Maranti Timber Frame vs Sandwich Composite Construction

rexboggs5 · Senior Member

Maranti Timber Frame vs Sandwich Composite Construction

Plendo · Guru

We have a meranti framed van, along with most of the rest of people with Australian vans. We have just returned from the UK, where their vans are much lighter than ours, and mainly sandwich panel construction.

After seeing the lightweight vans in the UK I was asking a van mechanic I know, and cautioned against the light weight sandwich panel vans, firstly because they do not stand up to well to our rougher roads. The second reason surprised me. Sandwich panels have styrene cores, and many ofthe common cleaners here in Australia attack the styrene, thus a minor leak can result in hollow walls!

I have no doubt sandwich panel is the future, but I do not think we are there yet.

Desert Dweller · Guru

Yes if there's a leak in the outside metal skin the timber frame rots out. Seen lots of images on the net showing the extensive damage caused. We went for ''sandwich panel'' over ''tin & sticks''.

Grumpytoo · Senior Member

You can also have aluminium frames - strong, lightweight and rust proof

rexboggs5 · Senior Member

Hi Grumpytoo. Do you know of some brands and/or models of caravans that have aluminum frames?

baysidetas · Veteran Member

Re aluminium frames

In the event of a collision with a tress or an awning for example, a wooden frame will suffer damage in a locallised position whereas an aluminium frame will suffer damage over a much larger area as the aluminium frames bend rather than fracture. I have personally seen this on several motor homes and there is no reason why it would be different on a caravan.

Barrie

Peter_n_Margaret · Guru

I built the OKA camper body 11 years ago from fibreglass sandwich panel from here vanglass.homestead.com/

It is held together with Sikaflex.
It has now done 170,000km of serious bush travel.
It is as good as the day it was built. Incredibly tough stuff.

Cheers,
Peter

jade46 · Senior Member

Foam sandwich has worked for years in yacht construction without any major problems from water or rough treatment.A much harsher environment then most caravans will ever see in my humble opinion

-- Edited by jade46 on Monday 31st of August 2015 06:56:16 AM

banjo · Senior Member

We have had two timber framed vans (the worst due to constant leaks and rot never ever again) one aluminium framed van, still leaked like a sieve but no frame rot, just stained lining that looked bloody awful !

Had two composite vans now, a Trailstar and now our 5'er, never ever go back to dinosaur build methods, no comparison at all, lighter stronger totally waterproof skin, warmer/cooler due to superb insulation qualities.

It's the future, and any so called mechanic saying they are not built for aussie roads hasn't got a clue, has probably never owned one, but just listens to the usual crap around the bloc.

No timber = no rot, simple, and as for being difficult too repair, more bull dust, far simpler and cheaper to repair than any stick and tin monolith. Have a look on CForum in the horror stories thread, not many if any composite vans there.

Just be aware not all composite vans are created equal, some still have hidden plywood floors and sub standard fibreglass skins, our 5'er has no timber anywhere in the body or floor to rot or get wet if a leak was ever to develop down the track, it's called peace of mind.

Grumpytoo · Senior Member

Ours is a Coromal but is 8 years old. Not sure if they still build them in Aluminium.

Baz421 · Guru

Some good comments here. I'll add some brief comments only as I'm don't have fixed views one way or the other.

1. Visit the factory to see your van built. We visited 3 and all had major issues as far as we were concerned, welding chassis, rough work hidden where possible and wiring that looked like a rats nest etc.

2 One well known aluminium frame brand had tiny pop rivets inside holding the frame together and used the outer and inner lining for strength,,, many often think they have a fully welded frame, but is it????

3. Saw a timber frame van when we were watching ours being built that had jack knifed into the LH side of a cruiser,, major damage to cruisers rear quarter panel, back area and door and roof,,, very minor localised damage to van easily repairable (owner wanted it written off but easily repaired). I was amazed when I stood next to the van and saw the minimal localised damage.

4 Let a contract for sandwich construction 4wd truck with body like a van used in the bush, it had some issues with weight, flexing over rough creek crossings, and sealing panels at the joints al be it not like a standard aluminium skin. If the chassis flexes more than the body you could have major issues. Someone posted pics of the truck in the bush a couple of years ago so it's survived about 8 years so far.

So in summary, each construction method has it's pros and cons,,,, but the message I'm trying to convey is don't take things for granted,,,, ie one method is better OR worse for one or two reasons only AND LOOK FOR YOURSELF - VISIT THE FACTORY AND SEE FOR YOURSELF. Take someone with some knowledge with you if necessary.

For ANY type of construction it's the BUILDING QUALITY THAT DETERMINES IT'S LIFE SPAN

Just my 2 cents worth again.

-- Edited by Baz421 on Tuesday 1st of September 2015 12:01:52 PM

rexboggs5 · Senior Member

Thanks very much, folks, for these very useful and considered replies.

rexboggs5 · Senior Member

banjo wrote:
Had two composite vans now, a Trailstar and now our 5'er ...

Banjo, which brand of 5th wheeler do you own?

Graden · Veteran Member

Hi, Bailey c/vans are a composite and very strong. We looked at them before choosing a Swift, better value and stronger construction methods, same as used in modern fighter plane construction. Try this link to the latest Bailey test in the outback.
http://www.caravancampingsales.com.au/content/news/2015/bailey-vans-conquer-corrugations-53502?utm_medium=email&415+CID_9e27125d0b1f1902495a3208f8cd8f0d&utm_source=newsletter&utm_term=Read%20more

The Phantom · Guru

Plendo wrote:

After seeing the lightweight vans in the UK I was asking a van mechanic I know, and cautioned against the light weight sandwich panel vans, firstly because they do not stand up to well to our rougher roads.

Any evidence that Australian roads are rougher than European roads or is that just another all encompassing statement made in an attempt to convey superior knowledge.

The Phantom