Dealing with "roof ribs" in mobile installs

[loosecannon]

Hi all,

I will be doing an install on a van in the coming months, and of course, it has one of those protruding ribs right in the center of the roof that runs the length of the vehicle.

the plan is to put the antenna toward the rear of the roof but im going to have to get creative in order to deal with this stupid rib.

This mount will have to be able to deal with a 102" whip being put on it and driven at highway speeds, which means i'll also be adding some plate to the underside.

The rib in question is 1 inch wide and the top of it sits about 1/2 inch above the regular roof level.

my initial thought is to use a stud mount similar to this:


the smaller diameter barrel nut seems to be the right fit to sit atop the rib, and of course i'll have to get creative with the underside in order to be able to tighten everything down without crushing the rib.

that's as far as ive gotten, and am hoping that others have had to deal with similar installations and might have some ideas to improve upon mine.

im not married to this idea but i am also not really looking to drill 5 holes in the roof of the vehicle to accommodate one of those big puck type mounts.

all ideas are welcome, even bad ones!

thanks in advance,
LC

 

[Eldorado828]

Hi all,

I will be doing an install on a van in the coming months, and of course, it has one of those protruding ribs right in the center of the roof that runs the length of the vehicle.

the plan is to put the antenna toward the rear of the roof but im going to have to get creative in order to deal with this stupid rib.

This mount will have to be able to deal with a 102" whip being put on it and driven at highway speeds, which means i'll also be adding some plate to the underside.

The rib in question is 1 inch wide and the top of it sits about 1/2 inch above the regular roof level.

my initial thought is to use a stud mount similar to this:
View attachment 59189

the smaller diameter barrel nut seems to be the right fit to sit atop the rib, and of course i'll have to get creative with the underside in order to be able to tighten everything down without crushing the rib.

that's as far as ive gotten, and am hoping that others have had to deal with similar installations and might have some ideas to improve upon mine.

im not married to this idea but i am also not really looking to drill 5 holes in the roof of the vehicle to accommodate one of those big puck type mounts.

all ideas are welcome, even bad ones!

thanks in advance,
LC

No advice from me, I'll be paying attention to this thread because I'm trying to help a buddy with his and same issue. He wanted to use his styker mag mount but too wide, the middle rib, and it's an alumina Ford.

 

[M0GVZ]

By the time you've put in plates and all that nonsense to find that it'll be great resisting movement front to back but not left to right unless you're going to make plates with the same contour as the roof, using a puck mount would've been much better and easier.
Breedlove Mounts do do puck mounts that are a single hole. Their 2" and 3" pedestal mounts are single hole.

 

[loosecannon]

Im with you M0GVZ, i would love to use a puck mount, but that stupid rib is right in my way.
if only breedlove made a puck mount with a dado running through it for use with a roof rib.

When i say plate, i mean a piece of plate that is about 30" x 16" or whatever fits in between the two adjacent roof trusses and it would follow the contour of the roof.

as of right now, it kind of seems like im trying to make something work that doesn't want to work, and usually when i do that, there is a better idea out there that hasn't occurred to me yet.

Since i happen to have some access to a mill, i might just buy the breedlove puck mount and cut a dado in it myself. hmmm...

no matter what though, im going to use plate on the underside as this is a newer vehicle and the metal on the roof is super thin.

thanks for the advice so far.
LC

 

[Handy Andy]

IT depends on how "wide" that rib is.

These are tapered too, so the flat of the rib would just need a flat stock galvanized to fill that gap of the rib. - usually nothing more than a 3/16" thickness and you're able to run it along the channel inside - just use a piece of electrical tape to keep the burrs on that flat stock from scratching the underside primer paint.

That would prevent the "dimple" effect from the crushing - the flat stock fills that.

The harder part is the side-to-side twist and flex - that requires the crossmember to get some kind of bulkhead stock to reduce the buckling that the roof would do in the roof-panel sheet.