<o></o> <iframe title="YouTube video player" src="http://www.youtube.com/embed/vUMzncauZP0" allowfullscreen="" width="640" frameborder="0" height="390"></iframe> I decided to make a tech article on Tube Fabrication I get a lot of questions on tube fabrication such as where do you start your bend, how much do you bend it how do you cut a notch etc. <o></o> I hope you guys find this informative. Please forgive me for my poor acting skills. <o></o> Tube Bending: There is a couple different ways to do it, this is the easiest way for me is to make template bends. Remember how long the tube was before you started and where you start the bend then record how far your die traveled. You should be able to duplicate this bend over and over. No need to calculate spring back or how much the tube shrunk as you bent it, it is all taken out with the template. You can always put the tube back in and bend it more so slowly get your templates perfect. Always start the bend at the same reference mark on the bender I just use the back of the holding die easiest place for me to duplicate. Some people put a mark on the round die. <o></o> Record the distance the die traveled: <o>The degree ring on your bender is not the degree the tube bends but rather the distance the die traveled.</o> It doesn’t matter if you have a rotation die or a single shot bender you need to measure how far the die traveled it can be either angle or piston stroke inches. Just remember how far you went so can repeat the bend. <o></o> Just a friendly note. Plan out your bend order so you can actually bend them all. Nothing worse than when you start bending except the last one puts the tube into the ground. <o></o> <o></o> Second Bend Angle: When bending the second bend angles are hard to measure the angle so try to keep all the bends on the same plane if possible, you can usually get away by eye when it is on the same plane. You can also use an angle finder to do unique angles just remember the tube bends around the die so use the die angle as your reference frame, so add or subtract the die angle as required. They sell tube mounted angle finders our you can make your own clamp. Just a friendly note. Plan out your bend order so you can actually bend them all. Nothing worse than when you start bending except the last one puts the tube into the ground. <o></o> Example on how to use the templates and lay out your bends. I just used random numbers for this example. Make sure you have your templates facing the correct direction and mark which way you need to bend your tube. It really sucks when you bend it to the wrong side. <o></o> Splicing Tubes Together: Find a tube that will telescope inside your main tube or take the main tube slice a section out clamp it together and force it in a little harder but works. When you push the tube in put a tack to hold it in place so it will not slide when you insert the next tube this will keep the 2 tubes concentric and a nice solid base to weld to. It also adds a little extra strength at the joint if you want you can make the sleeve longer and plug weld it together. This can be used with complicated angles or replacing a tube. <o></o> Tube Notches/Fish Mouth: Tube notchers such as the Baileigh TN250 are great, you just need to know your angle and put on the correct hole saw. Without a notcher you just need to know what the notch needs to look like. You can make a template out by rolling a piece of paper around the tube and cut it out until it fits or use the pipe masters, and after a while you can just do it by eye. Once you know what the notch needs to be shaped as you can cut it with just about anything and finish it up with a grinder, file, or belt sander. I like the band saw for cutting the notch the way you can roll the tube on a band saw can get you very close to the tube notch profile. <o></o> Remember to grind back the notch to the thick metal you don't have any strength in the thin knife edge. I often use a 1/8” larger hole saw to give me a head start. Just the way I do it. <o></o> Example of what I’m talking about grinding the tube back. <o></o> Something I came across on the web that might help, Notch Profiles. Input your tube diameter and angle print it out trace it on your tube. http://www.metalgeek.com/static/cope.pcgi Bend-tech will also make tube notch templates. <o></o> <o></o> <o>A Welding tip: </o> Welding the top of the roll cage in a hard top, can get very tight, best way when starting off is to cut holes in the floor every spot the cage connects to the floor. You can slide plates under the cage, tack everything together, remove the plates drop the cage down weld it all together, lift it back up and slide the plates back under and then finish off welding the plates to the floor and to the cage. <o></o> I think I covered everything from the video. Hope you liked my Tech Article. Let me know if you have any questions. <o></o> Thank you Justin Williams customcreationsllc <o></o>
This man is the Professor of tube bending!!! By far the best tech I've seen all week, and very well edited. (not some boring long home movie).
Even more here: Bending 101 http://www.pirate4x4.com/tech/bendin_tube/index.html Chopsaw notching, tube strength and link construction http://pirate4x4.com/tech/billavista/Links/ Fastener tech http://pirate4x4.com/tech/billavista/NutsandBolts/index.html I know there are several crossover members besides myself and Baileigh, but for those who haven't looked check these out. Lots to be learned by venturing just outside the traditional realm.
Created this bend protracter years ago, gives me bend starts and ends also distance between bends. Use it inside door cars to measure cages. Allows me to size a rollbar for tight contour fitting in about 10-15 min. 1 5/8 tubing, 6" rad., marked every 10deg +45deg , will go 210deg
Thank you for the extra information, good to keep everything in the same place. I just finished reading through the articles. The Bending 101: Like I said there is other ways of doing it I just showed what works best for me. I just find the templates the most intuitive way. The templates method lets you figure out where to start all your bends at once and how much to bend it. It gets you really close to the length you need. You can start a book and record the bends starts and angles so you can always duplicate the same tube anytime you want. There is some good tech with the Pirate4x4.com their bending 101 method only estimate your overall length and you can only determine where to start each bend so you need to do 1 bend at time you cannot mark all the bends off on the tube at once. I bet compound angles would be hard that way too. Chop Saw Notching: I don't actually have a chop saw so never done it like that but like I say the notches are almost a straight cut I just like the band saw. I've probably made 1,000 notches on the band saw. Hole saw notchers are nice because it simplifies the equation you just set your angel and use the correct hole saw and you get a perfect notch. Chop Saw Initial cut angle chart could come in handy. Fastener tech: I didn't go into fasteners but thank you and there sure is a lot of good information on Pirate4x4.com ~Justin
Learn something new everyday. That is pretty cool I might have to copy that protractor, I can see it coming in real handy. You said you can can mark end bends and distance between bends? How do you know how much tube was used up in the bend? Or do you just mark off the second bend after your first bend? Thank you ~Justin
Thanks, and yes you can. I always start from the center of the roll cage and bend down (a mandrel bender only bends one direction and why its harder to use and measure layout). I mark the center of the roof and place the tool in the corner and adjust angle for conture. Measure from center to first mark on tool. That number is 1/2 the distance between the top bends. I mark the tool with a sharpie at the end of the bend (motion arm) and use another tool in possistion for the second bend lining up both legs of the tool again measuring the distance between finnish and start and marking the finnish point on the motion arm. Most cages take 11' tubing(tubing is cheap compared to my time so I figure long and cut off any extra so as not to spend time getting total lenth exact) which I mark the center, mark the first distance start and bend holding the tool over the tubing till the countour matches, with the tool mark the finnish and measure distance to the start of second bend, level tube and make second bend. Flip tube and repeat other side making sure tube is level. Heres a hint about using alignment sleaves when splicing tubing. split the sleave once lenthwise. tension will spring it open a little bit for a tighter fit and still be able to remove it during set up.
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