CASC tech specs, which I feel are very reasonable, suggest that roll bar
mounts to sheet metal should have a metal plate of say 24 square inches (4"
by 6"), of .125 steel, with a matching plate under the mount, so that the
sheet metal is in a sandwich of .125" steel. The plates should be bolted
together with four 3/8" grade 5 (minimum) bolts per plate. A very good
suggestion is to install a lower cross-member between the legs of the main
hoop as close as possible to the floor, making the hoop a continuous circle
and strengthening the floor pan against side impacts.
If the car has a perimeter frame then mounting the cage to it makes a ton
of sense. If the car is unit body or a backbone frame, then mounting to
sheet metal begins to be the best way to go. Using common sense is key -
the frame has to be mounted to *strong* parts of the car to be of any use
whatsoever. Same goes for seats and belts. One way to imagine the roll
cage is as the "center" of the car. The driver is inside the "center" and
the car is bolted to the outside of the "center". The cage's job is to
keep everything outside out, and to keep whatever is inside in. So you
build a cage that just naturally keeps both the car and other cars, and the
ground, outside the perimeter of the cage and keeps you safe inside.
Brian
At 02:03 PM 03/23/2000 -0500, Joseph_Chimbolo@hyperion.com wrote:
>Rollbars, From what I have seen the Autopower bar is good. Installed to
>sheetmetal is done all the time. The more bars distributing the load the
>better. However, I am not a pro fabricator, but mounting directly to a
>chassis
>is always better. I think most professional car builders will ask you one
>simple question, "What is your life worth?". Right now you have a basic
>hoop,
>not much of a hassel to change. If you have the resources, put in the welded,
>chassis mount cage. Better is better. Feeling safe in the car knowing things
>are done properly will give you an extra measure of comfort when you decide to
>try that "late braking" move you just read all about.
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