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View Full Version : Cutting/welding RE trackbar and tie rod



nate
04-07-2005, 07:05 PM
I'm working on a steering setup and I'm curious. The RE junk is cromoly from what I understand. Can I weld this stuff without doing anything special. I think I'll need to shorten my track bar, and I'm going to probably use the RE tie rod as a drag link.

ATL ZJ
04-08-2005, 03:43 AM
Check out the topic of the week over on the PBB.. It's on welding, and the subject of welding cromoly and threaded inserts, for example, with MIG arose. Some were saying that it basically wastes the strength of the cromoly that you just paid for due to the brittleness of the weld, or how it compromises the material.. I'm too tired to go look it up, so you can. :mrgreen: Hope that helps.

nate
04-08-2005, 04:29 AM
That's funny that just about everyone on there says something different. One guy says, yes that's the right way, another no that's wrong. haha. I suppose do whatever you want if it holds huh?

Like my Lincoln book says pulling pentrates better than pushing. Everywhere else I've read just the opposite. Whatever I guess.

Nordic1
04-08-2005, 10:22 AM
On PBB I've seen several time (Yea I know alot of people on there contradict) that mid'ing cromoly is a bad idea and that you should TIG (I think) it if you can. AprilzWarrior Mig'ed my RE trackbar when I cut it down and it's been fine... If you were realy worried about it , you could sell your RE trackbar, pickup a small RE joint, a small poly joint, and some dom and just make a trackbar.

Kraqa
04-08-2005, 03:12 PM
i modded the track bar and it didnt' break where i welded it broke at RE's bends.

nate
04-08-2005, 10:26 PM
Oh, I'm not worried about it... just was asking it all. DOM is like $1 an inch here... we use pipe.

NorthernZJ
04-09-2005, 06:56 PM
A few notes about welding chromoly:

a. results depend on what type you want to weld, 4130, 4140, 4340, etc.

b. 4130 welds quite well

c. However, chromoly materials are important because they become very strong when heat treated... you would use 1020 or something if you didn't want to heat treat the material.

d. Any type of welding will locally remove heat treating which was already there.

e. When welding 4130 to 4130 you should use an appropriate filler rod with a TIG.

f. After welding 4130 the material needs to be normalized (welding causes residual tensile stress to be in the material... normalizing removes this and brings the material to a relaxed state). Then the whole thing needs to be heat treated as a unit.

g. Really though, in you garage and not a race car fab shop, you can weld 1020 to 4130. However, don't expect to get any advantage from using 4130 as the joint won't be heat treated for strength. Also failure due to fatigue loading might become a long term issue at the weld area. Most of the time though you should be fine... I bet rubicon express is using a 4130 track bar because they have a bend in it. Loading the beam in bending like that really causes high stresses in that area. I bet that is the limit safety factor point as Kraqa said he broke his at that point.

ALSO!!!! DON'T USE PIPE FOR MECHAINICAL PARTS!

Pipe is great if you want to build a fence, transfer gas or fluid. However, don't ever use pipe in a mechanical system like your truck suspension. Pipe isn't very strong at all! Here is a little info about strength...

Pipe - 30,000 lbs yeild strength
Square Tube - 50,000 lbs yeild strength
DOM - 65,000-70,000 yeild.

Pipe SUCKS!!! The material is also quite rough on the surface and isn't very consistant within the micro structure. This means that it isn't well suited for fatigue loading like parts in suspension systems! Please everybody... stay away from pipe! :smt003

nate
04-10-2005, 03:22 AM
Ok, I should have said tubing... like HREW tubing I guess. To me that's pipe.

Swamp boy
04-10-2005, 12:49 PM
I cut and lengthened my RE Trackbar about 3 years ago and have had no problems.. (Of course I am in mudd most of the time so my suspension doesnt do much articulating.. :smt003 )

OH and I try to stay off the pipe ... But that stuff keep calling me.... :smt003

NorthernZJ
04-11-2005, 12:47 PM
oh... good HREW tube is cool. Much better for mechanical applications....

Swampboy.... I kicked the habit but it kicked back! :rolleyes: