structural wood for a truck box body

[Redd]

Hi all.

So I'm building a camper box for my 4x4 truck. I bought an ex-asda fridge box. Its too big, so I'm going to cut it apart and use the panels to make a smaller box.

This box is joined at the edges using extruded aluminium. This is fine for a fridge unit but I'm making a camper and I want the camper to be warm. The aluminium protrudes into the inside of the box and therefore will be a cold bridge, transmitting cold into the interior.

So what I want to do, is use wood to join the panels. I created the below diagrams to show what im thinking.

What I would love to ask you guys is, what kind of wood would be suitable for this?

It needs to be strong.
It will likely be exposed to water.
It needs to be available in 80x80mm and in 11 foot lengths (the length of my box)

Advice on treating the wood also appreciated. I haven't undertaken anything like this before. Its my first time working with GRP panels, and sikaflex.

In fact any and all insight or advice appreciated and soaked up, I havnt a notion what im doing lol

truck

regards

 

[NazNomad]

First choice would be Ash, but where you'd get it I have no idea.

 

[Beau]

Yes I would second ash. The traditional wood used for coach work I believe.

Do you need 80mm x 80mm? Just join up a piece of 80x40 and a 40x40. Getting well dried wood that will finish at 80 mm thick is not easy but easy to get 50mm thick which would finish at 40mm is not a problem.

 

[Woodmonkey]

Much easier just to use the angle aluminium and then just insulate it surely? Wood would be my last choice of material for that

 

[Redd]

Cheers Naz, Beau.

Gonna level with you guys I dont know a lot about wood, I've made some things but I'm a total novice really, I make things constantly but usually in steel. Going to go have a look at where I can get ash now, that's excellent.

I can join two pieces no problem, can I ask please why dryness is a consideration?

Should I treat the wood beforehand?


_____________________

Woodmonkey hey there, just reading your post now. The problem is that there isnt a lot of surface area for the sikaflex to grab onto, so the idea behind the wood is to give the adhesive more surface area to hold onto. Here is a drawing I did yesterday that illustrates what im saying

Below is an image of a panel that has been manufactured specifically for a camper truck build. This is a foam panel like mine, but with a perimeter of wood to help bond the panels. There is a groove cut into the wood so that the sikaflex has more traction on the wood.

Here is an image of my panels. I'm going to use the router to remove the foam to a uniform level and then insert the wood corners.

I welcome criticism, this may be a rubbish idea! I've run it past a few people and it got okay'd, so i said id bring it on here and see how it went.
The wood will be helped by the right angle aluminium, if strength is your concern.
Wood also will not be a cold bridge.

I'm trying to get as much info and opinion as I can, before taking a consaw to the box.

Edit: reread your post again, I missed a point you made about re-using the aluminium, and insulate it. I did think about that, and thinking about it further it seems valid, but an issue I have is that I doubt I'll be able to rescue the alumium, sikaflex and similar materials are not designed to ever come apart.
I was considering burning it off.. be a mess though.

 

[SteveF]

how about just put a 50mm square stock inside and screw angle from outside to the wood inside
no need to hollow out insulation
just butt joint and screw through

Steve

 

[nev]

Why not just use a larger aluminium angle fixed on the outside of the box and butt the panels together inside?

 

[Redd]

like this?

That would be a whole lot simpler, I like that!

 

[SteveF]

like this?

That would be a whole lot simpler, I like that!

Yes, only concern now I mentioned would be how strong are the panels?
you may need a 41mm nylon\steel tube so you don't crush them

Steve

 

[Adam9453]

I think Nev was suggesting you don't need the wood inside, just bolt through from the outside, use washers and nuts on the inside of the panels.
If you are used to working with metal then building the large angle frame and just cutting the panels to fit inside should be much more straightforward.
I'd put the ceiling in first and then put the walls underneath it so the ceiling is held up both both the bolts and the vertical walls below it.
Looks like a fun project in a giant meccano kind of way

 

[Redd]

hmmmm.

food for thought alright. Yes I like the adult meccano aspect of it

There is a German forum called womobox.de and so far as i can tell the entire forum is about building these things, offroad living cells.
I had a plan to go on there and say, Hi, I dont speak German, how do you bond these things, can you reply to me with pictures please?

had a plan...

...For now, its friday, and I'm going drinking. Cheers for the replies guys, seems a lot more possible now. I'll return to this next week.

 

[nev]

Anything going on the walls inside, like cabinets? If there is you'll need to line it with ply or similar I imagine, in which case batons in the corners and at intervals along the sides ( effectively a stud wall) will a) give you something to mount it to and b) give you a gap in which to insert more insulation, run cables etc, thereby probably negating the cold bridge problem?
maybe?

 

[deema]

I would have thought that Douglas fir would have met your requirements. You can get the size your after, good resistance to rot, tales paint extremely well, and a semi harwood in terms of strength.

 

[skipdiver]

I'm confused by the suggestion of ash as i thought it was classed as non durable. I know it's used in Morgan car bodies which is also confusing to me as i've read that it's not really suited to outdoor structures. I know it is strong and light, so does it need to be suitably covered against water to be used for such applications?

 

[No skills]

Hmm, continue with foam removal in edge of panels - insert square section timber into recess with sika or a foaming pu glue and add the odd screw through panel skin into timber also.
Butt joint panels together at 90 degrees and screw through them so your screwing the wood together.
Remove any paint on edges of panels where ally angles are going, add liberal amounts of sika and cover with ally angles and also screw through angles into panels.
Belt and braces.

Jmo