Roofrack measurements

[David]

Stefan

Try getting some Citi Golf door trim from a scrapyard. You slip it over the 'feet' of the rack so it protects your Patrol's gutter.

trim.JPG (32.7 KiB) Viewed 1493 times

It is cheap and works great - I have used it for all my roof-racks

[SRXy]

Nice tip David thanks!

[Stefan]

That's a great idea, thanks David!

I've also spoken to the guys at Maitland rubber mouldings and it sounds like they may also have something that could fit over the foot section as well as the 'clamps'

[ricster]

Stefan, what line of work do you do that you know how to operate Sketchup like that.... Mooi man !!!

[davejones]

Anybody has an opinion on the following:

Full-length gutter support on the roof rack (like the Hannibal); some say it better as it can support more weight, some say it does not allow flex and can therefore crack therefore rather have connect to the gutters at various points.

My opinion; maybe in a car like a defender would there be some flex; I cant imagine much flex taking place with a patrol

[JG Shields]

I agree that it is hard to imagine flex on a Patrol. However, I did see a Disco 2's windscreen cracked while in a twister. It made me thought.

I believe that the solid bar spreads the weight better across the entire gutter, especially when fully laden and the vehicle hits bad road where G-force starts to come into play. It will surely provide better protection against gutter failure.

The roofrack obviously has load capacity limitations by design The "more weight" it can carry theory therefore does not carry much weight for me.

[Russ Kellermann]

Dave this is a question i also wanted to ask here, as i too have herd conflicting reports. Its a given that a defender flexes and contorts during articulation, alot to do with the design and body material made from Aluminium, but something i've never asked ... Is a Disco also Aluminium, i've never thought about this.

In regard to the long "feet", I agree that the long foot will help stefan distribute the load evenly along the rails, but surly if there IS slight flex somewhere, it will flex at the weakest point, which could then be the at the joint of the feet to the rack ? i'm just spitballing here, looking for some engineering advice to aid Stafans build integrity. Would it be strange to consider only laying the long foot between Clamp 1 and 2 , then the next one between 3 and 4 , leaving the middle feet without the bridging foot and in tern, allowing some flex. This means that you will still have 100% of your rack weight distributed over 66.6% of your gutter rails (if your clamps are evenly spaced).

I hope this makes sense, it started getting confusing when i brought out the maths equations, Which, are probably wrong anyway!!! it late and i'm buggered.

[Saltman]

My opinion; maybe in a car like a defender would there be some flex; I cant imagine much flex taking place with a patrol

Don't you believe it!
I made a 12 mm marine plywood "plank" that bolts down onto the Y61 floor behind the rear seats. There 14 bolts that keep it in place. On top of the plank I bolt and strap down all my equipment. The entire setup is very sturdy and solid when loaded. HOWEVER, when empty there is a lot of flex! The plank lets me know through a series of noises that it is flexing - over speedhumps, potholes etc.
I also notice the flex in the rear through the chafing of the rear doors - if they are not aligned 100%, you will get that feedback. Strangely the car is very quiet when loaded!
OK, I must add that the car has a 2" OME suspension kit, which does affect the suspension travel.

I have the long (either 2,2 or 2,4m) FR Windcheetah Roofrack and as long as you position it as far rearwards as possible, there is little windnoise.
Mine has the short feet (4 on each side) and all I did was use insulation tape around the base where it connects onto the roof. I was advised NOT to use a rubber U-shaped protector. FR sold them and halted it about 3 - 5 years ago as the Roofracks tended to shift under load on these feet protectors. This according to the Safari Centre salesman where I enquired about feet protectors to protect the car's gutter.
The insulation tape worked very well on our 7000km Botswana trip in Jun-Jul.

[JG Shields]

I want to support Saltman with regard to the gutter protection.

My solid foot is a 25x5mm flatbar, stretching across the length of the gutter. On the inside of gutter stretches the rubber lining attached between the beeding-trim and gutter plate itself. The flatbar foot fits very tight into the gutter. There is no room for additional rubber linings/strips. I also line the full length of the flatbar foot with duct tape which I replace every time I put the roofrack on. It works 100%.

I was also advised not to use rubber between the foot and the gutter. The rubber tends to de-form under the load, eventually being squeezed out of position which results in the tie-down brackets to loosen.

As far as the roofrack's effect on vehicle flex are concerned, I think we are over concerned. Any well tied roofrack, irrespective of the foot design, will have an adverse effect on the flex to a more-or-lesser degree. However, in practice we do not often hear of roofrack/body flex related problems out in the bush. In fact, I do not know of any. What I do know for a fact is that we overload our roofrack ito the design limitations and specs. In my mind the emphasis is on the load-spread accross the entire gutter structure, rather than worries about the "debatable" adverse effect on flex.

[Stefan]

Thanks Cedric, I'm an electronic engineer, I find scetchup quite easy to use, all one needs to learn is a couple of 'tricks'

My reason for the solid feet is purely for more even load distribution and to prevent stress points on the gutters. In my opinion, the greatest amount of flex whould occur in a twist situation, i.e. unequal horizontal movement between the front and opposite rear corners (left front & right rear & vice-versa). As the Roofrack is not a solid construction (slats with spaces) I believe it will allow sufficient flex.

That leaves the attachement of the feet to the rack as the potetially "weakest" links, for this I want to attach the feet to the rack by means of 2 bolts each which should provide a measure of movement, redunancy and ease of replacement if something does go wrong.

My gutters already have a "rubberish" strip on the inside so the insulation tape may be an option, but I'm not a big fan of the sticky gunk that often gets left behind. I still need to speak to the chaps at Maitland rubber mouldings to get an ideal solution, I'm thinking maybe some kind of thin "teflon" strip to use under the feet and on the clamps that hold the rack in place.

Would it be possible for you guys with roofracks to post a "side-on" picture of the rack fitted to your Patrol? (To get an idea of how you space your feet and how far back your rack is fitted) If you can also post a close-up of a foot and how the foot attaches to the rack, I'd really appreciate it.