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Post Info TOPIC: WDH, Air Bags and/or Increased rear Spring Capacity.


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Just remember that the mass of sand is the force of gravity on each molecule in the sand = weight of the sand in the bucket. There are other forces acting here, such as the rotational forces exerted by the springs of the WDH, while measured as weight, it has no mass, it is just leverage exerted about fulcrum points, such as the rear and front axles.

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Are We Lost wrote:

C'mon you two. Like two school kids seeing who can reach further up the wall in the latrine.

Picking up on an earlier post, Oldbloke said .
"Since the example you refer to is fitted with a fully adjusted WDH the ball weight is distributed to the front axles of the tow vehicle and the van axles it is not unreasonable to expect 0 or near to 0 on the ball. It is an example. Or are you unable to read a simple set of tables. Too simple for you. Eh."

Sorry Oldbloke, its you who has misunderstood the chart. The towball weight is still 220kg, not 0. The chart just does not show it.

Thanks Stephen,for stating the obvious.Many "newbies" have no knowledge of WDH,and the rubbish sprouted by Neil would serve only to totally confuse them.Always I try to make things as easily understood as possible for newbies,and others,but sometimes my efforts are sabotaged by well-meaning members who are simply ignorant of the facts.This topic has been covered,in detail,many times on the forum.


What the chart is showing is the weight on the wheels. Only the first line shows towball weight because that is on the jockey wheel. After the van is connected, the towball weight is ignored, and is certainly not zero and should never be zero. But while Yobarr noted that zero weight on the ball was a ludicrous situation, he did not look further.


And Yobarr is correct that the ball weight does not change with a WDH, which is as stated by HR

"Ball weight does not change with a WDH,which is stated by HR" 


Im sure others will be confused with that chart as well. Did that come from Hayman Reese?


Also, I believe the example shows a WDH that has been over-tensioned. From a relatively modest towball weight of 220kg, they have taken 290kg off the rear axle, and put 230 on the front. A bit excessive in my opinion.

Certainly over-tensioned,with massive amounts of oversteer being the result.


By the way . Its spelt Hayman Reese.



-- Edited by Are We Lost on Saturday 18th of December 2021 11:35:05 AM


 



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Sooo, if the 220 was indicated on the TB your argument would then be that it doesnt add up. Or the weight is not distributed. You can't have it both ways. The weight can only be in one place at a time.
If the weight is on the axles, it can't be on the TB.



-- Edited by oldbloke on Saturday 18th of December 2021 11:49:18 AM

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oldbloke wrote:

......
If the weight is on the axles, it can't be on the TB.



-- Edited by oldbloke on Saturday 18th of December 2021 11:49:18 AM


Of course it can.

If you stood on the connected drawbar right over the towball, you would add (say) 100kg to the towball load. Would the weight on the wheels increase? Of course. So your weight has added to the towball load, which is then spread accross all the wheels.

If you now tensioned the WDH, your weight is still 100kg on the towball, and the total weight across all wheels combined is the same as before. The weight is now just distributed differently.

 



-- Edited by Are We Lost on Saturday 18th of December 2021 12:29:45 PM

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Are We Lost wrote:
oldbloke wrote:

......
If the weight is on the axles, it can't be on the TB.



-- Edited by oldbloke on Saturday 18th of December 2021 11:49:18 AM


Of course it can.

If you stood on the connected drawbar right over the towball, you would add (say) 100kg to the towball load. Would the weight on the wheels increase? Of course. So your weight has added to the towball load, which is then spread accross all the wheels.

If you now tensioned the WDH, your weight is still 100kg on the towball, and the total weight across all wheels combined is the same as before. The weight is now just distributed differently.

 



-- Edited by Are We Lost on Saturday 18th of December 2021 12:29:45 PM


 Without becoming pedantic over possible minor variations in movement/angles/levels etc. your explanation  of one part of the  WDH  subject is nice ,simple and easy to understand - hopefully, for all on here who read it.   KB



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Are We Lost wrote:
oldbloke wrote:l

......
If the weight is on the axles, it can't be on the TB.


Of course it can.

If you stood on the connected drawbar right over the towball, you would add (say) 100kg to the towball load. Would the weight on the wheels increase? Of course. So your weight has added to the towball load, which is then spread accross all the wheels.

