benefits of c channel vs angle iron for frame rail reinforcement

[Kejtar]

seeing that I will have a lot of work when I get the new XJ I am trying to plan everything out (might even start working on some fab pieces ahead of time). Anyways, frame rail reinforcement: how much do I gain from going to C channel vs getting decent angle iron? The angle iron (well fitted) would go on the outside and protect the underside (with a small lip maybe going over towards inside). Also the rock rails would be welded to the angle iron as well.

 

[Lawn Cher']

Channel would be stiffer, but also heavier, assuming same thickness. I went with angle because the inside of the frame rails has some overlapping seams near the transmission crossmember that looked difficult to work around.

 

[Kejtar]

Channel would be stiffer, but also heavier, assuming same thickness. I went with angle because the inside of the frame rails has some overlapping seams near the transmission crossmember that looked difficult to work around.

Got any pics? how thick is the angle that you used? 3/16" more? less? how far did you go forward and how far towards the rear?

 

[IntrepidXJ]

have you seen this

http://www.projectxj.com/mods/frame.bracing.htm

 

[Lawn Cher']

Got any pics? how thick is the angle that you used? 3/16" more? less? how far did you go forward and how far towards the rear?

No pics yet, this was one of the things I did during my rushed buildup prior to missing Moab '03 and moving from NJ to MO. The XJ still doesn't have brakes, and just sits woefully in the garage. I think it was 3/16 or 1/4, 3x3 angle. I ran up to the LCA mount in the front and to the spring hanger in the back. I had to splice 2 pieces together with a vertical offset to follow the shape of the underside of the frame, trimming the forward vertical leg such that the horizontal legs overlapped by several inches with a flat spacer plate in between, then putting a flat plate across the joint in the vertical legs. I can take a pic tonight and e-mail it to you, if you'd like.

 

[OT]

Or you could post it on here for the rest of us too.

 

[Kejtar]

I can take a pic tonight and e-mail it to you, if you'd like.

Please do. Also did you weld or bolt?

Intrepid that looks cool. How are the welds holding up with impacts ?

 

[JeepFreak21]

If you're going to run long arms (or similar) you have to consider a strong way to attach the brackets/crossmember. I'd use channel between the front leaf spring hanger and the lower control arms because it's simple enough and provides a good place for brackets if you wanted to mount them on the inside of the "frame". I plan on doing angle pretty much everywhere else because the width of the "frame" changes several times and it'd just be a b!tch to do w/ C channel.
Billy

 

[Kejtar]

If you're going to run long arms (or similar) you have to consider a strong way to attach the brackets/crossmember. I'd use channel between the front leaf spring hanger and the lower control arms because it's simple enough and provides a good place for brackets if you wanted to mount them on the inside of the "frame". I plan on doing angle pretty much everywhere else because the width of the "frame" changes several times and it'd just be a b!tch to do w/ C channel.
Billy

No long arms in the forseeable future for me.... but then again I own a jeep which means anything is possible.

 

[Lawn Cher']

Or you could post it on here for the rest of us too.

I would have eventually done that, but I haven't established a picture hosting site yet. (No time like the present, I suppose.)

Also did you weld or bolt?

Well, technically there are 3 fastening methods holding the stiffeners onto my rig. I drilled holes to pick up the stock crossmember bolt locations, and modified my Clayton crossmember to bolt into said holes as well as weld into place. I also completely stripped the paint and undercoating off the frame rails and used liquid nails to glue the stiffeners into place along the entire length of the frame rail to get good distribution of loads... it acts like a laminated composite structure. And last but not least, with much help from CHW, we welded them to the frame rails along most of their length. So, if I ever decided that I'd like to change the design (which often happens) it is too late. Those biatches are stuck on there.

 

[xj92]

If you use C-channel, you pretty much have to use 4x6x1/4" tube cut in half so it fits up right. If you use angle you have more options. I used the C-channel. I'm glad I did, but it was a lot of extra work to get the inside portion of the frame rail welded up, removing brake lines, exhaust, etc. I have a thread on my buildup and some pictures here.

 

[IntrepidXJ]

Intrepid that looks cool. How are the welds holding up with impacts ?

Those aren't mine. Just thought I'd share the link with you.

 

[AzRick]

More pics here of what I just finished. I used angle iron the whole length of the "frame".
pics

 

[Kejtar]

More pics here of what I just finished. I used angle iron the whole length of the "frame".
pics

Do you have any more detailed pics on how yo udid the 2x6 into the rockers?

 

[JeepFreak21]

Do you have any more detailed pics on how yo udid the 2x6 into the rockers?

I have detailed pictures of the first half of the process if he doesn't. I'll do a writeup if I ever finish them.
Billy

 

[AzRick]

I posted this earlier, but it didn't come through.

Here's how I tied in the rockers to the frame. There will be two more per side, which will double as "feet" for the cage:

I don't have any more pics, but I modeled them after the fine URF design found on Jes' rig. I think he has some pics somewhere.

Rick

 

[Kejtar]

Thanks Rick
Billy... I'll take them pics Where are they?