg ball weight and 1600kg van. With a WDH, I can legally and safely tow with 227kg ball weight.

My WDH hitch INCREASES my legal towing ball weight from 160kg to 227kg. And bonus, van towing capacity goes from 1600kg to 2270kg towing capacity with a WDH.

Everything else is bollocks and rubbish to me, personal opinions on this is irrelevant.

I'm legal with my 1800kg ATM van with 180kg ball weight with a WDH because JEEP says so, in the manual.

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Cube wrote:

I use my WDH to INCREASE my LEAGAL ball weight towing capacity. In my case of with my KK Jeep, without a WDH I can tow 160kg ball weight and 1600kg van. With a WDH, I can legally and safely tow with 227kg ball weight.

My WDH hitch INCREASES my legal towing ball weight from 160kg to 227kg. And bonus, van towing capacity goes from 1600kg to 2270kg towing capacity with a WDH.

Everything else is bollocks and rubbish to me, personal opinions on this is irrelevant.

I'm legal with my 1800kg ATM van with 180kg ball weight with a WDH because JEEP says so, in the manual.


 Not sure what you're on about by claiming that your WDH increases ball weight, as no such thing can, or does happen.

What the WDH does, I suspect, is allow you to APPLY a 227kg ball weight because said WDH takes enough weight OFF the car's rear AXLE to allow a 227kg ball weight, the generally accepted 10% of ATM towball weight. (160kg is 10% of 1600kg)

Jeeps generally have a pathetically low rear axle carrying capacity, under 1700kg I believe, and using the WDH takes weight OFF that axle, ALLOWING a higher towball weight to be used, NOT physically increasing it.

Again, the WDH ALLOWS a higher towball weight, but does NOT physically increase that towball weight.

Hope this helps? Cheers.

P.S A WDH does NOT change towball weight. Never has. Never will.



-- Edited by yobarr on Friday 13th of October 2023 07:52:41 PM

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Cube said ", I can legally and safely tow with 227kg ball weight" Just saying Cube, towball weight is not a legal requirement. You'll never be prosecuted for a ball weight too high or too low. The ideal ball weight is another topic. Tony

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Yobarr and KJB.  The axle weights on the tug are determined by the only other weight imput  onto the tug (towball weight) and reflect exactly that. No magic, no altering gravity, no mass trandference.

Change the tow ball weight imput and you change the axle weights in strict accordance with the ratio of towball overhang to wheel base.

It is that simple.

Yobarr.  In order to accommodate your belief it is inherrent that either gravity is altered or mass is transfered from tug to van.

 As usual when pinned down you don't respond, so I ask again which do you think changes, gravity or mass. If you cant come back with a definte answer to this question I suggest you throw in the towel.

Alan



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yobarr wrote:
Cube wrote:

I use my WDH to INCREASE my LEAGAL ball weight towing capacity. In my case of with my KK Jeep, without a WDH I can tow 160kg ball weight and 1600kg van. With a WDH, I can legally and safely tow with 227kg ball weight.

My WDH hitch INCREASES my legal towing ball weight from 160kg to 227kg. And bonus, van towing capacity goes from 1600kg to 2270kg towing capacity with a WDH.

Everything else is bollocks and rubbish to me, personal opinions on this is irrelevant.

I'm legal with my 1800kg ATM van with 180kg ball weight with a WDH because JEEP says so, in the manual.


 Not sure what you're on about by claiming that your WDH increases ball weight, as no such thing can, or does happen.

Hope this helps? Cheers.

P.S A WDH does NOT change towball weight. Never has. Never will.



-- Edited by yobarr on Friday 13th of October 2023 07:52:41 PM


Not sure what you're drinking tonight, but i'll have a few, even with you maybe some day.

I never claimed my WDH made my van ball weight magically increase by attaching a WDH to my tug.  You literally mis read or mis interpreted my post, made that assertion up in your head, then applied that to me as a fact of matter, and even put it in writing that I SAID that rubbish, you just made up in your head.  Sorry dude, real life is a little more different in the real world than that, especially when put in writing as in a forum such as this where just above, is the actual text. 