If you now tensioned the WDH, your weight is still 100kg on the towball, and the total weight across all wheels combined is the same as before. The weight is now just distributed differently.


 Great explanation Stephen,which should be easily understood by even the most challenged.Thankyou.It never ceases to amaze me how some people can be confused by something so simple,but pigheadedly refuse to acccept facts published by Hayman Reese,and supplied by those of us who do have knowledge . When a newbie,or even a current member wants help with a WDH,the last thing he needs is to have the supplied facts disputed,on the forum by someone who doesn't appear to have any real understanding of the physics involved. The manufacturer of the product being discussed says that a WDH does NOT change towball weight.Never has. Never will.Cheers

P.S Did the WDH cause this,or was it the bags of sand in the boot? This may help those who do not understand that a WDH puts downforce onto a van's axle group,often around 30% of the weight removed from the car's REAR AXLE.This is dependent on wheelbase of car,TBO,and forward length  of the van.Cheers

 

CC4FD786-F585-4374-95EC-30F90E53188C.png

 

 



-- Edited by yobarr on Saturday 18th of December 2021 01:41:05 PM

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KJB wrote:
Are We Lost wrote:
oldbloke wrote:

......
If the weight is on the axles, it can't be on the TB.


Of course it can.

If you stood on the connected drawbar right over the towball, you would add (say) 100kg to the towball load. Would the weight on the wheels increase? Of course. So your weight has added to the towball load, which is then spread accross all the wheels.

If you now tensioned the WDH, your weight is still 100kg on the towball, and the total weight across all wheels combined is the same as before. The weight is now just distributed differently.


 Without becoming pedantic over possible minor variations in movement/angles/levels etc. your explanation  of one part of the  WDH  subject is nice ,simple and easy to understand - hopefully, for all on here who read it.   KB


        Well said Kerry.Stephen's example should be easily understood by anyone who is conscious.Cheers 



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To further clarify.

HR says the TBW does not change. I agree. We all agree it is still there. Weight can't change in this case.
HR says the TBW is distributed and transferred to van and front axles. (Mostly) I agree
The weight is transfer through the levers and chassis to other axles.


So, HR "indicate" "0" in the "box". Why? Otherwise the combination weight would magically increase by 220kg. This would be more confusing. Particularly since scales the weight is now transferred to the road via at the axles/wheels. As I've said in the past, it's a graphic to show how it works. To clarify the "0", they state it does not change. For just a few they think HR are being deceptive or confusing. I don't agree I understand it is about where it is transferred to and measured.

I do not consider this confusing or deceptive. It's just where it is measured. WDH do not increase the combination, and that is what some here seem to be saying. The only increase is the 30kg or so the WDH weighs.

One more point. When the van is not hitched to the car it is sitting on the jockey, a point at which a scale can be used. (220kg is indicated) When hitched the jockey would not be on, so you are unable to use a scale under the hitch.

Cheers

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oldbloke wrote:

To further clarify.

HR says the TBW does not change. I agree. We all agree it is still there. Weight can't change in this case.
HR says the TBW is distributed and transferred to van and front axles. (Mostly) I agree
The weight is transfer through the levers and chassis to other axles.


So, HR "indicate" "0" in the "box". Why? Otherwise the combination weight would magically increase by 220kg. This would be more confusing. Particularly since scales the weight is now transferred to the road via at the axles/wheels. As I've said in the past, it's a graphic to show how it works. To clarify the "0", they state it does not change. For just a few they think HR are being deceptive or confusing. I don't agree I understand it is about where it is transferred to and measured.

Can't recall anyone suggesting that HR are being "deceptive or confusing",but you may have felt that that was the case.All I have ever said is that I felt HR were simply trying to help beginners by keeping things as simple as possible.

I do not consider this confusing or deceptive. It's just where it is measured. WDH do not increase the combination, and that is what some here seem to be saying.The only increase is the 30kg or so the WDH weighs.

Don't know how you determined that anyone claims that a WDH increases the combination,as that has never even been suggested,nevermind claimed.

One more point. When the van is not hitched to the car it is sitting on the jockey, a point at which a scale can be used. (220kg is indicated) When hitched the jockey would not be on, so you are unable to use a scale under the hitch.

