The Engineering Design of Caravans

Possum3 · Guru

The Engineering Design of Caravans

Whenarewethere · Guru

Probably didn't let their tyres down!

Eaglemax · Guru

Possum3 wrote:
Just read an interesting article on Caravan Design.
If the basic design of a caravan is fundamentally flawed, one cannot have high expectations that the rest of the caravan will somehow be fine. https://www.facebook.com/CaravanCouncilOfAustralia/posts/2380272225412762?__tn__=K-R

Good post Possum

Before I embarked on my two caravan builds I read the Australian Standards for caravan building. And read it and read it. But of course if I had everything engineered I wouldnt have saved the $20,000 or so I was seeking to save. For example size of the RHS for the drawbar. Standards give you calculation for testing- "must exceed this or that". So, knowing my caravan was to end up with an ATM of 1000kg (towball weight max 85kg) I simply made note of the drawbar RHS sizes that caravans with an ATM of 1200-1500kg have. I ended up over engineering it with 65x35x3mm RHS far greater than some "C" channel used in some heavier vans. Over engineering also went into extra gusseting of the steel frame. Not much extra weight but much stronger.

Of course this is crucial to safety and insurance claims post an accident.

I often wonder how many manufacturers enlarge their plans, build a new design and keep the engineering of the chassis the same thereby saving engineering costs to do so.?

Tony

montie · Guru

Good advertising for CCA!

-- Edited by montie on Thursday 9th of January 2020 11:01:23 PM

Cupie · Guru

Whenarewethere wrote:
Probably didn't let their tyres down!

This demonstrates yet another advantage of a metal frame over a timber one. The timber would never have stood up to these typical Australian conditions. Aluminium even better than steel.

LOL

montie · Guru

Come on guys...be serious here!

We have caravan manufacturers sneaking around in the dead of night stealing each other's designs! blankstare

How low can you go! disbelief

Possum3 · Guru

montie wrote:
Good advertising for CCA!

The Caravan Council of Australia does NOT SELL anything. it is NOT a "Business".

It is run on an honorary basis - to freely assist 'vanners to avoid, and over-come the many serious problems with the industry.

The CCA is completely independent, non-commercial, non-profit, non-political... and does not have any "Members".

Colin Young is eminently qualified and experienced to provide professional and unbiased comments on all technical / safety / compliance caravan issues.

yobarr · Guru

Possum3 wrote:
montie wrote:
Good advertising for CCA!

The Caravan Council of Australia does NOT SELL anything. it is NOT a "Business".

It is run on an honorary basis - to freely assist 'vanners to avoid, and over-come the many serious problems with the industry.

The CCA is completely independent, non-commercial, non-profit, non-political... and does not have any "Members".

Colin Young is eminently qualified and experienced to provide professional and unbiased comments on all technical / safety / compliance caravan issues.

Possum,you need to be wary if using bold lettering for fear of being accused,by a few sensitive souls,of 'yelling'! Cheers

P.S I do understand that your highlighting is intended to draw attention to salient points,but some appear not to understand that.

montie · Guru

yobarr wrote:
Possum3 wrote:
montie wrote:
Good advertising for CCA!

The Caravan Council of Australia does NOT SELL anything. it is NOT a "Business".

It is run on an honorary basis - to freely assist 'vanners to avoid, and over-come the many serious problems with the industry.

The CCA is completely independent, non-commercial, non-profit, non-political... and does not have any "Members".

Colin Young is eminently qualified and experienced to provide professional and unbiased comments on all technical / safety / compliance caravan issues.

Possum,you need to be wary if using bold lettering for fear of being accused,by a few sensitive souls,of 'yelling'! Cheers
P.S I do understand that your highlighting is intended to draw attention to salient points,but some appear not to understand that.

Take more than a few bold letter words to affect my sensitivity! smile

Other than making generalised and unsubstantiated statements about the apparent shortcomings of the Industry what exactly does the CCA contribute?

Possum3 · Guru

Montie Wrote,
Take more than a few bold letter words to affect my sensitivity!
Other than making generalised and unsubstantiated statements about the apparent shortcomings of the Industry what exactly does the CCA contribute?

I have no affiliation with CCA or Colin Young other than personally using his services as an Automotive Engineer and I am certain that many shortcomings of Industry can be substantiated, although none are listed on CCA site.

None the less, Colin Young provides concise and accurate technical data on all aspects of the Caravan and Motorhome industry. It has checklists that can be downloaded (Free) for many subjects, technical, buying loading, towing, maintenance, etc.

In fact, Colin Young has written RV Books enhancing the Image of the Australian RV Industry. Assisting RV Manufacturers & Importers, Dealers, Owners & Potential Buyers.

