Retro caravan project homebuild

[Robbieretro]

Good afternoon all.

I have been working on a plan to build my own retro style caravan from scratch for the past couple of months. It will resemble something along the Airstream look.

I am wanting to start with a real sound base and chassis, a flatbed approximately 4200mm x 2000mm.

I personally won't be welding this because of my lack of experience and confidence however I will be designing the specification and materials for my welder!

Having searched high and low for any definitive specifications / guidelines for chassis construction my search has been inconclusive. I am hoping maybe someone on here has experience in this field!!

I have attached three basic drawings with dimensions in the hope it explains what I am trying to achieve.

The main queries I hope someone can help me with are:

- Positioning of the centre line / axle of the wheels (indespension single 1500KG)
- Box section thickness of chassis frame. This is currently drawn as 100mm x 50mm for the external frame and 50mm x 50mm for the cross members. Tow bar 100mm x 50mm welded under main bed.
- Length of tow bar from front of bed to middle of tow ball

If there is anything else I haven't considered at this stage please feel free to point it out as I really am a complete rookie in this field!!!

I am aware this will need registering and also I want something to last so will be happy to conform to all procedures.

Many thanks in advance for your help.

 

[southpier]

the body work should be interesting to watch. quite an ambitious undertaking for a "rookie".

 

[Ozarker]

Is there a reason for the mitered corners in the frame? Twice as much welding and prep, harder to align and fit, if you're paying the welder they will be charging for that I'd think. Rounded or angled gussets on top of a square corner can be welded on pretty quick and used to form the body. Good luck

 

[Robbieretro]

Thanks. I wanted to achieve rounded corners to the body so thought this would give me the coutours I needed?

This picture is what I'm wanting to base it on...

 

[Robbieretro]

the body work should be interesting to watch. quite an am

bitious undertaking for a "rookie".

Haha yes indeed...!

 

[ottsville]

Welcome and this looks like a cool project!

Are you building a trailer for off road use? Most of the advice you will get here will be biased in that direction resulting in a heavier than necessary frame if you are going with on-road use only. I would suggest looking at the frames under some campers to see how they are actually built and the thickness of the material. Most commercially made camper trailers are using some type of c-channel, usually around 1/8" thick.

There's more trailer info over on TNTTT.com and I know I've seen some DIY RV pages.