This is part of a series of articles on building or rebuilding a caravan. You can find the whole series here: Ever Wanted To Build or Rebuild a Caravan?
The caravan chassis is perhaps the biggest hurdle home builders have to overcome. There are a few options on how you can tackle it.
If you are already a competent welder then you can probably do the whole thing yourself. We can tell you the basic principles and materials, but you need to closely look at the design of a commercial caravan that is built to the conditions and weight you expect to be. Axles and suspension can be purchased and attached.
If you are nervous about building your own chassis, we don't blame you, luckily there are other options.
There are professional chassis builders around, you will find them with a quick google search within your state or capital city. If you are unable to source something suitable you could measure up an existing similar quality chassis and provide the drawings to a welder to construct your chassis.
There are also some standard chassis available to purchase from some trailer manufacturers and even on eBay.
Another option is dismantling an existing caravan for the sole purpose of building on the existing chassis. This can give the option of changing the layout and perhaps reusing some components and materials.
The two main advantages of going this way is that:
(i) you are using a proven chassis and
(ii) as you dismantle the caravan, you can examine the way and the order it was put together.
This reverse engineering should not be underestimated, you should resist the urge to demolish the cabin to get to the fun part of building.
The disadvantage is that some of the very old caravans may have brake systems that are no longer legal, or the chassis strength may not suit the very popular 'outback' style, if that is your intention. If your intention is to get to the more remote areas, then a complete custom build maybe the answer.
While you do need to have a good strong suspension system, that doesn't mean it has to be the fanciest or most expensive.
Many modern Off Road Caravans have independent suspension but in my experience it can be more of a marketing feature than completely necessary.
I won't try and talk you out of one but if you have limited money you will be much better off going for a high quality standard Rocker Roller spring and solid axle than a cheap independent system.
One of my greatest worries is breaking a specialised suspension component in the middle of no where. Every bush mechanic can get leaf springs repaired.
But don't use slipper springs on a caravan, they are cheaper but best reserved for your 'On-road' camper trailers.
My latest personal van has Rocker Roller springs and solid axles, it recently did the Gibb River Road with no issues.
My current caravan is 20' long and a semi-offroad. The chassis was based on Roadstar Caravan.
A-Frame is 150mm x 50mm RHS, 3mm thick. It has a lower offset tension strap 30mm x 5mm.
The main longitudinal chassis rails are 100mm x 50mm RHS, 3mm thick.
The first half of chassis rail has an additional 100mm x 50mm RHS welded under the main chassis rail.
Behind the full suspension mounting, is a 3000mm long , 100mm x 6mm flat bar that is welded to the inside face of the main chassis rail.
The cross members, between the chassis rails are:
The outriggers protrude outwards from the main chassis rail to the wall supports:
These are as above
The floor side support is 25mm x 3mm angle
The Wall supports are short 50mm long, 25mm x 3mm angle.
Great place to shop they have everything at a great price and fast delivery this is the second time I've shopped with caravan plus wouldn't go anywhere else thanks caravan plus cheers Rob
Hey guys, the door was packed and delivered very professionally. The door itself is perfectly mate, Great service, I installed the door myself, which sits and swings perfectly. Thanks again
Excellent description on website of replacement parts needed, ensuring the correct fitting of the parts. Products arrived very quickly and new fan, screen and vent cover all now installed in van’s bathroom.
5 Comments
doug mackellar
hi could someone give some advice on where to buy a element for hws sw6dea as i cant get these working maybe there faulty ,many thanks doug.
Me
I contacted G&S and told we do not sell to single one off retailers or wholesalers. I was looking for a chassis to build a custom van.
Rene
is there any issue with building/welding your own independent trailing arm suspension?
Trevor
Can you clarify for me how the walls are supported on the chassis. I note your blog shows the following "The floor side support is 25mm x 3mm angle The Wall supports are short 50mm long, 25mm x 3mm angle." I understand the floor side support but am unsure what is meant by the wall supports. I assumed the wall would sit on the floor with the external sheet dropping down over the chassis. Can you advise or provide a diagram showing this please.
Nadim
I am completely new to camping and I want to travel around Australia doing various types of camping from your normal to off the grid camping. Also, I want to build my own caravan to my liking from the ground up due to my brake towing capacity is only 2000kg's. What I would really like to know is that: 1. What options and dimensions (including the thickness) do I have, to weld two identical trailers of up to 8 metres in length either using steel or aluminium? And, 2. How can one work out the overall weight difference between them? Thank you.