What does Montie contribute???????

Greg 1 · Guru

The comment about metal frames being better, there are fors and against both materials with timber having some real advantages over metal in a couple of areas. It depends on what particular strengths that you want. I have owned both types of construction at one time or another, and have not found either to be better than the other in a total sense. I look for a robustly built van more than worry too much about the materials the frame is made from. My current van is timber framed traveled about 60,000ks and has stood up very well over some quite rough road with no signs of movement at all. My previous aluminium framed van the same, but both were well built which is the secret.

montie · Guru

Possum3 wrote:
Montie Wrote,
Take more than a few bold letter words to affect my sensitivity!
Other than making generalised and unsubstantiated statements about the apparent shortcomings of the Industry what exactly does the CCA contribute?
I have no affiliation with CCA or Colin Young other than personally using his services as an Automotive Engineer and I am certain that many shortcomings of Industry can be substantiated, although none are listed on CCA site.
None the less, Colin Young provides concise and accurate technical data on all aspects of the Caravan and Motorhome industry. It has checklists that can be downloaded (Free) for many subjects, technical, buying loading, towing, maintenance, etc.
In fact, Colin Young has written RV Books enhancing the Image of the Australian RV Industry. Assisting RV Manufacturers & Importers, Dealers, Owners & Potential Buyers.

What does Montie contribute???????

35 years as a dealer providing good honest service and active member of Industry associations should answer that.

Regarding the engineering criteria that goes into building a van, well the answer to that can easily be found by contacting people like Alko for chassis, Cruisemaster for suspension, Dunlop for tyres, etc, etc. A chat with a van manufacturer will reveal the geometry used to set ball ratings etc.

Once that research has been done it can then be posted to support any engineering shortcomings instead of simply making generalised and unsupported claims and then ducking for cover. So far I have not seen one link or report that verify any claims made by the CCA. Maybe we have to buy one of the RV books! blankstare

On a few occasions in the past I have asked for supporting links from the CCA to verify some of their claims but no response.

As for caravan manufacturers sneaking around copying each other's "designs", well that's just a load of cobblers. Most manufacturers purchase their components from the same suppliers for chassis, suspension, ancillary equipment and of course appliances. You could hardly call that "copying". Again if the CCA has some supporting evidence that this is happening now would be a good time to produce it!

Stretch60 · Senior Member

Whenarewethere wrote:
Probably didn't let their tyres down!

Great Central Road?

Whenarewethere · Guru

Yes.

Saw a fair number of people towing. Going way too fast for the road, saw one caravan probably doing 130kph. We dropped tyres to 24 psi from Laverton to Kata Tjuta. At the start we purposely did 5 km at normal pressure to get a benchmark. It makes a massive difference for comfort reducing type pressure & we only did 80kph max.

Let your tyres down for these roads & get a high speed pump so it is quick to pump 8 tyres back up!

A bit of road in NT over the border from WA:

https://vimeo.com/364281135

miroku12g · Senior Member

Sorry for posting this here, need some advice ?
I have been receiving daily emails for a few years now on the general forums,eg; pick this place etc, the last email i had was around 2 weeks ago and haven't received any since then, has anyone any ideas why I haven't had any ? I'm not aware that i have pushed UN-Subscribe by mistake.
Seems strange as to why & don't have an answer how to start receiving mail again
Apologies for posting here

Regards
Dave & Maz

Iva Biggen · Senior Member

Thank you for the link Possum3,

I would not take too much of anything our resident caravan salesman or his string puppet say on here.
This is just another example of a person with no qualifications in engineering informing all on here that they somehow have gained cornflake packet recognition.

The full moon has once again got the werewolves howling for blood.

The article brings up some good points.

Cheers

Ivan

Whenarewethere · Guru

It is easy to accidentally subscribe with the proximity of the buttons on the website layout.

First log in. Then the easiest is go to one of the emails you get & click unsubscribe.

PeterD · Guru

miroku12g wrote:
Sorry for posting this here, need some advice ?
I have been receiving daily emails for a few years now on the general forums,eg; pick this place etc, the last email i had was around 2 weeks ago and haven't received any since then, has anyone any ideas why I haven't had any ? I'm not aware that i have pushed UN-Subscribe by mistake.
Seems strange as to why & don't have an answer how to start receiving mail again
Apologies for posting here

Go to the top RHS of this page and under "Logged in as" click on your forum name. On the LHS you will see a list of links you can see what is going on and fiddle your settings. Click on "Subscriptions" and you can see what you have subscribed to.

To subscribe to the particular forums you wish to receive notices of new posts, go to the of that forum and you will find a link "Subscribe" in the bottom RH corner, click on that to subscribe to that forum.