what is the best material for control arms?

i plan on building ladder bars but i guess u can just relate them to control arms. i plan on using QA1 rod ends on the frame end- i was looking at using the PCMR10-12 or the XMR10-12 which both have 3/4" threaded ends. wi them i plan on using INDEPENDENT 4X threaded tube inserts that fit the heims and the insert go into any 1" I.D. D.O.M. TUBING. i plan on makeing them 40" overall length. at the axle end i will a set "univeral" bushing. when i go offroading i go all out make it or break it so i want ladder bars that can take some serious ABUSE. i plan on chromemoly of course!!

so i guess my real questions are:

should i use box tube or round tube?

since i want the I.D. to be 1" what outside diameter would i want?
how prone to bending would this be? I WANT STRENGTH

things to consider is that the ladder bars would both act as the upper and lower control arms and will be one setup, with of course cross braces

another thing to consider is the length of the ladder bars as the stress that will be placed on them so i want some material that won't be to easy to bend while bashing around on rocks and imports haha.

Thanks.

what do you mean by ladder bars?

are you refering to a traction bar for leaf springs that uses a shackle on the vehicle side?

no i'm talking about makes a ladder bar system for the front end to replace the control arms....i guess it would kinda act like a radius arm setup

gotcha, radius arms.

You will have a hard time finding square chromo tube, so you would be best off eliminating one or the other for consideration.

If you want beef, simple and cheap, 2x2 .250wall is great. If you want bling and lightweight 1.5 .250wall chromo would probably be good. Everything totally depends on design though, post up more on that.

don't waste your time with chromo unless your going to heat treat. It's not a significan enough gain in strength to justify the cost unless you have money laying around.

1.5" OD with 1/8 or 1/4" wall would be a good start, depends how hard your going to rail them. box will be stronger in bending but getting the rods ends is more difficult. Square is heavier though and you could run a thinner wall and not loose strength comapred to the round.

I consider 2" x .25" to be perfect for control arms. Especially for 40 inchers. The longer the arm, the more prone to deflection they are. There is a good discussion of this in advanced tech.

Why would you want to use a ladder design? A simple round tube is prove, stupid simple, and has less welded area that can fail. Ladders may have a bit more rigidity, of course.

Oh, and if you are looking for strength, I wouldn't be looking at 3/4" heims. They are known to break under suspension loads.

CRASH

i use 3/4" heims for my steering - FYI...

RE joints on my suspention...

so does any one now where i could buy some "universal" poly bushing for the axle side of the ladder bars- i want a set that has the the sleeve in the center , i want some that are made for at least a 9/16" bolt. thanks

I got a good deal on them from Mad4wd.com, they have them listed in the vendor section of the Pirate board also

jeep_87_cherokee said:

so does any one now where i could buy some "universal" poly bushing for the axle side of the ladder bars- i want a set that has the the sleeve in the center , i want some that are made for at least a 9/16" bolt. thanks

Click to expand...

Bad idea to use poly bushings on the axle side of a radius arm setup.

You really might want to think your suspension design through a bit more before attempting it.

Try searching on this site for "radius arm" or "suspension link".

This is how I did mine

www.4x4getaways.com/longarms.htm

While these are technically long arms, the same concepts apply. I run chromo for strength and I like the way it welds. The tube size is on the small size but has taken all the punishment I could deliver them.