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Jonnie Fraz
12-25-2010, 10:36 AM
Ok boys and girls every so often I see guys with little to no experience in fabrication wanting to jump in and build a roll cage. Well here is a article I ran into to at least help with the bending part of it.
I did not write the article, all the credit goes to Rob Park on Pirate 4x4.

http://img.photobucket.com/albums/v635/Fraz-Man-One/Bending%20101/small1.jpg
Bendin' Tube 101
By Rob Park

I'm sure for some, when you first unpack your bender, you’ll be lost. I don’t blame you, it looks like some sort of medieval torture devise…

It’ll have some very confusing instructions and list of calculations that might as well be written in some ancient language. So you’ll throw some tube in the thing, pull the handle, and Ohhhh YEahhhh, you’ve bent tube with your bare hands! (In my best Tim Allen voice…aruh… aruhh... arhhh)

But now you’ve got a bent piece of tube, with no way to know where to start, or stop. I’d like to share some simple things I’ve learned, after what seems like miles of wasted tube.

Yes, there is another way to do it!

You don’t need some big computer program, a degree in math or even have to know more than just basic addition and subtraction. True, this is VERY BASIC, but with this, you can bend like a pro (almost)....lol

Here are some basic tools you should have…. A clean floor, level, measuring tape, permanent pen, adjustable square, protractor, framing square and my favorite home made tool that I like to call my “angle-o-meter”. lol
http://img.photobucket.com/albums/v635/Fraz-Man-One/Bending%20101/image002.jpg

A good stand is very important too. Try to get it level by measuring off the die.
http://img.photobucket.com/albums/v635/Fraz-Man-One/Bending%20101/image004.jpg
Again, this is by no means the only way, but in my opinion the EASIEST way to START. First step is to forget everything that you’ve heard or read about “centerline radius”, bend center, blah blah blahhhh…

Now throw a piece of tube in your bender and crank on the handle (get use to it, cause that handle is going to have to be pulled THOUSANDS of times to make your money back) and bend a 90. You can use your framing square as a guide by laying it on top of the tube while it’s still in the bender to make sure what you end up with is a 90.

Once you get that bent, take a look at how the tube “looks.” You’ll see that the inside of the bend has a small distortion where the bend starts, and where it stops. Sometimes, it’s just easier to “feel it”, by just running your finger around the inside of the bend. This “start and stop” is going to be the Guide that EVERTHING is based on. Once you have found this point, mark it with a pen.

* Remember, EVERYTHING from now on will be based on this mark *
http://img.photobucket.com/albums/v635/Fraz-Man-One/Bending%20101/image006.jpg


Now that that is out of the way, you have a place that you can measure from. Remember that big list of calculations that came with the bender? The one that somehow is supposed to tell you how to figure out how to measure and figure the bend. Pick up that list and toss it as far away from you as possible.

It’s as simple as this.
http://img.photobucket.com/albums/v635/Fraz-Man-One/Bending%20101/image008.jpg

Lay your 90 inside your square and see how many inches that it takes to complete the bend, start to stop. They both should be the same measurement, in this case it’s 5 ½”. See, by doing it this way, you’re not worried about what the centerline is or what size tube it is or any of that other “fancy” stuff. You KNOW that it takes 5 ½” to complete a bend.

Example: Say you want a hoop 60” wide to the out side of the bend… So it’s 60” – 11” = 49” from the start of bend…

Now keep that piece, because it’s now a VERY important tool. If you have more than 1 size die now is a good time to bend them to 90, measure and mark them too.

If you look at your die, you’ll see the point where your bend actually starts, (it’ll leave a mark, if not, you can use some grease) it should be about an inch or so from the leading edge. Since this is the point where it actually starts the bend, you’ll need to mark it on your die. This one is ground in, so you can see it, but a paint pen works too.

As long as it’s a bright color and you can see it, who cares.
http://img.photobucket.com/albums/v635/Fraz-Man-One/Bending%20101/image010.jpg

Once you have both your die and tube marked you’re all set! You now know where your bend will start, where it will stop, and have the ability to “rebend” exactly where you left off IF you come up short a few degrees on a bend.
http://img.photobucket.com/albums/v635/Fraz-Man-One/Bending%20101/image012.jpg

I guess the next step is trying to explain how to lay out what you want.

