Opinions needed!

[jimbbski]

I am in the middle of fabricating a roll cage for my ITA car. Someone else is bending the tubing to my specs. and I am cutting, fitting, and will then weld the tubes together. I have experience welding, gas, MIG, and TIG so that's not an issue.

I will be adding gussets to all of the major joints and adding a few additional tubes to the cage when the main part is completed.

What I am looking for now is suggestions & comments on what I have so far. The connection from the forward support to the "halo" bar is my main concern. Will it pass tech? Use the attached link to view. The round disc under the main hoop is just there to raise the bar an extra 3/16 of an inch. It will be removed before I weld the tube to the floor mount.

Thanks;

http://share.shutterfly.com/action/welcome?sid=0EctHDVw5cMWFf&emid=sharshar&linkid=link5

[joeg]

Looks very nice.

Gussets are only "recommended" and for IT, they are limited in thickness.

You do not "need" gussets, although I use them.

You can also use a short piece of tubig to act like a gusset, since there is no limit on additional tubes within the cage structure.

[lateapex911]

I see no reason why it wouldn't pass tech. Of course the weld must be complete, and the tops can be tricky. If your cage is on boxed supports, then it's easier, but if not, a hole saw to the roof gives the needed access.

[gsbaker]

Just as an FYI, gussets will dramatically increase both the stiffness and the strength of the joint.

[betamotorsports]

I've heard good and bad things about flat plate gussets and I generally don't have an opinion either way. If a customer wants me to add flat plate gussets to a cage I build I'm happy to do it, but they need to specify where they want them. I generally avoid putting a gusset inside the plane of the joint (between the joint tubes) because a bridge building engineer friend of mine said that creates a point load on the tube at the tip of each gusset. He suggested placing the gusset on the outside of the joint along the centerlines of the two tubes making up the joint.

I do install short diagonal tube lengths to reinforce the upper door hoops and other long span upper cage elements. I also like and use Joe's wrap around tube gussets.

[jimbbski]

Thanks;

I do plan on using some short pieces of tubing to trangulate the joints. Sort of a gusset that's not a gusset.

I have holes made in the floor in front and the boxed mount you see it the pics. That round disc is covering it up. It should alllow me to first tack the cage together and then "drop" the cage legs down about 3 inches for the roll bar hoop and much more for the front down bars. More then enough to do a 360 deg weld on each joint. Once that's done I just raise the cage back up and weld the legs to the floor mounts.

I also have all of the glass removed. I learned the hard way when I had to add door bars to my ITC car. It was built before SCCA required door bars. I ended up with pitted windows from using my MIG.

This is my first full cage build. In the past I only had to add a bar or two as in my ITC car, my 93R came with a cage when I bought it.

[chuck baader]

My only comment would be about the mounts for the main hoop. I would rather see the tubes come to the floor and be tied into the intersection of the three panels at that point. That way, they are tied to the structural perimeter box. Chuck

[betamotorsports]

I ended up with pitted windows from using my MIG.


Next time buy a roll of 3M Weld and Spark Deflecting Paper - part # 05916

[Greg Amy]

First thing I thought of when I saw a thread entitled, "Opinions needed!" was

"Boy, did YOU come to the right place...!"

:happy204: