Roof Rack Design Input

[BlackWorksInc]

So as you guys know I want to make my own roof rack for my Rig, I picked up the Tube notcher today and was thinking about materials...

I was pretty set on 1.5" OD, .0625 (1/16") WT, ERW Steel tubing, my rough estimate on total material needed is around 70'.

That's about $350 in materials with a weight of about 70lbs.

Out of sheer curiosity I went ahead and decided to look up the weight difference for some Aluminum Tubing, 1.5" OD, .125 (1/8") WT in the same length, I increased the wall thickness to compensate for aluminum being rather soft in comparision to steel. Now the Aluminum comes out to about... 45lbs and about $330 for 70'

My question here is what do you guys think about the roof rack being made of Aluminum vs. Steel? I like the idea of shavin' about 30lbs, and the roof rack is probably not going to get the same abuse as say the front, rear, or sides of the vehicle. I also don't see 30lbs making that big a difference in contributing to the 4Runner being top heavy...

Here's a rough sketch of the current design of the roof rack for reference, its going to be roughly 6.5' x 4' to give you an idea. Blue is the lower portion of tubing and Red is the upper.

You're input is greatly appreciated! Also posting this on the 120 Forums.

 

[BReardon21]

Are you doing a fairing to deflect air? If not its going to be loud!!!

 

[blkexp98]

You may could switch to a oval with maybe a 3/4" - 1" thickness or just a smaller diameter tube for the center supports. That way you may save a little weight but the main thing is you could get it closer to the roof. It will make it harder to make but i also think the ones that are shaped to the curve of the roof look good. Are you going to be using anything to help close in the bottom? I can see that being an issue with smaller parts. If you wanted to keep it light you could get some sunbrella or canvas material that you could roll out when you needed it.

I've thought about an aluminum rack too and thought it would be a good idea (Im pretty surprised it was cheaper) but i cant weld so the cost stopped me there. No only considering the center of gravity you also should consider stress on the mounting points with the extra weight. 30 extra pounds is considerable i would think. I would think if you added a light arch to the cross bars that would allow you to use a smaller tube and it may hold a little more weight.

On the upper part in the front i think id bend the tube to follow the lines of the lower portion. It just looks like it would flow better that way. If you can bend the tube i think id follow the curve on the front of the roof line. Fiberglass may be a good solution to make a fairing if you decide you need one.

Hope that helps some and keep us updated

 

[BlackWorksInc]

The biggest issue with trying to match the curvature of the roof is that I have no clue what the angle of it is and how I would even try to make such a large radius.

 

[blkexp98]

How i would do it is get a piece of electrical emt and bend that to get the contour and then bend the real tube to match that. 1/16" wall tube is pretty thin and you should be able to bend a large radius. I dont know if it would work but you may could drive some rebar into the ground at an angle and make that the form (add for springback). Drop slightly larger pvc pieces over the rebar to help protect the tube. One end would be secured with rebar on both sides and the other end would be pulled around the "form". If necessary a smaller piece of gas pipe could be used as a lever to give more of a mechanical advantage. If necessary i can be a little more descriptive with the picture i have in my head.

Electrical EMT is pretty cheap and could work good to test out methods and looks.

 

[BlackWorksInc]

How i would do it is get a piece of electrical emt and bend that to get the contour and then bend the real tube to match that. 1/16" wall tube is pretty thin and you should be able to bend a large radius. I dont know if it would work but you may could drive some rebar into the ground at an angle and make that the form (add for springback). Drop slightly larger pvc pieces over the rebar to help protect the tube. One end would be secured with rebar on both sides and the other end would be pulled around the "form". If necessary a smaller piece of gas pipe could be used as a lever to give more of a mechanical advantage. If necessary i can be a little more descriptive with the picture i have in my head.

Electrical EMT is pretty cheap and could work good to test out methods and looks.

Yeah I am having a hard time visualizing that...

Truth be told though, a lot of the roof racks for sale, (GOBI, Yamika, ect) are flat bottom also and don't look that bad.

 

[darkie3495]

Yeah I am having a hard time visualizing that...

Truth be told though, a lot of the roof racks for sale, (GOBI, Yamika, ect) are flat bottom also and don't look that bad.

If you wanted to follow the curvature, a tube roller or tube bender could achieve it.

I measured distance between a level plane parallel to the highest point of the roof down to the roof itself in 6" increments to determine the curvature of the roof line front to back (Too bad i didn't do that from left to right.:ybrick and my fabricator just marked bend points and went to it.

Here are my old designs:

I agree with you, flat bottom racks look just as good so this might be a moot point.

If you can go with Aluminum, I say go for it. When i was pricing mine, aluminum was 30% more than steel with minimal weight savings. Current weight is 88 lbs (Frame weight: 46 lbs + metal grating: 42lbs).

