- 1). Measure the interior (or exterior) dimensions of the car where the roll cage will be installed using a tape measure. Use these measurements to design the roll cage. In this case we will build a 30-inch high and 70-inch wide roll cage bar.
- 2). Add the width to two times the height you have measured to come up with one length for the roll cage bar. In this case the total length is 130 inches.
- 3). Cut a 2 1/2-inch (or thicker, up to 4-inch diameter pipes can be used) pipe to the total length you came up with in step 2 using a metal saw or pipe cutter.
- 4). Insert the pipe into a brace so a little more than 30 inches of pipe are extending out away from the vise. The additional space is to allow room for the bend that will be placed into the pipe.
- 5). Heat the area of pipe near the vise and, using a bending tool, bend the pipe at a 90 degree corner angle. Or, insert the pipe into a metal bender at the 30-inch mark and perform a 90-degree bend, if you have access to a metal bender.
- 6). Repeat steps 4 and 5 on the other side of the pipe, making sure that the final, total length is still the 70 inches you measured to begin with.
- 7). Let cool and then rough sand the exterior with 320 grit sand paper, prime with automotive primer and finish it with a coat of automotive paint.
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