Cheers


 Well done Neil,as it seems you've seen the light at last.Well done! The increase in the weights on the axles tells the story.The van obviously has non-loadsharing axles as,when the van was hooked up to the car,the weight on the lead axle increased by 40kg because the front of the van (towball) was lower when the car's springs settled.THEN,when the WDH was tensioned,the rear axle of the van gained 70kg while the lead axle lost 10kg,meaning that the WDH has transferred a nett 60kg from the car's REAR AXLE to the van's axle group,thus increasing both the GTM and total weight of van.(ATM if you wish).As an aside,there has been too much weight removed from the rear axle of the car,as evidenced by 110kg added to the car's front axle and the unequal weights on the axles of the non-loadsharing caravan suspension.The fact that the rear of the car dropped only 10mm from its unladen weight is a nonsense,but once again may have been done to help novices.Great to see,however,that you seem to have finally sorted out in your mind how a WDH works.Cheers



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So, you finally understand what I have been trying to explain to you yobarr. Good.

Just can't admit that many times you said the graphic should indicate 220kg where it shows 0. Poor memory eh.



-- Edited by oldbloke on Sunday 19th of December 2021 04:29:09 AM

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A simple explanation.
Put a 220kg concrete block on the drawbar of the unhitched tug. The effect will impose weight on the rear axle and remove some from the front.
Now put a jack under the drawbar and raise it. This will transfer the weight from the rear axle to the front but the 220kg block is still on the drawbar.

Fitting a WDH does not change the ball download it simply transfers weight from the rear axle to the front and a small percentage to the van wheels.


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oldbloke wrote:

So, you finally understand what I have been trying to explain to you yobarr. Good.

Just can't admit that many times you said the graphic should indicate 220kg where it shows 0. Poor memory eh.


Time to give up Neil,and admit that you're wrong. Have you ever considered a career in Politics? Referring to your pathetic attempts at ducking, weaving and manipulating the truth in an effort to avoid admitting you're wrong.Seems that you still can't understand that the 220kg is the towball weight and that a WDH doesn't change towball weight,so the 220kg is still there.Got it? In a final effort to help you understand,could I ask you to refer to Montie's post above,where the process is succintly explained. Cheers



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It would be great to see a set of scales set on the tow ball. Then place the hitch on the scales Then WDH applied. (Maybe with a light trailer as an example.) Simples. Cheers Stewart .

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Stewart wrote:

It would be great to see a set of scales set on the tow ball. Then place the hitch on the scales Then WDH applied. (Maybe with a light trailer as an example.) Simples. Cheers Stewart .


 Just set up  the tow bar (car and caravan )  with the WDH in place and tensioned  , and the Cup resting on the Tongue  without the Ball  -  if there is no weight on the Tongue  you should be able to lift the Cup (incl. the "A" bar of the van ) with one finger ..........  Best of Luck!        KB



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Hahaha. Nice I like it.

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yobarr wrote:
oldbloke wrote:

So, you finally understand what I have been trying to explain to you yobarr. Good.

Just can't admit that many times you said the graphic should indicate 220kg where it shows 0. Poor memory eh.


Time to give up Neil,and admit that you're wrong. Have you ever considered a career in Politics? Referring to your pathetic attempts at ducking, weaving and manipulating the truth in an effort to avoid admitting you're wrong.Seems that you still can't understand that the 220kg is the towball weight and that a WDH doesn't change towball weight,so the 220kg is still there.Got it? In a final effort to help you understand,could I ask you to refer to Montie's post above,where the process is succintly explained. Cheers


 Your an idiot. And likely a troll.

"WDH doesn't change towball weight"   

Pls done verbena me, I repeatedly said it was distributed, and transferred to the axles.

How many times did you say the document was wrong. Truck loads. You know, the never,  never, never sh1t. In this case it was appropriate to show 0 TBW.  You have realised it was correct all along and to change the 0 TBW would have changed the GCM. But you didn't realise that till I spelt it out.  It was never a technical document like you try to make out, just a guide.  And BTW, add some spaces and paragraphs  in future pls.



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oldbloke wrote:
yobarr wrote:
oldbloke wrote:

So, you finally understand what I have been trying to explain to you yobarr. Good.

Just can't admit that many times you said the graphic should indicate 220kg where it shows 0. Poor memory eh.