Lets take for example a simple B-pillar hoop (the one from side to side over your head). First, you need to find out just how wide, and tall you want it. This is where the “clean floor” comes in (from now on this will be your “layout table”). Draw a perfect square right on the floor with chalk the size of your highest and widest measurement. Next, draw yourself a centerline.
http://img.photobucket.com/albums/v635/Fraz-Man-One/Bending%20101/image014.jpg

Let’s just say the very top of your hoop needs to be 20” narrower than the sides, so measure in 10” from both top corners, and mark.
http://img.photobucket.com/albums/v635/Fraz-Man-One/Bending%20101/image016.jpg

Now let’s say that your door height or bed rail sits at 20”. So measure up from the bottom, and mark at 20”.
http://img.photobucket.com/albums/v635/Fraz-Man-One/Bending%20101/image018.jpg

Now we have every thing we need to finish the layout. Simply draw lines with a straight edge connecting the points to get your outline.
http://img.photobucket.com/albums/v635/Fraz-Man-One/Bending%20101/image020.jpg

Pretty fool proof so far?

Here is where that 90 you bent and marked comes in. Start from the center and work your way out and down. You simply lay your 90 on the floor parallel to your top chalk line, and slide it over till it intersects your down line, and mark the floor.
http://img.photobucket.com/albums/v635/Fraz-Man-One/Bending%20101/image022.jpg

Now do the same thing to your uprights.
http://img.photobucket.com/albums/v635/Fraz-Man-One/Bending%20101/image024.jpg

When you’re all done marking it, it should look something like this….
http://img.photobucket.com/albums/v635/Fraz-Man-One/Bending%20101/image026.jpg

Now lets get an idea of just how much tube it’s gonna take… Remember if you make it too long, it can always be cut down, BUT if it’s too short, you’re screwed. “LONGER is BETTER”… And after you get the hang of it, you’ll keep the waste down. Let’s add up the measurements.

20”+ 32”+ 20”+ 20”+ 32”+20” = 144”.

Now you can cut your tube, and just to be safe, give yourself a couple X-tra inches. Let’s just call it 148” total.
http://img.photobucket.com/albums/v635/Fraz-Man-One/Bending%20101/image028.jpg

*Work from the center out…

Once your tube is cut to length, mark the center, which ends up at 74”.

Next, simply line up your Tube on your layout , and mark where your first bend marks are, make sure to show the direction of your bend by marking an arrow on the tube. (Trust me, no matter how good you are you’re going to end up bending from the wrong side of the line sometimes, if you don’t) Remember... “from the center out” make both bends on “top” first, then the bends on the “uprights”.
http://img.photobucket.com/albums/v635/Fraz-Man-One/Bending%20101/image030.jpg

Chalk up your tube in the bender by lining up the marks and the direction arrow (seam to the inside).

Here is where the “angle-o-meter” comes in. Use it by finding your bend angle from your layout, then bend to the same angle by looking down it and comparing it to your bend.
http://img.photobucket.com/albums/v635/Fraz-Man-One/Bending%20101/image032.jpg

When you think you’ve got it, check it against your layout to make sure your “top” bend is still on track.
http://img.photobucket.com/albums/v635/Fraz-Man-One/Bending%20101/image034.jpg

Once that bend is complete, swap ends around and bend from the other mark, making sure your first bend is level. (2 man job)
http://img.photobucket.com/albums/v635/Fraz-Man-One/Bending%20101/image036.jpg

Now mark your next bends (the uprights) against your layout and bend them the same way. When you’re done with your bends every mark should line up like this.
http://img.photobucket.com/albums/v635/Fraz-Man-One/Bending%20101/image038.jpg

All that is left is to mark and cut it to the right height…
You can use the same technique to do door bars front hoops on and on and on….
I know this is only single plain bends and very simple, but it should help you to get STARTED.

* Here are few words of warning *

I wouldn’t suggest going in with someone to buy a Bender if you can help it… It WILL cause lots of problems and tension between friends.
You are taking your life into your hands by building a cage… Make sure you think LONG and HARD about that.
Take your time; build very simple stuff like bumpers, sliderz and such before ever attempting to build something that is meant to save your life.
IT’S NOT CHEAP. You’ll have to spend over 1k just for the bender and a couple dies, and that doesn’t include the welder, notcher, chop saw, grinders and all the countless other little nickel and dime stuff that it’ll take.
Rob Park
A.K.A. “Tin Bender”

Thanks guys Hope this helps out.
Jonnie

S14DB
12-25-2010, 10:49 AM
Bend-Tech Home (http://www.2020softwaresolutions.com/)

NNOCENT
12-25-2010, 10:54 AM
picture links need some TLC

Dustxking
12-25-2010, 10:54 AM
Good writeup idk if its my comp or something else but the pic's are not loading. Just x's

Jonnie Fraz
12-25-2010, 12:51 PM
I will check the pics...they are showing up for me no problem.

Bend Tech is some great stuff...I put this up here because some of these kids will spend less on their bender than I spend on one die for mine...much less a couple hundred on software.

eklips3
12-26-2010, 09:21 PM
Subscribed !!