Respectfully, just stop that.

My WDH allows me according to JEEP manual,  to magically increase my van ball weight I can tow, from 160kg to 227 kg.  That was very clear and concise as above.  You just misread it, probably by skimming my post with a negative frame of mind.  NOT, as you asserted I said,  magically increases the van ball weight by attaching a WDH to my JEEP.  That's just retarded thinking.  In fact, i say so retarded, one should not be driving on the road if that was ones thinking.

 



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Eaglemax wrote:

Cube said ", I can legally and safely tow with 227kg ball weight" Just saying Cube, towball weight is not a legal requirement. You'll never be prosecuted for a ball weight too high or too low. The ideal ball weight is another topic. Tony


 Good point Tony, I'm coming from a insurable angle, not so clear so yes my error sorry,  but insurance wise, im uninsured if I go over tug manual specs in ball weight or towing weight as is everyone else.  Make no mistake, a insurance company will weight everything to get out of a claim.  So, uninsured means no insurance to pay legal fees or damages to someone if a accident occurs.

I am unsure to what any local or federal consequences of things would be if one is above manufacture towing capacity's in a fatal accident (apart from no insurance to pay compensation and legal fees).  I would expect prison time would be involved if in error and death was a consequence of that.  Having ones house or other assets sold to compensate a accident (no insurance to pay a multi million dollar compensation fine and legal expenses etc), especially with ones own family or kids involved, is a sentence in itself.

I've read some horror stories where a driver was done for wrongful or negligent death of others for over weight vans, which means over weight ball weight too I suppose, and lost everything including house, job, kids, wife and so on due to going to the slammer and everything was sold to pay debts.  I'm pretty keen for that never to happen to my family.

Think I just found my tonight's rabbit hole - 'can you be be sued into oblivion for over ball weight or van weight in a death or any accident'.

So by 'legal' I just refine it to 'doing everything right to cover all your bases/family asses' so you're covered financially if SHTF.

 



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Brenda and Alan wrote:

Yobarr and KJB.  The axle weights on the tug are determined by the only other weight imput  onto the tug (towball weight) and reflect exactly that. No magic, no altering gravity, no mass trandference.

Change the tow ball weight imput and you change the axle weights in strict accordance with the ratio of towball overhang to wheel base.

It is that simple.

Yobarr.  In order to accommodate your belief it is inherrent that either gravity is altered or mass is transferred from CAR to van. (Tugs drift around the harbour)

 As usual when pinned down you don't respond, so I ask again which do you think changes, gravity or mass. If you cant come back with a definte answer to this question I suggest you throw in the towel.

Alan


 Alan, again I will suggest that you're simply being mischievous?   Can I suggest that you drive your car and van, with the untensioned WDH in place, to a local weighbridge.

Drive right across the weighbridge until only the van's wheels are on the weighbridge. Note the weight.

Now get out of car and tension WDH as much as you can, simply for this exercise. Note the weight. 

Deduct first weight from second weight to show how much weight your WDH has added to your van's axle group. Simple.

Towball weight does not change, but total weight of van (ATM if you like) will have increased because the GTM has increased.

Note:- This is a much-simplified explanation of the procedure, but I hope that it is simple enough for you to understand?

Please refer to one of the many detailed posts I've previously made explaining the full procedure, as I feel that I'm talking to a wall. 

When the designers and manufacturers, along with myriad experts in weights and dynamics, state emphatically  that a WDH DOES NOT CHANGE TOWBALL WEIGHT it is difficult to understand your stance. 

I am at a loss to understand how you persist with your own convoluted 'theories'.

Have a great weekend. Cheers

P.S How to waste BIG money.

0B0F2AE7-9E97-488B-95D8-275DA992C497.png

 

 



-- Edited by yobarr on Friday 13th of October 2023 09:55:53 PM

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Yobarr, that is twice tonight (as well as earlier in this thread) that you have misunderstood what others are saying. First Cube, and now (Brenda and) Alan.

