trailer box frame

[kjg26]

I'm building off a m416 trailer frame. I plan to have box that is around 20-24" tall. Plan is to have 4 corner posts as well as 2 on either side, 2 on the front with some cross bracing.

I was given some 1x1x.120 square tubing i'm hoping to use. Is this going to be substantial enough? Or should i suck it up and purchase a stick or two of something heavier/larger?

Eventually it will have a lid and a RTT.

 

[croix]

I think that with a mechanical engineering degree and a good CAD program I could create a design out of 1" steel that would work. Since I don't have either of those, I would probably be more comfortable with something a little bigger; especially at the corners. 1"sq.x.120 tube is actually pretty strong. I've seen deflection calculators and yield strength tables which all make it look like 1" square tube should work, and I'm sure that in static conditions it will. Things get a LOT trickier when you add things like inertia, momentum, point of deflection, etc.
.
It really comes down to your intended purpose and how comfortable you are with your design (bracing etc.). It's a balancing act between cost, weight, and strength, but I would personally rather overbuild and feel comfortable on the trail rather than push the limits and be scared of a failure the whole time I'm out there. I should warn you that I'm just a computer geek and my two cents on this is probably worth about 1/2 a cent. Good luck.
-croix

 

[RagnarD]

Do you plan to put any weight on top? If not, I would go for lighter material.

I used 1" .120 wall square tubing as cross members on my roof. The span is about 6' and even with expanded metal welded to it, it noticeably sags when standing on it.

My next box/roof will be made of 2" 14ga (.075").

1" .120 is 1.44 lbs/ft

1.5" .120 is 1.84
1.5 .075 (14ga) is 1.32

2" .075 is 2.16

 

[tomr67]

I used 14 gauge 1 1/4"

http://www.expeditionportal.com/forum/threads/142388-hf-camping-gear-trailer-build

 

[TheFutur]

I used 1x1x0.1 inch square tubing for mine and it worked perfectly. Mu brother has a BA in mechanical engineering and a masters in naval architecture so he was able to calculate all the stress points and what not..