Homebrew Rooftop Cargo Basket

[FLYFISHEXPERT]

So I have some 1” diameter 1/32” wall 4130 chromoly tubing lying around in my garage, and I have decided to build a roof top basket for my 4Runner. The outside dimensions of the basket are 41”x59”x5”. I am thinking about using 1/8”x1” aluminum flat bar for the slats. What do you guys think? The open end will be to the rear of the vehicle, and I have offset the front bars to allow for a fairing. My plan is to bolt it directly to the roof rail tracks and not use cross bars.

Base Frame:
http://i197.photobucket.com/albums/aa211/beaukrista/4x4/roof%20basket/ROOFRACK.jpg

Frame with aluminum slats:
http://i197.photobucket.com/albums/aa211/beaukrista/4x4/roof%20basket/ROOFRACK2.jpg

[dustboy]

Somebody's been playing with SketchUp..

How will you attach the aluminum slats to the 4130?

Should be a light and strong rack.

[FLYFISHEXPERT]

Somebody's been playing with SketchUp..

How will you attach the aluminum slats to the 4130?

Should be a light and strong rack.

Well, actually SolidEdge. Software at work is great!

I was thinking about either riveting the aluminum on by drilling holes into the tube, or welding tabs off of the tubing.

[proto]

Nice work. (I especially like the shadow.) Hmmm. . . chromoly in that thickness. . . leftovers from a homebuilt aircraft project, perhaps? I like the concept, especially because it seems it'll be light weight.

(Sorry, now i'm going to ask a bunch of questions because there's a similar project in my future.)

It's a little tough to judge from the drawing, but what's the lateral span? (That is, across the top of the truck from left side to right side.) If it's 4 1/2 or 5 feet, do you think 1-inch tubing that long will be stiff enough? I guess that depends on what you're going to be toting up there.

Even as thin as your tubing is, can you get tight bends like that? Is there some technique other than a multi-thousand dollar mandrel bender?

I'm trying to imagine myself building something like this, looking at all the little braces that run fore and aft, and saying "that's a lot of tube ends to fishmouth"! Then weld. Then curse at because I put too much heat into the joint and warped everything. I'd probably just use long tubes in each direction and cross them.

Anyway, once you've welded it up, will you then heat treat it or normalize it, or whatever? Do you anticipate any 'difference of metals' problems attaching aluminum to the steel? How will it be fixed to your roof, gutter mounts?

OK, I'll stop now.

[FLYFISHEXPERT]

Luckily, I work in an industry with some very talented welders! I can't weld worth crap, but a buddy I work with in the R&D department is one of the best fab/welders I have worked with and he agreed to help me with the project. I own a tubing notcher, so that will help.

The material is leftover from a college human powered vehicle project. And I was wrong; it is .049" wall 4130.

Still not sure on the radius of the bends, I would like to have them mandrel bent, but we do not have the equipment at work, so it may not happen. I may be stuck with larger diameter.

I am only planning on using the basket to haul camping gear and gas cans. I hate the idea of placing heavy items that far up, but may make the rear strong enough to hold a spare tire. I have FEA on the computer to help with the strength questions.

The center to center distance between tracks is 37-1/2" and I think the material will by plenty strong to span that distance. I was thinking about using clamps like this to secure the basket to the factory rail tracks. McMaster-Carr is a wonderful thing.
http://www.mcmaster.com/catalog/115/gfx/large/3015t32p1l.gif

[hikingff77]

Well, actually SolidEdge. Software at work is great!

I was thinking about either riveting the aluminum on by drilling holes into the tube, or welding tabs off of the tubing.

I was going to say Solidworks.

Nice.

[NikonRon]

With 1" O.D. tubing I don't think you will be able to bend a very tight radius, I would suggest fabbing a 3 piece 90 degree turn since you will be making several welds anyway, just a few more to make. Ron

[KG6BWS]

if i remember correctly, the tightest radius you can bend in 1" is like 6 or 8". not positive on that though.

[FLYFISHEXPERT]

if i remember correctly, the tightest radius you can bend in 1" is like 6 or 8". not positive on that though.

You are right, I must have been thinking Min Bend for Sheet at the time I was drawing this up. I changed it to 4in. It will still be hard finding somebody to do this for me. I can get 6in using conduit benders at work. I am going to make some phone calls and see what I can come up with.

