homemade rocketbox - car top carrier

[RuMR]

reaction at the roof connection is the same whether you spread the load or not...i think that is probably the weak spot...not the actual rack beams...

 

deflection of the crossbeam doesn't necessarily mean that's the load limit state...

[tradhead]

Rumr - Agreed that ductile is good. A low strength, brittle bolt would be worse. My thought with mentioning ductility is that for me it is frustrating when you try to torque a 300 series stainless bolt and it just stretches instead of pulling up tight under the desired preload.

 

Also to the point on the size of the bolt, it's true that anything over 1/4" in chrome-moly is overkill. I was trying to provide a comparison of relative tensile strengths for 300 series stainless vs. chrome-moly steel bolts and didn't really consider the specific loads involved for the roof rack application. Sorry for sending the wrong message.

[rbw1966]

I have a rocketbox that I bought off someone here and I love it. Its reasonably aerodynamic, holds a LOT of gear and best of all, keeps that gear out of site. Some may argue that its not terribly secure but in the ten or so years that I have had this box its never been broken into, never damaged and still works just as well as the day I got it. I almost never keep my gear in my car, its always in the box.

 

I will say that if its completely empty it rattles like a sonofabitch so I always keep something in it.

[mark1980]

I think Yakima will be calling you soon, offering you a consulting position in their R&D department. The thing is stout to say the least. The 150 lb limit is for while you are driving at 70 mph. While it's parked, I think you could hold a dance contest on top of it, or pitch a tent. Some sort of quick release attachment would be an improvement, as would be the table legs. Maybe the legs could be incorporated into a perimeter railing. Then all you will need, is three more yellow boxes, which could be used as chairs, for a table for four. We will do the boxes foam core this time, vacuumn bag them, lighten them up.

[merganzer]

 

Made this box in 2004 in northern Minnesota Drove it west to Seattle with a side trip south to jtree in January/February as a moving road trip. It was packed to the max although I do not know the exact weight. I still use it as a storage box.

 

I just went to the hardware store bought some 2x2's for the frame, a sheet of marine grade plywood, a can of primer, and some caulk to fill gaps. Just went to work after some simple drawings and a little thought.

 

You should give it a go and see what you get.

[markwebster]

nice looking rocket box! My wife wouldn't let me build my own box, said it would look to trashy, she's seen my carpentry skills. But I love my body bag. We've been filling it full of skis and poles lately. A couple bungies to tie it to the board and its ready to roll. I can't remember if I mentioned that we used the bodybag as a spare refrigerator under a boulder in jtree at xmas. The fabric is dog proof.