I have not seen any comments on here from anyone who does not understand the weight transfer by using a WDH.



 



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Cube wrote:
Eaglemax wrote:

Cube said ", I can legally and safely tow with 227kg ball weight" Just saying Cube, towball weight is not a legal requirement. You'll never be prosecuted for a ball weight too high or too low. The ideal ball weight is another topic. Tony


 Good point Tony, I'm coming from a insurable angle, not so clear so yes my error sorry,  but insurance wise, im uninsured if I go over tug manual specs in ball weight or towing weight as is everyone else.  Make no mistake, a insurance company will weight everything to get out of a claim.  So, uninsured means no insurance to pay legal fees or damages to someone if a accident occurs.

I am unsure to what any local or federal consequences of things would be if one is above manufacture towing capacity's in a fatal accident (apart from no insurance to pay compensation and legal fees).  I would expect prison time would be involved if in error and death was a consequence of that.  Having ones house or other assets sold to compensate a accident (no insurance to pay a multi million dollar compensation fine and legal expenses etc), especially with ones own family or kids involved, is a sentence in itself.

I've read some horror stories where a driver was done for wrongful or negligent death of others for over weight vans, which means over weight ball weight too I suppose, and lost everything including house, job, kids, wife and so on due to going to the slammer and everything was sold to pay debts.  I'm pretty keen for that never to happen to my family.

Think I just found my tonight's rabbit hole - 'can you be be sued into oblivion for over ball weight or van weight in a death or any accident'.

So by 'legal' I just refine it to 'doing everything right to cover all your bases/family asses' so you're covered financially if SHTF.

 


 Hi Cube,

I have been in quasi law enforcement where rules and regs were my field and also built 2 caravans to Australian Standards. That gives me some idea on legalities but I welcome correction as we arent all perfect. So below I'll try to answer your questions- 

 Good point Tony, I'm coming from a insurable angle, not so clear so yes my error sorry,  but insurance wise, im uninsured if I go over tug manual specs in ball weight (yes, maximum towball weight on the compliance plate on the caravan) or towing weight (yes ATM) as is everyone else.  Make no mistake, a insurance company will weight everything to get out of a claim (yes but towball percentage - weight to ATM is not a legal requirement).  So, uninsured means no insurance to pay legal fees or damages to someone if a accident occurs. (So, dont overload the caravan beyond ATM and dont load the van so your maximum towball weight is more than stated by the manufacturer. Dont exceed towbar limits, tug GVM, rear axle limit and GCM and towball weight is part of your GVM)

I am unsure to what any local or federal consequences of things would be if one is above manufacture towing capacity's in a fatal accident (apart from no insurance to pay compensation and legal fees).  I would expect prison time would be involved(unlikely as up to 80% of caravans are towed illegally but still...) if in error and death was a consequence of that.  Having ones house or other assets sold to compensate a accident (no insurance to pay a multi million dollar compensation fine and legal expenses etc), especially with ones own family or kids involved, is a sentence in itself. (this is all serious however negligence has to be proven in court. We are talking here about towball weight changing when you use a WDH, it doesnt, So set your towball weight before you hitch up using scales, move your load to get the best towball weight then if you want to use a WDH, hitch up and use it to level the tug.)

I've read some horror stories where a driver was done for wrongful or negligent death of others for over weight vans, which means over weight ball weight too I suppose (not in all cases), and lost everything including house, job, kids, wife and so on due to going to the slammer and everything was sold to pay debts.  I'm pretty keen for that never to happen to my family.

Think I just found my tonight's rabbit hole - 'can you be be sued into oblivion for over ball weight or van weight in a death or any accident'. (yes, if found to be negligent so be legal. If you want to, provide all your vehicle details and ask here on a new topic and we can go through it with you)

So by 'legal' I just refine it to 'doing everything right to cover all your bases/family asses' so you're covered financially if SHTF.(correct, this is what the forum is for- to help some be legal. Ask away, provide your weights, towcar details, van detail and you will get a correct answer.)

