Roll cage tubing question

#1

Anybody know the regs on tubing size when using 4130 chromoly? NASA regs reference mild steel / chromoly but they give only dimensions for mild steel. Seems that chromo cages with 1.5" diameter have .083 sidewall. Is that the size to use?

#2

I suggest you call NASA National directly. Their number is on the webdsite.

www.nasaproracing.com

Carter
’79 Hobie 16 sold a few years ago

#3

I think I have found the answer - 1.5 inch tuding requires .120 or greater sidewall thickness. Now I just have to find a few short pieces to add to my cage, whick is 1.5" x .125 sidewall. This is a custom made bolt in cage that fits very tightly against the roof and door frames and does not block the headlight switch. It is really beautifully crafted and I am hoping that by this time next year I am able to duplicate it for the next project car. Perhaps I’ll even be able to offer them for sale, it seems like a great alternative to leaving your car with a custom builder for several months. And the cage could easily be welded into the car. I’ll try to post some photos once I have completed the addition of second driver door bar and possible foot well protection.

#4

I think I have found the answer - 1.5 inch tuding requires .120 or greater sidewall thickness. Now I just have to find a few short pieces to add to my cage, whick is 1.5" x .125 sidewall. This is a custom made bolt in cage that fits very tightly against the roof and door frames and does not block the headlight switch. It is really beautifully crafted and I am hoping that by this time next year I am able to duplicate it for the next project car. Perhaps I’ll even be able to offer them for sale, it seems like a great alternative to leaving your car with a custom builder for several months. And the cage could easily be welded into the car. I’ll try to post some photos once I have completed the addition of second driver door bar and possible foot well protection.

#5

Sorry about the double post, I was yawning when I hit submit button and that caused a double tap.:blink: