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  #1  
Old 10-14-2015, 09:37 AM
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Looking for tubing recommendations

Looking for some recommendations for tubing for a removable roof rack that I am looking to design and have built.

The rack would be mainly to haul a canoe or small boat, but sometimes camping gear – let’s say 200# max .

First question, what type of tube – DOM, Welded Seam, Structural Steel? Is there something else out there that is more economical?

Second question, what size?
What size tubing for the rack itself and, since I want it to be removable, what size tubing to use for bracketry that the rack will slide into- basically sleeving the two?

I already have a design in my head. And once I know what size materials I am going to use, I can draw it up in CAD for the fabricator.

As always, thanks in advance….!

2X
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Old 10-14-2015, 12:34 PM
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The appropriate size tube will depend on the overall design of the rack, for example where and how crossbars are attached, if there are ladder elements or just single bars, or what. On the extreme ends, you could have wire basket that uses lots of tiny 1/8" or so wire or you could have two 1-1/2 x .120 wall HREW tubes running along side eachother and attached to the roof at each end.

Can you post a sketch of your design?
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Old 10-14-2015, 01:54 PM
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Bandit is right.
The minimum information would be:
Hows it mount?
Size?
Function, What will it carry?
And I would say, will it be hit by anything like tree branches and such?

E
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Old 10-14-2015, 02:12 PM
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I am planning for the front 'hoop' to slide into brackets consisting of larger tubes attached to windshield hinges (CJ-7) and the rear 'hoop' to mount in the same manner in brackets attached to rear bumper.

3-4 bars running front to back. which works out to roughly 6.5 feet.

For carrying canoe and possibly camping gear - 200# max.

Ideally it would not hit branches, although brushing along some smaller foliage may be inevitable. Definitely won't be taking any 'blows'.

I can't figure out how to post a pic, but her is a link to something similar, minus the 'humps':
http://www.safarijeeps.com/jeep-cong...to-1995-black/
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Old 10-14-2015, 02:21 PM
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Well they used 1 5/8" on that rack and I would say that would be a good size overall at-least for that framework.
The remainder could be 7/8 to 1".
Material wise HREW mild steel is going to be just fine.

Just my opinion though!!

E
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Old 10-14-2015, 02:36 PM
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Quote:
Originally Posted by entropy View Post
Well they used 1 5/8" on that rack and I would say that would be a good size overall at-least for that framework.
The remainder could be 7/8 to 1".
Material wise HREW mild steel is going to be just fine.

Just my opinion though!!

E
Everyone here values your opinion, E!

What is HREW?
I'll have to find 2 sizes that slip together, with 1-5/8 being the minimum.
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Old 10-14-2015, 03:17 PM
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Originally Posted by 2Xtreme View Post
Everyone here values your opinion, E!

What is HREW?
I'll have to find 2 sizes that slip together, with 1-5/8 being the minimum.

HREW

Also called ERW.
You can see the weld as a line down the length of the tube.
Suitable for about 90% of anything built out of tube except Race-cars and Airplanes.
Nearly always Mild Steel.

To save your the time of getting the internal weld flash out of the ERW, you can put a short section of DOM where the rack will slid in. DOM is generally available by the foot...

E
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Old 10-16-2015, 09:59 AM
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Thanks for the link...

So I think I am going to go with:

1-5/8"OD HREW, .065" wall for the rack and
1-7/8" OD, .065" DOM for where the rack will slide in.

Sound good?
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Old 10-16-2015, 12:21 PM
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For what you are building sounds gooot!
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Old 10-16-2015, 02:09 PM
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So far....

Although now that I am looking at it, it may be better to go all the way forward with similar brackets on the front bumper... But then again, that would require materials

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Old 10-16-2015, 02:18 PM
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Why all the sleeves?
I can see the need to pivot one end may-be. . . but??
IF it is to allow Install/removal you're likely to hate getting all of that lined up and sliding at the same time.

E
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Old 10-16-2015, 02:26 PM
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I guess you are right. The front doesn't need to pivot.