 

I will correct myself " You'll never be prosecuted for a ball weight too high or too low." That's incorrect, a ball weight over the compliance plate maximum is illegal, the percentage of towball to ATM is not a legal requirement but be safe and seek 10% if possible unless manufacturer states otherwise)  

Weights are complex for those that havent got a grip on them so we were all in your situation once.

Tony

 



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yobarr wrote:
Brenda and Alan wrote:

Yobarr and KJB.  The axle weights on the tug are determined by the only other weight imput  onto the tug (towball weight) and reflect exactly that. No magic, no altering gravity, no mass trandference.

Change the tow ball weight imput and you change the axle weights in strict accordance with the ratio of towball overhang to wheel base.

It is that simple.

 

?????????

 

Yobarr.  In order to accommodate your belief it is inherrent that either gravity is altered or mass is transferred from CAR to van. (Tugs drift around the harbour)

 As usual when pinned down you don't respond, so I ask again which do you think changes, gravity or mass. If you cant come back with a definte answer to this question I suggest you throw in the towel.

Alan


 Alan, again I will suggest that you're simply being mischievous?   Can I suggest that you drive your car and van, with the untensioned WDH in place, to a local weighbridge.

Drive right across the weighbridge until only the van's wheels are on the weighbridge. Note the weight.

Now get out of car and tension WDH as much as you can, simply for this exercise. Note the weight. 

Deduct first weight from second weight to show how much weight your WDH has added to your van's axle group. Simple.

Towball weight does not change, but total weight of van (ATM if you like) will have increased because the GTM has increased.

Note:- This is a much-simplified explanation of the procedure, but I hope that it is simple enough for you to understand?

Please refer to one of the many detailed posts I've previously made explaining the full procedure, as I feel that I'm talking to a wall. 

When the designers and manufacturers, along with myriad experts in weights and dynamics, state emphatically  that a WDH DOES NOT CHANGE TOWBALL WEIGHT it is difficult to understand your stance. 

I am at a loss to understand how you persist with your own convoluted 'theories'.

Have a great weekend. Cheers

P.S How to waste BIG money.

0B0F2AE7-9E97-488B-95D8-275DA992C497.png

 

 



-- Edited by yobarr on Friday 13th of October 2023 09:55:53 PM


 



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In this hypothetical example, what is my towball weight? According to Yobarr if you said 250kg you would be wrong.

Weighbridge.jpg

 



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Are We Lost wrote:

In this hypothetical example, what is my towball weight? According to Yobarr if you said 250kg you would be wrong.

Weighbridge.jpg

 


 Usually I can decipher even the most convoluted 'reasoning', but you've got me stumped here! 

How on earth you've decided that my advice would give a  result different from the obvious 250kg towball weight, in the above illustration, is beyond me. Please explain. Cheers.



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yobarr wrote:
How on earth you've decided that my advice would give a  result different from the obvious 250kg towball weight, in the above illustration, is beyond me. Please explain. Cheers.

The fishing is good today.

I must have forgotten to mention that the image is with a WDH fitted.

In this hypothetical example I also had more readings at the weighbridge. The weights before WDH tension were:

Front axle:   1030

Rear axle:     1750

Total:          2780

Van wheels:  2220

Ball weight:   280 (measured jockey wheel while disconnected).

Weighbridge again.jpg

 

 The van can't change its weight. There are only two points that matter ..... the wheels and the towball. So if there is 30kg more weight on its wheels, there must be 30kg less on the towball.

 

 



-- Edited by Are We Lost on Saturday 14th of October 2023 04:00:47 PM

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Are We Lost wrote:
yobarr wrote:
How on earth you've decided that my advice would give a  result different from the obvious 250kg towball weight, in the above illustration, is beyond me. Please explain. Cheers.

