dyce51
Well-known member
I am wanting to go to buy the steel for my truck arm suspension. I am going to use 2" X 3" tubing. What wall thickness is suggested...1/8" or 1/4" ??
a lil advice needed....
- Thread starter dyce51
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Bonehead
Skull Master
Not 1/8th so 3/16 or 1/4, what is the set up, how much weight and pressure?
dyce51
Well-known member
I'm building a 1951 Ford F-1...Wanting a truck arm suspension in the rear with air bags. very simple but effective suspension....not sure of the weight...
donsrods
Well-known member
I agree with Gastrick, I'd use 3/16.
Don
Don
Bonehead
Skull Master
I agree with Gastrick too. 1/4 would not hurt anything though.
Bonehead
Skull Master
I agree with Don.
dyce51
Well-known member
so 3/16" will be strong enough while still having a lil flex to it?
Unkl Ian
Allergic to Idiots
How long are the arms going to be ?
truck arms
I used to work in a shop that ran in the Craftsman truck series, one of the jobs I had was to build truck arms occasionally. The ones we used were 3/16"
but they were not tubing. They look like I beam, but actually there channel welded back to back. 1/4" wouldnt hurt anything, might just be a little extra weight. I have a lot of things on my truck that 3/16 would have been sufficient, but I had a bunch of 1/4 lying around so thats what I used.
I used to work in a shop that ran in the Craftsman truck series, one of the jobs I had was to build truck arms occasionally. The ones we used were 3/16"
but they were not tubing. They look like I beam, but actually there channel welded back to back. 1/4" wouldnt hurt anything, might just be a little extra weight. I have a lot of things on my truck that 3/16 would have been sufficient, but I had a bunch of 1/4 lying around so thats what I used.
donsrods
Well-known member
We hot rodders tend to overbuild everything, which is very good. Better to err on the side of safety rather than have something break. If you look at some of the stuff the factories do you will see some very thin brackets and welds that are not much more than spot welds, and these were designed that way by automotive engineers who evidently know stresses and all that stuff.
When we were building that front motor mount crossmember for Dans car we used 3/16, and when it came time to do the little 3 inch motor mounts that sit on top to bolt to the stock motor mounts we dug out a set of Pete and Jakes radius rod mounts that were not being used. They were the perfect shape, all we had to do was cut them shorter. What concerned us though was that they are stamped from 1/8 inch steel.
After some back and forth discussion we decided to use them because if they were made to support the stresses of a radius rod tugging on them, they must be strong enough to act as a simple motor mount. We did use them, but Dan didn't feel comfortable with that, so he put a 3/16 plate inside and welded that in, then he added a fourth wall to them out of more 3/16 plate.
So I guess steel is stronger than we home builders realize, but we just sleep better at night if we use thicker stuff and weld the heck out of it.
Don
When we were building that front motor mount crossmember for Dans car we used 3/16, and when it came time to do the little 3 inch motor mounts that sit on top to bolt to the stock motor mounts we dug out a set of Pete and Jakes radius rod mounts that were not being used. They were the perfect shape, all we had to do was cut them shorter. What concerned us though was that they are stamped from 1/8 inch steel.
After some back and forth discussion we decided to use them because if they were made to support the stresses of a radius rod tugging on them, they must be strong enough to act as a simple motor mount. We did use them, but Dan didn't feel comfortable with that, so he put a 3/16 plate inside and welded that in, then he added a fourth wall to them out of more 3/16 plate.
So I guess steel is stronger than we home builders realize, but we just sleep better at night if we use thicker stuff and weld the heck out of it.
Don
Willowbilly3
A *real* tin magnet
I think the design is more important than the thickness. I too have seen some very light weight but strong stuff and some very heavy but weak stuff. I would go with .120 wall and reinforce key areas.
I built my rear frame section with .090 wall but it will have lots of other things going on.
I built my rear frame section with .090 wall but it will have lots of other things going on.
dyce51
Well-known member
the arms are going to be 56" long...they will have the air bags mounted about 1' forward of the rear axle to them. The front will be either rubber or urathane bushed and mount solid to the rear axle. The will also be angle in toward the tailshaft of the trans.
