<cr>
I am planning on installing a 4-point interior cab roll cage in my 53 F100 during the restoration process. That has led to a question I have been pondering for sometime.

I realize the cage should be secured to the frame if I want the maximum protection. At the same time though, that leads to a noise problem and since the rig will be a daily driver, I would like to eliminate that issue.

I'm looking for mounting suggestions. If you have experience in this area, an idea, or have seen how people have attack the problem, I would appreciate your input.

 

one way of doing it, is to have the interior mounting points welded to a square flange drilled with a hole in each corner. This will bolt to another flange beneath the cab which is attached to the frame. If you use heavy gauge steel and grade 8 hardware this can be a very strong and safe method. In essesnce, the flanges "sandwich" the cab floor rather than having the cage itself pass through the floor. You will not have any noise issues. Although, if you bolt the cage directly onto the frame, all you have to do is install really thick bushings where they pass through the cab to reduce noise imo.

 

Youll probably have to have it built inside or assembled inside your cab, unless you got yourself some big doors. you didnt mention what type of cab you had, but Ill assume you have an extended, as that is what I normally see in F100s (at least here in Texas).

 

<cr>
Exactly the idea I had in mind and that got me to wondering.

The cab is mounted on rubber, isolating it from the frame. Although I don't know why it is mounted that way, I suspect it was to reduce the stress to the mounting points and/or to reduce the noise level. Needless to say, a solid roll bar mounting would eliminate the function of the flexible cab mounts.

Road noise, transmitted to the frame, was my main concern. As I was writing this though, I recalled the newer unibody car. The body is the frame.

All input is welcome !!

 

As far as I know, there is only one cab in 1953.

You're right about having to build it inplace. The project involves putting a 53 cab on a 56 frame and piecing together 3 boxes, to make one box. I'm going to call it a 1953 1/2 F100 . Everything has been stripped and I just completed the frame work. Next inline is a Volare clip. I have a long ways to go and I'm trying to think ahead. At my age though, thinking ahead can be difficult because you realize you are on the downhill slide. You know you may not get to finish it because you may run out of any time.

You have to love this site. So much experience and knowledge you can tap.

 

One of the reasons for bushings between the cab and frame is so the cab flexes a lot less when the frame flexes. The cab is suppose to compress the bushing. Even on a fully boxed frame, it can still flex a lot and if you have solid mounts on a vehicle with a roof you can rip the cab itself. Not to mention the rubber cuts down on noise and vibration.

You can still tie the frame and rollbar together good enough for a daily driver by squishing the plates and bolts between poly washers and insulators. US Plastics carries an amazing selection of solid block and solid tube gray/blue/black nylon that you can use.

I *think* for the NHRA rules for 7 second cars you have to tie directly to the frame. I think that would be overkill for a daily driver that will not see 100 mph and I see no reason not to use insulators.

On my truck I am running 3" x 1/8" x 6 ' channel under the body, bolted directly to the frame with 1/2 grade 8, and attaching my roll bar to that. It will be insulated between the rollbar and 3" channel.

I have been experimenting with that size on my bed and have had close to one ton in the bed and the 3" channel does not flex at all and with just one 1/2" bolt at each attachment point it has not moved at all.

The only drawback is weight. The 3" channel is about 1/4 thick at the radius points and adds about 40 pounds more of steel to the vehicle.