Time to give up Neil,and admit that you're wrong. Have you ever considered a career in Politics? Referring to your pathetic attempts at ducking, weaving and manipulating the truth in an effort to avoid admitting you're wrong.Seems that you still can't understand that the 220kg is the towball weight and that a WDH doesn't change towball weight,so the 220kg is still there.Got it? In a final effort to help you understand,could I ask you to refer to Montie's post above,where the process is succintly explained. Cheers


 Your an idiot. And likely a troll.

"WDH doesn't change towball weight"   

Pls done verbena me, I repeatedly said it was distributed, and transferred to the axles.

How many times did you say the document was wrong. Truck loads. You know, the never,  never, never sh1t. In this case it was appropriate to show 0 TBW.  You have realised it was correct all along and to change the 0 TBW would have changed the GCM. But you didn't realise that till I spelt it out.  It was never a technical document like you try to make out, just a guide.  And BTW, add some spaces and paragraphs  in future pls.


Verbena? In to horticulture now,are we? Have a great day.Cheers

 

 B684A1E9-FD7E-413B-A7CB-E87B793D1912.png

 

 



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iana wrote:

Well folks, to throw a spanner in the works, my thoughts are, is that a WDH does alter the downward force of the trailer coupling. It will depend entirely on how much the rear of the tow vehicle sags when the trailer is coupled, to when the WDH is adjusted so that the trailer is level.
Any rotation about the central axis will change the center of gravity, moving the center of gravity fore or aft will alter the way the weight is distributed between the two, or even three points of the trailer (you have never seen a trailer fall back on its ar-e)?


I passed over this comment at the time, but on checking back, I believe Ian is right. Towball load does change with a WDH.

A Hayman Reese system is like two long levers attached to the back of the car. Lift the end of one and the car rear end rises.

Imagine the scenario of a mythical van in perfect balance (horrible for towing). A small child can manually lift the coupling off the towball. With the van connected, insert one of the Hayman Reese bars in the fitting at the back of the car and lift the end as much as you can. The back of the car and the coupling will visibly rise. Now attach the end of the bar to the HR bracket on the drawbar so it takes the weight. Do the same for the other side. The back of the car is now raised a bit and the front of the drawbar is being forced down onto the towball by the HR levers. Will the child now be able to lift the coupling off the towball? Absolutlely not.

So, technically, I believe HR is wrong saying towball weight does not change.

But it is irrelevant. It's only relevant to know the static weight when standing on the jockey wheel. In that contentious chart that caused so much angst, the weight on the towball is never zero. But it is irrelvant for the calculations, because once the car and van are coupled, that weight has become part of the weight of the connected rig and is no longer measured or known.

 



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You know I've come to the conclusion that this thread is not about WDH rather about how far some posters can pxss.
It is no longer informative!

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Are We Lost wrote:
iana wrote:

Well folks, to throw a spanner in the works, my thoughts are, is that a WDH does alter the downward force of the trailer coupling. It will depend entirely on how much the rear of the tow vehicle sags when the trailer is coupled, to when the WDH is adjusted so that the trailer is level.
Any rotation about the central axis will change the center of gravity, moving the center of gravity fore or aft will alter the way the weight is distributed between the two, or even three points of the trailer (you have never seen a trailer fall back on its ar-e)?


I passed over this comment at the time, but on checking back, I believe Ian is right. Towball load does change with a WDH.

A Hayman Reese system is like two long levers attached to the back of the car. Lift the end of one and the car rear end rises.

Imagine the scenario of a mythical van in perfect balance (horrible for towing). A small child can manually lift the coupling off the towball. With the van connected, insert one of the Hayman Reese bars in the fitting at the back of the car and lift the end as much as you can. The back of the car and the coupling will visibly rise. Now attach the end of the bar to the HR bracket on the drawbar so it takes the weight. Do the same for the other side. The back of the car is now raised a bit and the front of the drawbar is being forced down onto the towball by the HR levers. Will the child now be able to lift the coupling off the towball? Absolutlely not.

So, technically, I believe HR is wrong saying towball weight does not change.

But it is irrelevant. It's only relevant to know the static weight when standing on the jockey wheel. In that contentious chart that caused so much angst, the weight on the towball is never zero. But it is irrelvant for the calculations, because once the car and van are coupled, that weight has become part of the weight of the connected rig and is no longer measured or known. 


