My cage is bolt in.. And I have 3 months with which to mess around so I want to make the plates bigger and weld the cage into my car.

Where can I get some metal ( about 2mm Thick) and place it under my current footprint of the cage. And then weld and bolt the pieces together..

Any thing good/bad about this ?

Thanks
~J

 

Any local steel supply should have what you're looking for.

Here's how mine turned out:

 

Be careful. If the material used isn't thick enough, the cage could be illegal.

From the NASA GCR

15.5.14 Mounting Plates
Each mounting plate shall be no greater than 100 square inches and no greater than 12 inches or less than 2 inches on a side. Welded mounting plates shall be at least 0.080-inch thick. Plates may extend onto vertical sections of the structure. Any mounting plate may be multi-angled, but shall not exceed 100 square inches total including vertical sections.

15.5.14.A Mounting Plates – Bolt-In Cage
The attaching points of a bolt-in cage to the body must use reinforcing plates to
sandwich the body. At least three (3) bolts are required for each bolt-in plate and the plate must be at least 3/16 inch thick. All hardware must be SAE Grade 5 or better with 5/16” diameter minimum. All nuts must be held securely by a locking system such as safety wire, lock washer, Ny-lox, or jam-nuts.

 

My plates are the same thickness as the original Kirk plates so they are within the rules for bolt-in cages. However, as long as you don't remove the original bolt-in plate, I can't imagine that anything you put under that would matter. If your original 3/16 plates that come with the cage are welded over 1/16 larger plates, the total welded plate is 4/16 so you're good. I guess mine is closer to 6/16. Horay for overkill!

 

Travis,
The info was meant for the original poster. "2mm" plate.

 

Right, but I was saying that if he kept his original legal bolt-in plates still attached, it didn't matter what thickness he used under that plate since it just adds to the thickness. At least, that's how I read it.

 

Hmmm. OK, I see what you are saying.

Here is some rules nerd questions. If you are converting to 'weld-in', shouldn't the plates meet the min. 'weld-in' specs of .080?

-or-

If extending the plates of a ' bolt-in', shouldn't the plates meet the min. 'bolt-in' specs of 3/16", for the whole plate? In addition, wouldn't you need to retain the min. of three bolts of 5/16" Grade 5 or better per plate?

 

Here's how I would answer those questions.

If you're cutting off your bolt-in plates and are going to weld new plates to the tubes and weld these plates to the floor, you must meet the weld-in thickness.

If you're cutting off your bolt-in plates to weld on new bolt-on plates to the tubes and then bolt that down, your new plates must meet bolt-in thickness

If you're going to weld your bolt-in plates directly to the floor, they already meet the weld-in thickness.

If you're going to sandwich a larger plate between your bolt-in plate and the floor, or if you're welding larger plates onto the existing bolt-in plates, it doesn't matter what thickness you use because you're not removing your current legal plates (simply adding to them).

At least, that's how I read the rules.

*edit*

Oh yea, and if you're not welding the plates to the floor, you need the min 3 bolts per plate and a backup plate, just like the normal bolt-in rules. My first pic with only two bolts was an "in progress" pic.


[Modified by travis, 1:20 PM 3/8/2003]