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kanoa9321
06-22-2006, 02:13 AM
I need some advice on how to calculate a bend. Im building a roll cage and need to bend the tube that goes from the foot area straight up then along the A pillar and then along the roof on top of the door. If you are looking at the vehicle from the side I know how to do the standard 2 bends. But if your look from the top down the tube goes along the roof and then bends down and at the same time bends a little toward the interior. I understand the first bend doesnt matter but for the second bend they arent in the exact same plane, when placed in the bender it needs to be angled down a bit but how do I calculate this when its in the bender? I can measure it on the car but how do I transfer it to the tube to bend.

I know you are probably completely lost right now but I have a picture to help. It shows what I am trying to do, you can see how the two bends aren't directly in a straight line.
http://www.rally18.com/racing/Jet11.jpg

hope you can understand what I am trying to say.
Thanks

Diverbill45
06-22-2006, 02:48 AM
The best thing I can tell you right now is, lay everything out on the floor.

Take some measurements and then get some soapstone, a 2 foot square and some sort of straight edge and transfer the measurements you have to the concrete floor.

After you have everything laid out, on the floor, you will find out that will be alot easier to work with.

What type of bender are you using to bend your tube?

Right now I'm at my sons house in southern California, so I really can't help you much, but as soon as I get home next week, I'll have all my information in front of me so I can give you some more info on the subject.

Hope this is of some help.

lotechman
06-22-2006, 08:54 AM
I use a protractor and bubble level to level or tilt legs when bending out of plane. Better yet is a quality digital level. You need two people, one to hold and locate the bend at the dies and the other to rotate and hold the leg at the correct slant.

kanoa9321
06-22-2006, 05:57 PM
I know about laying it out on the floor but the second bend is not in the same plane so that wont really help on how much to rotate the tube for the second bendomg

lotechman you just gave me a brilliant idea I just bought a new digital camber gauge that you can zero to anything and has a million functions, can practically set up your camber if your cars upside down. This will work perfet

thanks soooooooo much :cool2:

lotechman
06-22-2006, 10:07 PM
This will work perfet

thanks soooooooo much :cool2:

Just make sure that your bender is level or vertical according to the type. If it is not and you assume it is then your relative angles will be incorrect. Gee... I can't remember exactly how I know this.

Captainfab
06-22-2006, 10:22 PM
I've done quite a bit of tube bending. I used to do it the hard way...laying it out on the floor or cardboard,using sample bends to determine starting points.Then I bought a digital protractor,which made life easier for determining angles. I also used to tack a piece of 1/4 x 3 x 6 on the tube to mount the digital protractor or a torpedo level.

Then a couple of months ago I bought Bend-Tech Pro from 2020 Software Solutions.http://www.2020ssi.com It was a little spendy at \$275 but once you use it you realize that it's well worth the \$ (they also have less \$ programs). I also began making and selling plane of bend brackets. They clamp on the tube and give you a place to attach a magnetic protractor.

You can get some really good ideas on a site I frequent http://www.offroadfabnet.com lots of friendly and helpful people there. I would try and explain to you how to do what you are trying to accomplish but I tend to be long winded. Check out OFN and if you still have any questions I'll be glad to try and help.:)

Also buying tube bending software also depends on how much you plan to use your bender.

anthofab
06-24-2006, 04:32 PM
Here's a good article I've used, give it a read though and see what you think. It's probably not exactly what you're looking for but others might find it helpful.
http://www.pirate4x4.com/tech/bendin_tube/index.html

kanoa9321
06-25-2006, 12:15 AM
I read that awhile ago, but it doesnt mention bends in different planes. But like you said its a really good article simple and to the point.

I think I got it figured out how I will go about doing it just need some more tube.

TEK
06-25-2006, 01:33 AM
Here's a good article I've used, give it a read though and see what you think. It's probably not exactly what you're looking for but others might find it helpful.
http://www.pirate4x4.com/tech/bendin_tube/index.html

Hey, good first post!!! Welcome to the club!!:cool2:

Captainfab
06-26-2006, 12:53 AM
That arcticle on Pirate is a good one with useful info. pretty much how'd you do it without software of some kind. Basically when you have a bend in a different plane you need to attach something to the tube to which you can set a degree indicator on so you can keep track of how many degrees of rotation you turn the tube between bends. Of course you first have to figure out what the degree of rotation needs to be. Sometimes there is a bit of trial and error involved.:)

stomper4x4
06-26-2006, 08:50 PM
http://www.pirate4x4.com/tech/bendin_tube/index.html

I like and use this http://www.2020ssi.com/

kanoa9321
07-08-2006, 01:33 AM
Just wanted to say thanks guys. Between the pirate 4x4 tutorial and your advice I got the main hoop and the two door posts all bent and they came out exactly how I wanted.

Thanks guys :drinkup:

stomper4x4
07-08-2006, 08:30 AM
good job, no matter what method you use to figure out bend locations and angles, it all boils down to how well you set the tube up in the bender; Making shure you hit all your marks evry time...

kanoa9321
07-08-2006, 05:09 PM
yup ! its just a matter of figuring how you are going to go about it. Doesnt take a rocket scientist or calculus formulas just simple math and knowing where to start.

Wannabe
09-17-2006, 02:23 AM
Here is another good link over on Pirate 4x4 explaining how to notch tube using a chop saw.

09-19-2006, 07:03 PM
I've done quite a bit of tube bending. I used to do it the hard way...laying it out on the floor or cardboard,using sample bends to determine starting points.Then I bought a digital protractor,which made life easier for determining angles. I also used to tack a piece of 1/4 x 3 x 6 on the tube to mount the digital protractor or a torpedo level.

Then a couple of months ago I bought Bend-Tech Pro from 2020 Software Solutions.http://www.2020ssi.com It was a little spendy at \$275 but once you use it you realize that it's well worth the \$ (they also have less \$ programs). I also began making and selling plane of bend brackets. They clamp on the tube and give you a place to attach a magnetic protractor.

You can get some really good ideas on a site I frequent http://www.offroadfabnet.com lots of friendly and helpful people there. I would try and explain to you how to do what you are trying to accomplish but I tend to be long winded. Check out OFN and if you still have any questions I'll be glad to try and help.:)

Also buying tube bending software also depends on how much you plan to use your bender.

The Bend Tech program is GREAT. The support they give (or Chris gives) is great also. Its worth checking out

stomper4x4
09-19-2006, 10:24 PM
I use bend tech pro, great product, and like stated earlyer Chris is a great guy who will do what ever he can to help you with whatever you may need...