[KG6BWS]

you could still use a 8" radius bend. my light hoop on my roof was done with 1" EMT and a manual conduit bender. since it was way too big for what i wanted, i just bent it and then cut off the end to what i wanted. for your application, i think that would a perfectly adequate solution, especially for the ends. instead of having a perfectly square 90, you would have more of a 45, which IMO, would look better anyways.

http://i295.photobucket.com/albums/mm136/rigwelderstaco/100_0799.jpg

its kind of hard to see in this pic, but the hoop was made with 2 pieces, bent to 90 degrees, then cut off to give it the gap i wanted for the lights. if you look at the radius of the bend youll see what i mean. to me, that looks better. it kind of "flows" better, i guess you could say.

[FLYFISHEXPERT]

I like the light bar!!!
Changed the bend radius to 6in and made some additional changes:
http://i197.photobucket.com/albums/aa211/beaukrista/4x4/roof%20basket/ROOFRACK2-1.jpg

I may now set it up the other way so the open end is front. Not sure yet. If I do, I will make the closed end parallel.

[proto]

That's looking pretty nice! Have your welder throw in some gussets at all the little corners and you'll be good to go!

It would be interesting to see an FEA of your design. Just to get a feel for stiffness: how much would a 3-foot tube of this stuff deflect with a couple phone books on it?

[FLYFISHEXPERT]

That's looking pretty nice! Have your welder throw in some gussets at all the little corners and you'll be good to go!

It would be interesting to see an FEA of your design. Just to get a feel for stiffness: how much would a 3-foot tube of this stuff deflect with a couple phone books on it?

Using a simply supported beam calculation, a 30# weight placed in the center of the tube would deflect less than 1/16". Because this is not simply supported, it would be less.

[KG6BWS]

I like it!!!

Can't wait to see the finished product.

I don't think there would be any problems with the 1" tubing as long as they are complete. If youre going to strap anything up there from side to side and the whole tubes are going across (side to side) then I don't think you'd have any problems. Even if you were to put a tire up there I don't see it bending much, if at all. Mine is only sitting 1" sq. (running front to back) with Yakima crossbars at each end. Even bouncing it around offroad, its held up just fine.


Out of curiosity, did you use a drafting program for that?? I've never used any kind of CAD programs at all, and I would like to learn. I just don't really know where to start.

[corax]

Out of curiosity, did you use a drafting program for that?? I've never used any kind of CAD programs at all, and I would like to learn. I just don't really know where to start.


Try "Google SketchUp" - I have a phobia of CAD programs, but am trying to learn on this one and there are tons of tutorial videos out there. Usually all I end up with are a bunch of unconnected lines :D

[KG6BWS]

Try "Google SketchUp" - I have a phobia of CAD programs, but am trying to learn on this one and there are tons of tutorial videos out there. Usually all I end up with are a bunch of unconnected lines :D

heheh, yeah i dont even get that far. thanks though ill go check it out.

[FLYFISHEXPERT]

I used SolidEdge to draw it up. It is one of the two 3D CAD programs we have at work. I use it every day, I am a mechanical engineer, and it only took me 30min start to finish.

[KG6BWS]

I used SolidEdge to draw it up. It is one of the two 3D CAD programs we have at work. I use it every day, I am a mechanical engineer, and it only took me 30min start to finish.

i wish!! I either use MS Paint or a notebook.

[FLYFISHEXPERT]

Wow, spring was busy. Now I have time to finish everything up. Since I last posted regarding this project, I have made some additional design changes. I wish to incorporate 7" lights into the design, and have created a 'hoop' to protect them. Behind the hoop, I will place my existing fairing to help with aerodynamics. I am not so sure about the light 'hoop', it looked better in my head. Tell me what you think. The tall end is the front, and protects the lights. http://i197.photobucket.com/albums/aa211/beaukrista/4x4/roof%20basket/RoofRackwithLightHoop.jpg http://i197.photobucket.com/albums/aa211/beaukrista/4x4/roof%20basket/RoofRackwithLightHoopdrawing-1.jpg
Not sure if I want to go with the cheap HID lights from Checkers, or a pair of Hella 700FFs.
Here is what the HID's would look like. The HIDs are 8 1/4" in diameter and the Hellas are 7 1/4". (picture shows 4in and 7in HID lights)
http://i197.photobucket.com/albums/aa211/beaukrista/4x4/roof%20basket/DSCF6319.jpg

[buldyourown]

Maybe you are already aware of this, but you are going to have a hard time getting those bends with .032 wall tubing unless you have a mandrel bender.
Just my .02c


Design looks good. I've been toying with the idea of making my own. I've been going back and forth with the basket vs rocketbox.
Be sure to post some fab photos.

[FLYFISHEXPERT]

Maybe you are already aware of this, but you are going to have a hard time getting those bends with .032 wall tubing unless you have a mandrel bender.
Just my .02c

Yep, I can get a 6" bend radius using a hand conduit bender, but I am going to see if I can get them mandrel bent at CBI.

