Box section wall construction

[Billy Onions]

Hi everyone,
great forum. I have been lurking around here for a while, and this place gives you so much to think about.

My plan was to build a skeleton frame from 3/4" x 3/4" square hollow section. I was going to insulate the walls and roof thten skin with aluminium outside and a thin ply on the interior.

The frame would be galvanized and bolt to the chassis, which is to be constructed from 1.1/2" x 1.1/2" SHS and also galvanized. The frame work for the cabin area will be included in the skeleton, fully welded to support plyboard cabinets and shelving.

Can anyone see any problems with this or has anyone done anything similar?

I should point out that my tear is being built with the British summertime in mind.

[Bristol Delica]

Hi Billy

I'm building mine using 12mm ply for the external skin, 34mmx34mm softwood for the internal and roof struts and lining the inside with a combination of T&G and 3mm ply using 25mm polystyrene for insulation. Although the 12mm ply is pretty structurally sound on its own I felt that creating box section would add strength and rigidity as well as allowing for the necessary insulation needed to make it usable during colder weather.

The galley hatch and side door are made as separate box section units.









HTH & best of luck

IanJ

[Billy Onions]

Hi Delica,
that is a tidy job you have done there. If my woodworking skills were that good I would probaly go down that route if I'm honest. Unfortunately they're not, so until someone comes up with a flux coated twig and a method of welding wood I am lumbered (pun not intended.)

The main reason I asked is I am worried about about condensation. But as I am a self employed fabricator with a section bender, pipe bender and a lot 20mm box section lying left over from a job I did recently then I thought I should really be looking to exploit it.

Hope you are going to keep us informed of your project it looks a good solid build. I don't suppose you know of any gatherings for Teardroppers in the UK do you? What undergear are you using

[Bristol Delica]

Hi

Bit of a misunderstanding there......... I was think box section as in composite hollow panel, not box section steel! Woodworkers brain!

There are a few of us building in the UK, I was drawn into the whole thing by a friend in the owners club for my 4X4, a Mitsubishi Delica, he had stumbled across Teardrops and showed me what he was up to, I was immediately bitten by the bug! If you look at the top of the this forum you will see a link to TearJerkers which has a section for European builders, there are 3 or 4 Brits active there. Deli Dave, the guy who got me started, is the closest to having a usable trailer at the moment so any gathterings would be a little solitary! When we all get on the road I am sure a meet will be arranged.

My welding skills are as lacking as you say your carpentry ones are. It is skill I keep promising myself I must learn.

The only possible draw back of using box section steel I can see is weight, but as it is so strong I wouldn't think you would need to use too much to get a stable frame and then you can choose you covering. Marine ply seems to be the favourite as it is easy to source and reletively cheap.

As to condensation I am fitting a couple of through the floor vents and see if that is enough, if not I am considering fitting a couple of PC cooling fans in the walls as they run off 12 volts and are very quiet but still move quite a lot of air.

As a starting point I used 1980's 2 berth Trophy caravan I bougth off ebay for 50 quid and removed the body and cut the floor panel down to size and shortened the chassis. Dave used an Alko chassis from a caravan and cut it down and made a wooden base to build up from, I am sure you could achieve a similar thing with your materials and abilities. However you could make a chassis from scratch and buy some stub axles and tow hitch.

Cheers

IanJ

[Billy Onions]

Cheers Ian,
just registered with tearjerkers.
WHo's have thought the language difficulties would be with another brit on here.

[Bristol Delica]

Cool Lee

See you there.

IanJ

[mechmagcn]

Do you mean a frame sort of like this?

This is what I hope to be a teardrop someday

[Billy Onions]

That's exactly the kind of thing I was thinking of. I was hoping not to have as much bracing. But that does look a bit bigger than an 8 x 4 is it?

How did you find bending the teardrop profile? Did you follow a template?

[mechmagcn]

The actual TD body will be 5' by almost 11' by the time I am through with it. Bending the tubing was one of my biggest hold-ups to getting started, I couldn't find anyone local that could roll square tubing, so I ended up doing it myself. The front profile was rolled around a 48" tractor turf tire and the rear was rolled around a 34" truck tire. Only problem I had was keeping the tubing from twisting as it bent, this was accomplished by holding it straight with a wrench.
I'm hoping to start sandblasting the frame and at least get it painted this weekend.
Surprisingly, the frame isn't very heavy. I can easily lift the rear of it with the front sitting on a stand.

[ARKPAT]

Very good job Jeff.
Looks like you will have plenty of room inside.


Pat