Guess I just got carried away. Before I started drawing it out, I wasn't intending to pivot the front, for just that reason.....
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Old 10-16-2015, 02:39 PM
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Make the rear mounts bolt on and eliminate that slip joint there completely and if you did that you can fully weld the entire cage with just the slips at the bottom of the front tubes being necessary.

The other thing here is this is going to take 3 people to install or remove and once the thrill wears off it will just stay on all the time at which point. . .
Just make it bolt on all the way and save the slips for something else.

Always Strive for a KISS

E

PS. Looks clean.
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Old 10-16-2015, 02:49 PM
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Quote:
Originally Posted by entropy View Post
Make the rear mounts bolt on and eliminate that slip joint there completely and if you did that you can fully weld the entire cage with just the slips at the bottom of the front tubes being necessary.

The other thing here is this is going to take 3 people to install or remove and once the thrill wears off it will just stay on all the time at which point. . .
Just make it bolt on all the way and save the slips for something else.

Always Strive for a KISS

E

PS. Looks clean.
The problem if it is fully welded is storage when it is not on the Jeep.
Yes, it may end up staying on most of the time. But if it's not, I don't really have anywhere to store it if I can't collapse it.

Thanks!
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Old 10-16-2015, 05:26 PM
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Where are you located. If on one of the coasts you might look into Aluminum. There are many boat "Tuna Tower" fabricators out there that can make a simple rack like you are thinking about that will be much lighter and easier to remove. 200# of weight is not that much. You will probably end up with more drag force than that as you go down the road.

So even a lighter weight steel tubing should work. You could look into 1 1/4" EMT. Which is basically galvanized electrical conduit. The galvanizing can be ground off welded and the hit with cold galvanized coating.


Carl
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Old 10-17-2015, 09:41 AM
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Quote:
Originally Posted by cbrogers View Post
Where are you located. If on one of the coasts you might look into Aluminum. There are many boat "Tuna Tower" fabricators out there that can make a simple rack like you are thinking about that will be much lighter and easier to remove. 200# of weight is not that much. You will probably end up with more drag force than that as you go down the road.

So even a lighter weight steel tubing should work. You could look into 1 1/4" EMT. Which is basically galvanized electrical conduit. The galvanizing can be ground off welded and the hit with cold galvanized coating.


Carl
I'm in upstate NY, about 3 hrs from the coast.
But I will look into the Aluminum option.
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Old 10-19-2015, 04:13 PM
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Depending on where upstate you might find a boat builder close. The tubing for bending and putting up Tuna Towers are the same as the boat guys who do Ski boats and towers or pull points for them. You also might find someone who does aircraft stuff. Especially the experimental crowd. They work with lighter weight tubing and might help.

If you are near Elmira there is a Glider Manufacturer that might be able to point you in the right direction.


Carl
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Old 11-19-2015, 11:26 AM
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I don't mean to ask an insulting question, but I have seen plenty of these sold as bolt-on kits. Any reason you're making one?
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Old 12-01-2015, 03:59 PM
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I don't mean to ask an insulting question, but I have seen plenty of these sold as bolt-on kits. Any reason you're making one?
Aftermarket support for CJ's is dwindling.

When I was looking, I think I only found 2 bolt on racks to suit my needs and one, the Kongo Cage (or something) has huge 'humps' in the side tubes to clear the roll boar.

It looks terrible. Not that mine is a work of art.....
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Old 12-01-2015, 04:38 PM
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Aftermarket support for CJ's is dwindling.
Man times have changed! When I was a kid in the 80s and early 90s my mom had a CJ5 and I remember phone-book sized catalogs of just about any accessory you could imagine, complete with option of chrome or stainless. I bought her a few for birthday presents - the most random stuff like chrome wiper motor covers and glove box doors. You had your choice of however many shocks you could afford for suspension or steering, soft tops in canvas, burlap, or woven hemp, and chrome chain steering wheels. Man I miss the good ol' days... does JC Whitney still exist?
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