I love CAD! Added the lights!
http://i197.photobucket.com/albums/aa211/beaukrista/4x4/roof%20basket/RoofRackwithLightHoopandlights.jpg
The outside two are representative of the Hella 700FF, and the center one is representative of the HIDs from Checker Auto Parts. I am thinking about going with the Hellas.

[buldyourown]

Yep, I can get a 6" bend radius using a hand conduit bender, but I am going to see if I can get them mandrel bent at CBI.



It wasn't the radius I was concerned about. When the dia/wall thickness ratio gets too low, you get crimping no matter what. It may work with your bender, but in general, conduit benders are sized poorly for dimensional tubing.
What might work with soft conduit, will wrinkle 4130.
I would bet you will need to go at least .049 on the wall to get those bent without a mandrel. Maybe even .065
Let us know how it works out.

[washington taco]

You could try welding a end cap on the tube filling it with fine sand completely then welding a cap on the open end, then bend the tubing to the desired radius. I was tought this in aircraft mechanic school and it worked very good. The tubing was .032 5/8" CRES it may not work with 1". Obviuosly you would need to start with a longer piece of tubing then cut off the ends to dump the sand out.This should eliminate most of the kinks.

[proto]

Hey, Fly, good to see you're back on track with this project! I'd love to see how you make out getting this thing bent up and built.

I can tell you the Checker HID lights are really a step above Hella 700FFs (I have both). Some people seem think they're goofy-looking -- until you turn them on! :sombrero:

[FLYFISHEXPERT]

Thanks for the comments! I had an extra piece of tubing, I have most everything cut and notched, and bent it up using the conduit bender I mentioned above. It actually worked rather well. No kinking and only the slightest flat spot in the middle. Oh, I believe I corrected myself in a middle post, this is in fact.040" wall tube.

Oh and the cap and sand trick, we used that technique in college on a Human Powered Vehicle project, and it worked rather well.

About the lights...I was thinking about going with the Hellas, putting 100W bulbs in, and then after a while converting them to HID. I would save some money doing it this way... You know how budgets go.

It looks like it will be raining here again this weekend, I think SE Idaho planted itself on the coast, so I am going to try to get started this weekend. I have too many projects.

[dyogim]

About the lights...I was thinking about going with the Hellas, putting 100W bulbs in, and then after a while converting them to HID. I would save some money doing it this way... You know how budgets go.



Or you can just get a pair of these for $40: http://www.ddmtuning.com/index.php?p=product&id=102&parent=85

I ordered a pair and will install them in my Hella 700's. A member on TTORA has done this mod on a set of Hella 500's. I'm still waiting for night pics to see how bright these kits are but for $40, it's not a bad budget mod. Here's the link to the install:

http://www.ttora.com/forum/showthread.php?p=1664318#post1664318

[FLYFISHEXPERT]

Well after making some bends, yes we did get a couple to kink, but the two hoops are tacked together. More to come next weekend...

http://i197.photobucket.com/albums/aa211/beaukrista/4x4/roof%20basket/IMGP2740.jpg

[bobDog]

You can go to your local farm store and buy 2 chain link gates 4' X 6' cheap....the frames are 1" galvanized thick walled tubing w/ nicely rounded corners. Makes a nice frame to start with. :victory:

[JamesDowning]

Nice looking design! We use Catia here for all our CAD work.

Looking at your flooring slats in your above rendering, you may want to terminate the slats at a tube instead of in the air. It would be easy to get a soft bag or strap caught on a slat. It can be a pain in the arse to get up there and free stuff sometimes.

From an ME point of view, I like your thinking about doubling up the rods around the vertical bars. Are you planning to use the double rods as your attachment locations to your stock rack? Make sure the stock load bars can handle the weight, mine started bending on me so I ended up replacing them with square tubing.
http://images.thedownings.us/cheers.gif

[FLYFISHEXPERT]

Nice looking design! We use Catia here for all our CAD work.

Looking at your flooring slats in your above rendering, you may want to terminate the slats at a tube instead of in the air. It would be easy to get a soft bag or strap caught on a slat. It can be a pain in the arse to get up there and free stuff sometimes.

From an ME point of view, I like your thinking about doubling up the rods around the vertical bars. Are you planning to use the double rods as your attachment locations to your stock rack? Make sure the stock load bars can handle the weight, mine started bending on me so I ended up replacing them with square tubing.
http://images.thedownings.us/cheers.gif

I am still not sure what I will be doing for the 'flooring' we will see, I may just use expanded metal sheet.