240sxrb25
12-26-2010, 09:32 PM
yea i just weld pies together but thanks for the tremendously large and confusing talk about bending shit.

nieko
12-27-2010, 01:22 AM
^^^^ You sir are a complete fucking moron.

Thanks Jonnie.

atutt
12-27-2010, 01:53 AM
I will check the pics...they are showing up for me no problem.

Bend Tech is some great stuff...I put this up here because some of these kids will spend less on their bender than I spend on one die for mine...much less a couple hundred on software.

I know the pain.. When one die set costs me $600 (as I have customs and cross border shipping to deal with)

But these are also the same kids that will make their first fab project a 12 point roll cage and think they're master welders/fabricators. lol

Even though I use BT Pro I still have the P4x4 link bookmarked.

yea i just weld pies together but thanks for the tremendously large and confusing talk about bending shit.

Pipes eh???

Jonnie Fraz
12-27-2010, 06:45 AM
I know the pain.. When one die set costs me $600 (as I have customs and cross border shipping to deal with)

But these are also the same kids that will make their first fab project a 12 point roll cage and think they're master welders/fabricators. lol

Even though I use BT Pro I still have the P4x4 link bookmarked.



Pipes eh???

$600.00 is a bunch, but your bender is bad ass! Shipping on the dies is murder...I just got two more for Christmas.

yea i just weld pipes together but thanks for the tremendously large and confusing talk about bending shit.

Um..Pipe is for carrying water...DOM is for safety equipment.

PerilousActs
12-27-2010, 01:17 PM
Nice post.

I'm thinking of buying a JD bender and curious, as the article doesn't mention it. Doesn't the tubing tend to twist sometimes and get off plane? What are some ways to prevent this?

nieko
12-27-2010, 01:37 PM
http://img.photobucket.com/albums/v635/Fraz-Man-One/Bending%20101/image036.jpg

^^^

That would be this step.

As long as your bender is level, this should work pretty flawlessly.

PerilousActs
12-27-2010, 01:40 PM
Ah, thanks, man! I'm not sure how I missed that.

atutt
12-27-2010, 01:47 PM
$600.00 is a bunch, but your bender is bad ass! Shipping on the dies is murder...I just got two more for Christmas.



Um..Pipe is for carrying water...DOM is for safety equipment.

The dies themselves are only $300 - $400... But after said BS shipping, customs and taxes it's like a $600 die :(... And I currently have about 6 or 7 dies... Luckily, they came with my bender :D

http://img.photobucket.com/albums/v635/Fraz-Man-One/Bending%20101/image036.jpg

^^^

That would be this step.

As long as your bender is level, this should work pretty flawlessly.


There are more accurate ways of making sure they are on the same plane.
A POB attachment and a nice quality oil filled dial are the way to go in my books. Less crude than a half accurate level. I personally don't like the level...
The digital angle finders are pretty good too. Wixie makes some decent ones.

brainfood
12-27-2010, 01:51 PM
Thats a great article and that method is very easy. I learned a little differently but the principal is the same.

PerilousActs
12-27-2010, 01:53 PM
The dies themselves are only $300 - $400... But after said BS shipping, customs and taxes it's like a $600 die :(... And I currently have about 6 or 7 dies... Luckily, they came with my bender :D




There are more accurate ways of making sure they are on the same plane.
A POB attachment and a nice quality oil filled dial are the way to go in my books. Less crude than a half accurate level. I personally don't like the level...
The digital angle finders are pretty good too. Wixie makes some decent ones.
Yeah, the digital angle finders by Wixie are what I was actually looking at if I do get one. I'm just debating on whether to spend the money on the equipment now, or just pay someone to do what I want. -.-

atutt
12-27-2010, 02:05 PM
Yeah, the digital angle finders by Wixie are what I was actually looking at if I do get one. I'm just debating on whether to spend the money on the equipment now, or just pay someone to do what I want. -.-

It all depends on whether you're going to use it once. Or fully intend on using it again. Or furthering that by trying to make some money.

If you know you'll use it once. Just do some poor bastard a favour and pay him to do it. He's already poor enough by being in the auto fabrication field :p

More than once? Buy something like a JD model 3. Cheap, durable, and will do what you want/need

Make money? Something like a JD model 4 would be ideal. Because the JD4 can use dies from other companies. I can order die for my JD4 that will bend angle iron, square tube, rectangular tube, scroll work, flat bar (both length and width ways), etc...
If I were to make some mandrels for my machine I could bend up to 2.5'' IC and exhaust.
But at that point I may as well just modify the bender to accept something up to 4''...

brainfood
12-27-2010, 02:14 PM
The digital angle finder works great. I had an oil filled 360* angle finder but it got lost so I ordered the wixie because the cost was the same and it works great and is easy to use.