 Surely you jest? Perhaps you could visit HR,tell them the error of their ways,and set them on the right track? You could let them know that,for over 60 years,they've been doing things incorrectly? Over the last few years I have spent many hours,and provided much information and data to show how a WDH works,and this all is available on the forum if you use the "search" facility. "No longer measured or known" you say,to which I say "Rubbish".My own testing has shown EXACTLY how a WDH works,and ALWAYS the total weights on the axles with the WDH tensioned equals the total weights on the axles without the WDH tensioned.However,the total weight is distributed differently over the axles,as the WDH name would imply. Previously I have posted the figures from my testing,and I don't propose to do so again,as all that stuff can be found using "search.. For the 701st time I will say "a WDH does NOT change towball weight.Never has.Never will"  Cheers



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yobarr wrote:
.........
My own testing has shown EXACTLY how a WDH works,and ALWAYS the total weights on the axles with the WDH tensioned equals the total weights on the axles without the WDH tensioned.However,the total weight is distributed differently over the axles,as the WDH name would imply. .....

Agree 100%. I never said anything different. Once connected, the total weight of the rig on the wheels never changes regardless of whether the WDH is tensioned or not.

Consider my example above. You lift those tension bars and the back of the car lifts a little. Those tension bars feel mighty heavy. You attach them to the HR brackets on the drawbar. The drawbar is now taking that weight. Where does that weight on the drawbar go? Some goes to the caravan wheels. Where does the rest of it go?

Take it a step further ...

Once the WDH is tensioned, drive the rig over a culvert. It won't take much depth for the car back wheels to be spinning in air as the WDH does it's job. Those bars have now effectively lifted the back of the car entirely. They must be exerting so much downward force on the drawbar that it may buckle or crack under the weight, or one of the attaching chains or something else may well break. So, with all that downward load on the drawbar, where does that load go? Partly to the caravan wheels. But isn't most of it being taken by the towball? Surely that downward force from the bars is forcing the coupling harder down onto the towball. And that weight is then transmitted to the ground via the front wheels.

As before, the total combined weight on the wheels is unchanged, just redistributed.

 



-- Edited by Are We Lost on Sunday 19th of December 2021 11:44:09 PM

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Are We Lost, I agree with your prognosis, there is force expressed as lbs force, or KPA, when the WDH is tensioned, it is exerted down on the tow ball, and is an added force on top of the towball mass. I shudder to think what is happening to the structure of the tow vehicle and the trailer draw bar when traveling over undulations etc.

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iana wrote:

Are We Lost, I agree with your prognosis, there is force expressed as lbs force, or KPA, when the WDH is tensioned, it is exerted down on the tow ball, and is an added force on top of the towball mass. I shudder to think what is happening to the structure of the tow vehicle and the trailer draw bar when traveling over undulations etc.


 Hi Ian and Stephen. Thanks for these posts! Interestingly,I have just spent some time chuckling away to myself,as your theories mirror my own thoughts,ideas  and "logic" from some years ago,before I spent much time studying the subject,and learned "stuff". To save a lot of time messing around trying to help you, could I simply ask you to Google something like "John Cadogan WDH" where you will find a 27 minute video which clearly explains how a WDH works. In this video the way you two guys think is addressed,and clearly shown to be incorrect.Around 11-12 minute mark,and 18-19 minute mark are important parts of the video. As I said earlier,WAAY back,I thought almost exactly along the lines you do until I was enlightened.A WDH creates what is essentially a "stiff arm" from the car's front axle, through the hitchpoint to the van's axle group.Hope this video helps you,but if you still are unconvinced,could I suggest that you individually,or as a pair,approach both John Cadogan (Auto Expert Engineer of note) and Hayman Reese (WDH manufacturer of 60 years) to advise them of their ignorance! Good luck guys.Enjoy! Cheers

P.S The pictures show the video you should be looking for.

80E9DFE2-483D-4C17-A1EC-6775950086E9.png

 

AC141A9D-2A6B-4F70-ACB6-B4AE2071AB0D.png



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Ugh! 27 minutes of John Cadogan is a big ask. But I will get to it this afternoon.


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Hi All,
I will close this now. We are happy for members to disagree with one another; however we do not allow personal attacks. Please ensure that posts are focused on the topic rather than on the member who posted them.
Thanks.



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