Advice and opinions ......

[Buddha Boy]

Hi All - I have my rough sketch completed for my truck camper. I plan on having a 7' long by 3' tall extension over my cab as a sleeping area. That will keep the 7' bed of my truck free for kitchen, heater, refrigerator, batteries ...etc...

I am going to fabricate a shell that will sit on the rim of my bed ,no slip in, and just insulate the walls of the bed and floor.

I need to park in tight spaces at work and keep my rig "stealthy" so the sides of the camper will not stick out much further than the side of the truck.

The "nose" of the cab over: should it be curved or sharp angle to top for wind resistance?

How many inches clearance between roof of cab and bottom of cab over? (I am not sure how much deflection I will have if I go down down a steep bank and up the other side.)

I saw a picture of a camper made out of 1/2" ply and painted. I believe that I will only need the shell for two or three years and then I will have completed my bus conversion. I can sell or just trash my camper after that.

Or: 1/8" plywood on camper frame spread fiberglass over that and paint.

I would appreciate any suggestion and advice. Thanks! ~BB

[Mark R. Obtinario]

The biggest problem with cabover sections is most are not built with enough to hold the cabover section up.

Think in terms of a cantilever deck. For every foot of unsupported cantilever you will need a minimum of one foot back into the camper body to support the cantilever.

The point at which the cantilever begins will become the fulcrum upon which the lever will be balanced. A fat boy like me asleep at the front of the cabover is going to put a lot of down pressure that will be lifting the rear of the camper up.

A lot of the problem can be eliminated if you use some sort of strut in front of the windshiled to support the cabover. If you use some sort of support strut then you can utilize lighter materials to build your cabover.

Good luck.

Mark O.
Winlock, WA

[Rudy]

Mark makes a good point. In building cantilever decks on houses, I've always used the 1/3 out and 2/3 in support formula.
Take a look some photos of housetrucks. You will often see support posts coming up from the front bumper. That is a good way to support the cabover sleeping area.
There are also other methods such as depending upon the shear value of plywood on the sides of the camper. That is how Class C campers and slide-in pickup campers support their cabovers. Ultimately, though, those systems end up failing. I like the support post system.
If you don't want to use that system. you should incorporate horizontal bracing built into the inside of your housetruck walls. 1/3 out and 2/3 in is the recommended formula for cantilevers.

[Buddha Boy]

Thanks for the data Mark. What do you think about this: Angle iron X brace on each side of cabover welded to top support of rear box with cabover bottom rear resting on/welded to angle iron support in main box? If that would work then I just need to get the best size of angle iron to reduce weight yet provide support.

Lol, yeah I'm 235 right now and my girl is making me go on a diet so weight in the cabover and at my belt is of primary concern! I just have to figure out how to get a little lovin going with only a 3' ceiling!

Mark, I appreciate you taking the time to give me feed back! Thanks. ~BB

[Rudy]

BB, Metal is strong. I have done two retrofits on the outside of Class C campers to support the cabover. They were L shaped and bolted to the sides of the camper and the bottom of the cabover.. Ugly at best, but worked. If you can employ metal in the building of your house truck, you could hide it and still have good support.
If you have the horizontal space within your walls, consider the cantilever approach. That can be done with wood. Use 2X8 cantilever joists.
Just some ideas. Keep inquiring, and you will find out what works for you. Rudy