Uging 3x3 for s-10 Stock Floors?

Originally posted by pimptruckman92



a friend of mine and me were talkin about this about a year ago and he was plannin on doin a quad cab dually, and tossing around the idea of using2x3x1/4 or better on its side with 2-3 inserts of some super thick square tubing then welded the ends together and capped the ends.. and i was thinkin the same thing like why it wouldnt work if your adding internal walls to the rectangular tubing. and have properly placed crossmembers and maybe some extra round tubing to run along the driveshaft. ??? i understand the deflection. and i know that the longer the material the more leverage that can be exerted on it. but what if you were using rect. tubing on its side and all that i mentioned on a midsize or minitruck?

dude why even think about using 2x3 on a f/s? 2x4 fits super easy under the cab with no cutting......

and you might as well use 2x2 if you are gonna lay 2x3 on its side...

Originally posted by ///RA TROY



s10 forum sucks



that pretty much sums it up.

Originally posted by Russ-D



Originally posted by bdroppeddak



Originally posted by Russ-D



I am doing 2x3x3/16 on mine, but only under the cab, the back half will be 2x3x.083. Using 7 ga for plating.

I am doing the 2x3 with the 3 up though.

rusty i hope you are putting a 12 point cage on that frame, that 3x2 .083 will flex like a mother, i just built a frame from 3x2 .120 wall and used a bit of round tubing to triangulate the rear of the frame behind the cab and make sort of a "backbone" down the center to take alot of the flex out of it.......

it will have crossmembers on the backhalf, and the tubing is mandrel bent. I'm 1000 percent confident in my choice.



so what is this frame going under?

I think his Mazda?

I once heard that Steel isnt DOT Approved......just and fyi lol

Originally posted by notlowyet



so is there a difference in using a 2x3 with 2" high instead of 3" high?

i've always wondered this, but i can see how laying 2x3 sideways, would be like bending a ruler, when it's flat _ it's a whole lot easier to flex then when it's vertical |. kinda like that, but not really, haha.

Originally posted by DAWGPIMP



Originally posted by Russ-D



Originally posted by bdroppeddak



Originally posted by Russ-D



I am doing 2x3x3/16 on mine, but only under the cab, the back half will be 2x3x.083. Using 7 ga for plating.

I am doing the 2x3 with the 3 up though.

rusty i hope you are putting a 12 point cage on that frame, that 3x2 .083 will flex like a mother, i just built a frame from 3x2 .120 wall and used a bit of round tubing to triangulate the rear of the frame behind the cab and make sort of a "backbone" down the center to take alot of the flex out of it.......

it will have crossmembers on the backhalf, and the tubing is mandrel bent. I'm 1000 percent confident in my choice.



so what is this frame going under?





My s10.

argue with me dammit!!!

Originally posted by TukinRange



Thats the other thing about that deflection calculator, are they putting all the pressure right on the center of the beam with a hydraulic? Cause >correct me if i wrong? where the cab is connected to the frame or at the ends where it is gussetted? I think the deflection calculator was based on a single hydraulic pressing in the center of a beam, If im wrong please correct me like i said, But just wondering..

that is right as far as i know. when you hear about the test like that or see something on the tv they are alway testing it in the middle of the piece. with a frame the mounts are always on the ends of the tubing but the end cab and bed mounts not alway close to the end of the tubing but still very close. i'm not to sure that that chart is even worth looking at. there is really no weight put in the middle of the piece. very hard to say unless someone does that right for the right problem

y in the world would u want to lay the 2x3 on its side. Theress something called moment of interia - indication of the stiffness of the beam, which is the resistance to deflection of a beam while carrying loads that tend to cause bending. its the area between the top of tube and the center axis (basically the area of half the tube). Well to be efficent you want to place as much material as possible away from the the center axis, the more material the stiffer it will be. From the tables out of my machine design book, 2x3x1/4 normal direction has an value of I=2.21 in^4, while 2x3x1/4 on its side has a value of I=1.15 in^4. Basically grab a chunk of 2x4 and place each on on a jack stand, when its layed on its side it will bend with you standing on it, when its standing up the deflection so be unnoticable if any.

Edited: 2/7/2007 5:06:37 AM by lunatiksblazer

if u wanted to figure out the amount of deflection, like they did on s10forum, dont place the force at the middle, use a distributed force across the beam. theres a program that anyone can download a trial of called beam 2d and itll run all the deflection bullshit for u. Idealy if u wanted to find out your deflections of a chassis and u have the time, draw it in inventor or solidworks with both rails and all your cross members, and your can apply forces to different parts of the chassis.........god i sound like an engineer already and i havent graduated yet