Square or Round Links?

Need to figure out the plus minus of square versus tube radius arms! Any comments?

Round 7075 solid aluminum for the win. StinkyFab.com is a sponsor here, or IronMan4x4fab.com, or WideOpenDesign.com. I have a custom RockCrawler 3 link with aluminum links but I don't know if they are still available. I remember seeing am Ultra4 unlimited buggy that broke all 4 steel links at the welds in qualifying at Glen Helen. Rear bypasses and coil-overs, sway bar links and driveshaft all bent.

It seems to run about $100-150 a link without rod ends which isn't bad especially if you were to pay for a welder to weld tube adapters to DOM tube.

I hear you but I have 2 wire feeds one stick and two sets of torches and a plasma cuter. I have built all my own stuff so lifts and conversions! I was asking my friend which is an engineer about the round or square tubing and he said round and proceeded to explain why. 20 minutes or so of hearing him explaining why radial strength is stronger against compression force I said its not holding anything up. The force is lateral and increases and decreases at different degrees of articulation. I explained the strength I am looking for is bending force coming off a rock or boulder. He then said the same size thickness in square is stronger than radial! My only issue is I have 1/2"wall x1 1/2" dom versus 5/16" wall 1 1/2" square tubing! I would imagine that either is equal inn strength with the dimensions I have listed but is it sufficient? The links on my 4x4 van I went with 1 3/4" dom but I do not remember the wall thickness? If anyone has pro's or con's on either please let me know!

I would go with square. It's a lot cheaper, and the strength difference is not enough to worry about.

The square is going to be stronger for rock impacts.

Another thing to think about is wall thickness vs outside diameter. I larger OD will resist bending better them a thicker wall smaller OD. Personally, I wouldn't run anything less then a 2" OD and 1/4" wall for a LCA. I know people with 1.75x0.375 LCAs that have nice bows in them. I have 2.25x0.375" and 2x0.5" for my lowers. Square vs round is all about your budget but I know a couple of 2x0.25 square lowers that are holding up fine

I wouldn't use 1.5" anything for lowers, uppers yes. Like Ross said 2"x.25" for lowers. I've been running square lowers for years with out issue.

^^ These guys go full retard. I mean that in the best possible way. I don't think, though, that everyone who is putting an aftermarket arm on the Jeep needs 3/8 or 1/2 wall. Rubicon Express sells arms at 1/8" wall, I think, any most people are happy with them... so it's all about intended usage.
If your sheet metal is intact and you want it to stay that way you probably aren't doing the sorts of things that are requiring that heavy a material.

yossarian19 said:

^^ These guys go full retard. I mean that in the best possible way. I don't think, though, that everyone who is putting an aftermarket arm on the Jeep needs 3/8 or 1/2 wall. Rubicon Express sells arms at 1/8" wall, I think, any most people are happy with them... so it's all about intended usage.
If your sheet metal is intact and you want it to stay that way you probably aren't doing the sorts of things that are requiring that heavy a material.

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1/8 wall is OK for short arms or uppers but absolutely not for lower long or mid arms regardless of how you wheel

I've seen more then one RE lower that's been bent and damaged 1/8" wall is fine for controlling the axle and such, its contact with rocks that it won't stand up to. I'll agree that my arms are slightly overkill, but I got great deal on it.

Another thing to think about is that the OP said radius arms. Having the UCA bracket welded to 1/8" wall arms could cause fatigue and failure of the tubing. I'd want a good solid 1/4" thick tubing to support the bracket and any rock contact.

I just built by new lowers out of 1/4th inch square tubing..... we've got a couple guy's in our club that even sleeved theirs with 1.5 OD heavy tubing making them an almost solid 2 inch piece of steel. Low weight is good weight.

Ive got square links, i beat the crap out of my rig.

Most others have pretty much said it. GO with the minimum thickness and pick what you want/can afford.
Huey Lewis said it .. It's hip to be square.

Well I have both 1/2 wall 1.75 round and square 2.0 1/4 with 1.5 3/16 to sleeve if I feel the need! Well I guess I'll flip a coin! Maybe make some spares out of the loser!

I'd look up "bend strength calculator" on google and see which one bends less for a given length & load.

Or just click here.

Spoiler: The square tube will deflect under half as far as the round stuff.

2" x 1/4" wall square

Either one is better than old Ford radius arms..

Johnnie Walker said:

Either one is better than old Ford radius arms..

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Funny you say that, I've been considering building a Ford RS suspension w/ D44 but that's on a 2wd project, would be a DOM stick straight across.
Are the Ford bits not very strong?

They are strong! The issue I had was I drilled/cut off the rivets that held the original factory shock tabs/mounts off. I did this a couple of years ago when I swapped the 9"/44 front from my 1985 V8 XJ to my 95 stock XJ. Prior to that those arms were on my 85 for 20 plus years! I decided to change the body mount points because I had made a new t-case mount & skid plate for the 95's Dana 300 and reduction box I had put in the 95. I did not want to mount the stock arms under the chassis like they were on the 85, so I cut the arms threaded ends and then cut shock tabs & rivets holding them on, off! The arms are like a tapered I beam so I split/cut the arms where the flat top and flat bottom came together with the upright part of the beam and slide round tubing down the cut I beam. I did this so I could bend the ends of the tube upward and out for a better Johnny joint flat mounting point at the t-case cross member mounting point. I drilled and spot welded all the way to the end where the RA's ended in the tube. It came out great, excellent angles and articulation. The problem was that after inserting the tube on the arm and welding it slowly to prevent temper reduction the tube did not butt up to the "C" part of the arm therefore leaving the two rivet holes unreinforced. Since the arm was now reinforced from the point of where the tube began back to the JJ's all the torsional and lateral flexing of the arm was concentrated on about 8"s of the radius arm where the rivet holes where rather than the 30"s or so of the original length. Not to mention the shock mounts where placed just forward and on top of the arm where the holes were! The flexing caused the arm to fatigue and the RA's broke where the rivet holes were! In hind sight I should have ran the tubes all the way to the "C"s edge. I thought since the RA's thickest section was right behind the C's it would be ok!
Would I do it again? YES just the way I said, running them all the way to the C's. Why I am not doing them again? Because I gave away a spare set of RA's I had, to a guy that bought an extra Ford 44 I had laying around! I also have square and round tubing as well as the original JJ's and 2 spare 1 1/4" heims from my Van laying around! I also feel that at some point I am going to go bigger and MAYBE coil over so it is time for a 3 link!