The fishing is good today.

I must have forgotten to mention that the image is with a WDH fitted.

In this hypothetical example I also had more readings at the weighbridge. The weights before WDH tension were:

Front axle:   1030

Rear axle:     1750

Total:          2780

Van wheels:  2220

Ball weight:   280 (measured jockey wheel while disconnected).

Weighbridge again.jpg

 

 The van can't change its weight. So if there is 30kg more weight on its wheels, there must be 30kg less on the towball.


 Unfortunately you appear to be so lost in the wilderness that you're likely to meet Alan.

Busy travelling today, but I'll have look later.Cheers



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Are We Lost wrote:
yobarr wrote:
How on earth you've decided that my advice would give a  result different from the obvious 250kg towball weight, in the above illustration, is beyond me. Please explain. Cheers.

The fishing is good today.

I must have forgotten to mention that the image is with a WDH fitted.

In this hypothetical example I also had more readings at the weighbridge. The weights before WDH tension were:

Front axle:   1030

Rear axle:     1750

Total:          2780

Van wheels:  2220

Ball weight:   280 (measured jockey wheel while disconnected).

Weighbridge again.jpg

 

 The van can't change its weight. There are only two points that matter ..... the wheels and the towball. So if there is 30kg more weight on its wheels, there must be 30kg less on the towball.


 Hi Stephen, There is no need to play games ( I refer to "must have forgotten to mention that the image is with a WDH fitted"), but thankyou for confirming that fact, because it was the first variable that I thought of when viewing your pretty picture.

Perhaps you can help me, but I don't understand what your pretty picture is supposed to illustrate?

You should by now understand that a WDH removes weight from the car's REAR AXLE and distributes around 70% of that weight to the car's front axle, while the remaing 30% is distributed to the van's axle group.

This is clearly illustrated in your pretty pictures, where weight on wheels (GCM?) is constant at 5000kg. 

Before you tension your WDH you have front axle at 1030kg, rear axle at 1750kg and van's axle group at 2220kg.

Thus you have a vehicle unit with 5000kg on its wheels. (Car 2780kg and van 2220kg)

After you tension your WDH you have front axle at 1100kg (70kg gain) rear axle at 1650kg (100kg loss) and van's axle group at 2250kg (30kg gain).

Thus you still have a vehicle unit with 5000kg on its wheels.  (Car 2750kg and van 2250kg)

 

Your car weighs 30kg less ( 2750kg) than it did before WDH was tensioned,(2780kg) while caravan weighs 30kg more (2250kg) than it did before WDH was tensioned. (2220kg). Simple stuff.

Towball weight could have been 15kg (or 5 ton figuratively speaking ) at the outset, but it still would be 15kg (or 5 ton)at finish.

A WDH does NOT change towball weight.

Never has.  Never will.    .

You no doubt will have observed that, coincidentally, of the 100kg removed from the car's rear axle, 70kg (70%) has been distributed to the car's front axle, while 30kg (30%) has been distributed to the van's axle group.

Towball weight has not changed.

Unwittingly perhaps, you've shown exactly what I've been saying for eons.

As always, my primary objective is to help people understand their weights, so I hope that this helps you? Cheers

 



-- Edited by yobarr on Sunday 15th of October 2023 12:27:31 AM

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Yobarr, most of your post appears to be explaining the weight distribution again. Don't forget it was me the developed those figures.

I was staying out of the discussion on whether towball weight changes or not because it is irrelevant. But I got sucked in again when you continued to propose using a weighbridge to prove it.



-- Edited by Are We Lost on Sunday 15th of October 2023 09:31:33 AM

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Are We Lost wrote:

Yobarr, most of your post appears to be explaining the weight distribution again. Don't forget it was me the developed those figures.

I was staying out of the discussion on whether towball weight changes or not because it is irrelevant. But I got sucked in again when you continued to propose using a weighbridge to prove it.