I will actually be be attaching the basket directly to the T-slot rails that the factory load bars attach to. There will be some pieces of 1" square tube under each double tube cross tube. A bolt will go through a hole in the tube and bolt the basket in place.

[08whitex]

The full replacement Rack I built for my Xterra is made out of 1 inch emt conduit. The wall thickness is only .017 more. I ran 1 tube every 11 inches across a 3.5 foot width. I covered it with expanded metal. I have had over 500 pounds on my rack with about 1/8 inch of deflection.

I think your basket will be able to hold more then your roof will.

[FLYFISHEXPERT]

Well, after much delay...Summer is a busy time of year for me... I finally found time to finish the roof basket. Just in time for this coming week's big 1400 mile road trip.

I owe a big thanks to my friend Carlos who welded everything up for me as I fabed parts. Definitely helps when you can find someone who knows what they are doing.

The basket sits about 1" to 3/4" off of the roof and is 6" tall at the back and raises 9-1/2" up at the front to protect my IPF lights. It is 42" wide outside to outside and 60" long. This thing is huge!!!

Here is how I made the attachment points to the factory rails.
http://i197.photobucket.com/albums/aa211/beaukrista/4x4/roof%20basket/DSCF6623.jpg

Here it is prior to painting. I am using my old Thule fairing.
http://i197.photobucket.com/albums/aa211/beaukrista/4x4/roof%20basket/DSCF6620.jpg

And here it is all painted up.
http://i197.photobucket.com/albums/aa211/beaukrista/4x4/roof%20basket/DSCF6624.jpg

Now I just need to wire up the lights and make some mounts for the Hi-Lift out of some 1" lock collars and bolts. I am planning on mounting it to the inside bottom of the basket to keep it out of the way.

[4307]

Looks really good :sombrero:. What kind of paint did you use?

[FLYFISHEXPERT]

Looks really good :sombrero:. What kind of paint did you use?

Rustoleum satin black. Cheap WalMart paint.

When I return next week from my trip, I will probably add two coats of herculiner to the tops of the cross tubes to protect them from chips and help keep stuff stationary.

[dyogim]

Rustoleum satin black. Cheap WalMart paint.

When I return next week from my trip, I will probably add two coats of herculiner to the tops of the cross tubes to protect them from chips and help keep stuff stationary.

I'd suggest adding some strips of grip tape (roll of sand paper tape) on the bars if you plan on standing on top.

Great job BTW!!!

[luckyrxc]

you could still use a 8" radius bend. my light hoop on my roof was done with 1" EMT and a manual conduit bender. since it was way too big for what i wanted, i just bent it and then cut off the end to what i wanted. for your application, i think that would a perfectly adequate solution, especially for the ends. instead of having a perfectly square 90, you would have more of a 45, which IMO, would look better anyways.

http://i295.photobucket.com/albums/mm136/rigwelderstaco/100_0799.jpg

its kind of hard to see in this pic, but the hoop was made with 2 pieces, bent to 90 degrees, then cut off to give it the gap i wanted for the lights. if you look at the radius of the bend youll see what i mean. to me, that looks better. it kind of "flows" better, i guess you could say.


My goodness, that's a strong dog to pull that truck.

[4RNR]

I to have decided to make my own roofrack and am curious as to how you mounted yours. I have a 1990 4Runner that did not have a factory roof rack and dont want to mess the roof up on the first try. Any suggestions or pictures of the mounting process you used. Thanks in advance.

[Willman]

Love the rack!

I have had rack fever for a while now.....

Might be time to bust the tools out again....

;)

[FLYFISHEXPERT]

I to have decided to make my own roofrack and am curious as to how you mounted yours. I have a 1990 4Runner that did not have a factory roof rack and dont want to mess the roof up on the first try. Any suggestions or pictures of the mounting process you used. Thanks in advance.

I made 4 feet that came down from the double cross tubes and used some flat bar to secure it to the rails.
http://i197.photobucket.com/albums/aa211/beaukrista/4x4/roof%20basket/DSCF6623.jpg

Here it it at our first camping spot on this past week's 1600 mile road trip.
http://photos-e.ak.fbcdn.net/hphotos-ak-snc1/hs257.snc1/10427_1052909781365_1784404091_106652_3059046_n.jp g

The big plastic containers go inside when we are driving.

I did notice that with the weight of the NATO fuel can right over one of the feet made the roof pop when driving over rough roads. I am going to have to find a better location for the fuel can. Has anybody else encountered this problem? I just don't think the roof/roof rails can handle the load of fuel cans on the roof. Blast. Well at least I can get some of the lighter/more bulky items out of the vehicle and on top. It worked great for storing camp chairs and firewood.