DIY Fairing for roof rack. Would like advice.

[unabashedpraise]

I have a roof rack that I bought brand new a few years ago for $5. It's not the most 'expo' rack out there and I think it looks kinda funny on my zj, but it's what I have so I will work with it. Due to the rack mounts and the roof rail height it sticks up higher than I would like, but I am going to use the space under it for storage of a camping table.
I have test fit a fairing made of cardboard to cut down on the howling and to hopefully help with weather and mpgs. As you can see in the pic, the front slopes quite a bit. This fairing is going to be pretty big and I will probably be making it out of plexi.




I will use some u bolts on each of the four corners to attach the slanted piece. I may have the u bolts sticking out of the top to use them for cargo attachment points. Or I may just use something to use as a spacer to lift the top of the plexi off the rack about 1" and use the rack for cargo attachment.

My question is how do I join the two pieces of the fairing? I was going to use a u bolt with some sort of flat extended piece to attach the vertical fairing to. But I was also thinking about making it so that the fairing could rotate up if I had something longer to fit under the rack. The vertical faring can not permanently extend too far forward as it would block the sunroof from going up.

I hope you guys can make sense of this post!

 

[summerprophet]

Rather than building it out of 2 pieces, invest in a heat gun and just bend the plastic. I would google the type of plastic before you buy it as some will not bend, and other becomes brittle.

Also, I wouldn't make cargo attachement points like you have drawn, as the U-bolts may rotate and break your windscreen. If it was me, I would use P shaped pipe clamps, a rubber or nylon washer and a suitably sixed carraige type bolt & nut with Locktite.

Pipeclamps like these: http://sell.lulusoso.com/selling-leads/1947096/PVC-coated-flexible-conduit-pipe-clamp.html

If there is a plasics supplier anywhere near you, you should be able to pick up ABS for 5 or 6 bucks. I can attest it is easilly heat moldable....... but cutting it to shape is tougher. Rotary tools (dremel or router) will work, but for me, even a jigsaw on the slowest setting just heated up the material and it re-welded itself behind the blade.

 

[Mobryan]

Redneck plastic bender- find a piece of tube/round stock that matches the radius you want in the plastic, heat the metal with a propane/MAPP torch, then drape the plastic over the tube. Works kinda like a metal brake, only for thermoplastics. Can also make 90* bends with a piece of angle iron.


Matt

 

[BrandonS]

Heat gun as mentioned. I made a fairing for my homemade roof rack and used plexiglass and used a heatgun to mold it around the corners. Additionally, instead of the ubolts, you can use automotive trim adhesive to attach it. it's like a superduty double sided tape. It's a little bit cleaner of a look since you won't have holes and clamps sticking out.

 

[unabashedpraise]

I've used those rubber coated clamps in the past, good thinking. Much cheaper too! U-bolts are out of the equation.

I like the idea of using a heat gun and bending the fairing, but at the same time I would still like to remove or fold the lower fairing up if needed.


Anyone else have an idea of how to join the two pieces? Maybe a piano hinge?



I took a research break while writing this and found the answer! http://www.mcmaster.com/#piano-hinges/=mg53sm

Now if only I can find one local for cheaper. Seems suppliers are limited and are a bit hard to find.

 

[Mudy_Ovl]

You can buy piano hinge at the large home improvement box stores. Can't recall the price though. That's where I bought some when I built my storage drawer/sleeping platform.

Best of luck,

Chris D.

 

[GhostRing]

Then with the piano hinge, you need to figure out a way to lock it in place so it doesn't risk flapping around at all...
I personally can't think of a reason to remove just the lower portion?
Just get the fires going and form a sheet of HDPE or something - way more fun than a bunch of screws.

 

[Revco]

I think I have that same exact rack, and it has a fairing that I'm not going to use since it's being mounted on a bed rack behind the cab. You pay the shipping and you can have it. I'll get some measurements and pics tomorrow.

 

[bat]

Get scrap piece of abs plastic easy to bend and already black

 

[apalmer]

On a whim, and in about 20 minutes only armed with a box cutter and zipties I made a faring out of a couple campaign signs (the kind that get stuck in your lawn) and it lasted two years.

You could probably use that as the backing of the the "hinge" area, or you could make the whole faring out of it. Easy to cut, cheap, and durable.

 

[digitaldelay]

I would suggest you have the Lexan (not Plexi) bent at your local plastics fabricator. They have bending irons and can cut, router and bend it to your specifications quite easily.

Another option would be to purchase your own scrap of Lexan from them. Cut it yourself in two pieces and join it with vinyl hinge (also available from a fabricator).

Maybe try someone like this:

http://fabplastics.com/

Jason

 

[Mark Harley]

Find a local fab shop and have a piece of aluminum cut to size and bent to the radius you need.
Use quick fist clamps to hold it on.

"I think with your design when you open the sunroof it will create a vortex inside the cabin"

 

[unabashedpraise]

Update. I priced the materials I would need and was brought up short by the price of lexan, yikes! This fairing would cost me a lot more than any savings in mpg's with the amount of time I leave it on the jeep. Sooooo I decided to do some woodworking instead. I had some 1/4" plywood lying around and decided it would make a good fairing. I cut it to fit and did some light sanding followed up by some a few coats of spray sealant I had lying around. Because I know this plywood tends to warp rather quickly I wanted to make sure it is sealed very well and also thought the sealant might help the wood from soaking up the paint. I will follow up the spray sealant with some porch paint or maybe marine paint? I haven't decided what color to paint it yet. Because it is so big I was thinking black to match the rack, but don't want to limit my options. Maybe I can get the wife to paint the Expo decal on... I also picked up some rubber coated pipe clamps and nuts and bolts for attachment.

OR

My brother in law says he has a thule fairing that he used on his Jeep Liberty with his bike rack that he offered for free. We aren't sure if it will fit and I don't know when I will have a chance to get it. Obviously this is the route I would like to go, but if it doesn't cover the entire face of the rack is it worth putting on?



Another thing that I want to do it do some modifications to the rack itself. If you look at the first pic the mockup is not sitting directly on the main rails. That is because the smaller tubing that makes up the basket is not welded to the bottom support like the outside arm. Instead they bent the tubing and then welded it making it sit higher than the frame. You can kinda see it here.

What I want to do it cut the tubing and bend it down and re-weld making the tubing and the frame slope on the same plane. I'm going to look at some paint tonight or tomorrow.

 

[unabashedpraise]

Mostly finished

Mostly finished the fairing, but in looking at it I realized I should have rounded over the front corners it match the rack.

I used my jigsaw to cut the front tubes, crimped them, sealed them with silicone and bent them down out of the way until I can weld them. I may just leave them seeing as they aren't really needed for my application and serve no purpose. I have since sealed the bolt heads and painted them as well.









Pros:
CHEAP. Already had the wood and tools so I only needed the fasteners ($8) and a quart of paint ($9). I only used about 1/4 of the paint so I can use it on other projects.
Easily replace/repairable.
The fairing makes a world of difference in the noise level.


Cons:
Looks like painted wood. I should have sanded the fairing down to a nice 220 or so before painting. I didn't realize the grain would show up so much with brushing on the paint.
Doesn't look as "cool" as the aftermarket fairings.

 

[Doorplease]

Did it end up helping with mpg?