-- Edited by Are We Lost on Sunday 15th of October 2023 09:31:33 AM


 I think change in towball weight is relevant now that it is the main topic. Just read the last 6 posts and it leads to nowhere.

Are you suggesting the 30kg extra weight on the van wheels is caused by the spring effect of the WDH? If thats the case hypothetically if you had a drawbar only no van and a towbars only no car hitched together then tried to tension a WDH the hitch would want to go towards the ground thereby adding weight? 

I'm good at math but this is not easy physics for some.

Tony



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What I meant was that it is irrelevant whether towball weight changes or not. That is internal to the system.

What is relevant is the outcome, being changed weight on the wheels. Those weights definitely can be measured at a weigbridge. They are what Yobarr refers to and we agree on that, although we differ on the benefits.

This subject has come up before and becomes more technical with discussion on the difference between weight and mass, rotational forces, using newton metres as a measurement and more. Without getting into it, I suggest you look up the different types of levers. In the case of that original photo it is similar to many WDH designs, (with the Andersen Hitch being a notable exception). It is using a second class lever with the fulcrum at the front wheels (like a wheelbarrow). This is opposed by ....

No I am not going there. Done.



-- Edited by Are We Lost on Sunday 15th of October 2023 11:28:46 AM

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I am showing some links to information about some Physics calculations for others to refer to some posts that I put in to "WDH again" on 13th and 14th May 2023.

https://thegreynomads.activeboard.com/t69403250/wdh-again/?sort=oldestFirst&page=3#comment-69434647

https://thegreynomads.activeboard.com/t69403250/wdh-again/?sort=oldestFirst&page=4#comment-69437698

 

Around that time, there were a few questions about my calculations to which I gave some clarifications.

I will allow the reader to interpret for themselves whether the tow ball weight changes.

Or maybe it is the reaction force on the tow ball that changes when the WDH is tensioned?  We know that the reactions of the ground on the axles of the tow vehicle and caravan change when the WDH is tensioned. 

I will leave that as food for thought.



-- Edited by watsea on Sunday 15th of October 2023 11:55:52 AM



-- Edited by watsea on Sunday 15th of October 2023 11:56:54 AM



-- Edited by watsea on Sunday 15th of October 2023 12:06:50 PM

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yobarr wrote:
Brenda and Alan wrote:

Yobarr and KJB.  The axle weights on the tug are determined by the only other weight imput  onto the tug (towball weight) and reflect exactly that. No magic, no altering gravity, no mass trandference.

Change the tow ball weight imput and you change the axle weights in strict accordance with the ratio of towball overhang to wheel base.

It is that simple.

Yobarr.  In order to accommodate your belief it is inherrent that either gravity is altered or mass is transferred from CAR to van. (Tugs drift around the harbour)

 As usual when pinned down you don't respond, so I ask again which do you think changes, gravity or mass. If you cant come back with a definte answer to this question I suggest you throw in the towel.

Alan


 

Towball weight does not change, but total weight of van (ATM if you like) will have increased because the GTM has increased. 

--------------------------------------------------------------------------------------------------------------------------------------------------

Yobarr  Total weight of the van CAN'T change unless gravity or its mass changes.  Its weight is given by the equation F=ma .

Force, in this case weight equals mass times the acceleration due to gravity. Mass and weight are two different physical entities,

 



-- Edited by Brenda and Alan on Sunday 15th of October 2023 04:18:17 PM

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Yobarr   

Your reply to Are We Lost regarding his diagram with and without a WDH shows your total lack of understanding or basic physical principals. The car cannot weigh 30 Kgwt less unless its mass is reduced by 30 KG, likewise with  the van a 30 Kgwt increase would require a 30 Kg increase in mass.

Weight and mass are different physical quantities and are not interchangeable.

As to not understanding it, I find it shows exactly what occurs with a WDH with the weight contribution of both car and van constant.

Alan

 



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There are non so blind as those that will not see, except for those that cherry pick numbers and ignore the rest.

The truth is out there, but those with WD Hitches seem unable to see it....

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