 

[BlackWorksInc]

If you wanted to follow the curvature, a tube roller or tube bender could achieve it.

I measured distance between a level plane parallel to the highest point of the roof down to the roof itself in 6" increments to determine the curvature of the roof line front to back (Too bad i didn't do that from left to right.:ybrick and my fabricator just marked bend points and went to it.

Here are my old designs:

I agree with you, flat bottom racks look just as good so this might be a moot point.

If you can go with Aluminum, I say go for it. When i was pricing mine, aluminum was 30% more than steel with minimal weight savings. Current weight is 88 lbs (Frame weight: 46 lbs + metal grating: 42lbs).

Darkie! You've been holding out on me!!!

What are the measurements between the driver's and passenger side brackets and the driver's front to driver's rear bracket? Haven't you seen that I been asking for those measurements! LoL

 

[darkie3495]

Darkie! You've been holding out on me!!!

What are the measurements between the driver's and passenger side brackets and the driver's front to driver's rear bracket? Haven't you seen that I been asking for those measurements! LoL

haha...I haven't been holding out on you. The problem is that i took the measurements in 2009 and couldn't find the original files. just have these pictures on photobucket.

I am heading back to my parents house in the next few days and I can take measurements of my dad's roof rack (2006 4Runner)

And to be fair, you didn't ask me:bash::jk:

 

[jham]

I can't believe I missed this thread. I'm working on designing a rack for my 3rd gen, searched for others doing it as well.

I don't think I'll be doing full length. The one thing I haven't figured out is mounting points. Anyone know if simple L brackets work and hold weight well?

 

[darkie3495]

This is based on a quick measurement I took today:

The 55 3/4" measurement is a straight line from mount to mount and not taking into account that there is a slight angle caused by the different widths between the front and rear mounts.

Now you owe me a in-n-out double double animal style with fries!!!

 

[BlackWorksInc]

This is based on a quick measurement I took today:

The 55 3/4" measurement is a straight line from mount to mount and not taking into account that there is a slight angle caused by the different widths between the front and rear mounts.

Now you owe me a in-n-out double double animal style with fries!!!

I'll get you one if you come to the Hollister, CA Trail Ride this Sunday that Unionjack is organizing on the Toyota120 Forums.

 

[Djrashonal]

Here are my old designs:

WOW! I absolutely need this rack in my life. Where can I get one?

 

[darkie3495]

WOW! I absolutely need this rack in my life. Where can I get one?

Thanks....its being sold through Perkins Performance (Perkins Performance - Puyallup, WA)

 

[Djrashonal]

Thanks....its being sold through Perkins Performance (Perkins Performance - Puyallup, WA)

(Sorry for the ThreadJack)
Thanks! thats perfect, I'm flying up there on thursday!

 

[Casper421]

This is based on a quick measurement I took today:

The 55 3/4" measurement is a straight line from mount to mount and not taking into account that there is a slight angle caused by the different widths between the front and rear mounts.

Now you owe me a in-n-out double double animal style with fries!!!

Put me down for a 4x4 and cheese fries!! :hungry:

 

[darkie3495]

I don't think I'll be doing full length. The one thing I haven't figured out is mounting points. Anyone know if simple L brackets work and hold weight well?

L brackets should work as long as they are a thick enough gauge to handle the weight you put on your rack.

I'll get you one if you come to the Hollister, CA Trail Ride this Sunday that Unionjack is organizing on the Toyota120 Forums.

If i didn't have to drive 16 hours to attend, I would definitely be going.

Put me down for a 4x4 and cheese fries!! :hungry:

No fair, you already live in CA!! Can't wait until Friday....right after I land in LAX, i'm driving to the nearest In-n-out!!

 

[BlackWorksInc]

So I picked up some 6061 Aluminum Tubing OD 1.50" WT .125 (1/8") for a great price IMO. 80ft for $170ish with tax and all!

Unfortunetly trying to shoove a bundle of 20ft long aluminum tubing into a 4Runner is like trying to fit a giant into clown's car... I didn't notice that the loading guys and I had pushed the tubing too hard and cracked my windshield, lovely... Not to mention, the worst part is it nicked the dash cover and now there's this ugly little cut in my dash above the "Tune" knob!

Anyways, small rant aside. Was wondering, do any of you guys have any good resources on learning how to bend tubing and how to calculate stuff like that? I've never been a fan of math, but I understand this isn't something you can just wing very well.

 

[BlackWorksInc]

My head hurts... Trying to dimension my tubing to figure out length and bend angles, ect... the math is giving me a headache.

 

[Djrashonal]

any progress on it this weekend?