heavy85 Posted October 8, 2009 Share Posted October 8, 2009 I found a local shop that will order the metal and bend the tube for me. It'll be a basic 4-point bar with diagonal and cross brace. I already have the harness bar welded between the towers. Given Murphy's law etc how much tubing should I have them order as I dont want to be short? It looks like the main hoop takes a minimum 10' length and the rest are shorter but I dont know how he orders the metal. I tried to order myself but they wont deliver over 8' to a non-business address. I'm thinking maybe 40'? When I asked how much to bend it he said $5 a bend. It was an older guy that said he used to build cages but does not much anymore because he doesn't have the time and comes highly recommended. I think I'll negotiate and see if he'll take $10 a bend depending on what he charges for the steel and how much time it actually takes him! Cameron Quote Link to comment Share on other sites More sharing options...
74_5.0L_Z Posted October 8, 2009 Share Posted October 8, 2009 Here are the dimensions that I used to construct my main hoop. I believe that the leg length dimensions are a little long (so you will need to trim to fit). A few members have already built roll bars based on these dimensions. I have gotten feedback that the fit was good. http://album.hybridz.org/showphoto.php?photo=2004&ppuser=7833 Quote Link to comment Share on other sites More sharing options...
neotech84 Posted October 8, 2009 Share Posted October 8, 2009 When I asked how much to bend it he said $5 a bend. It was an older guy that said he used to build cages but does not much anymore because he doesn't have the time and comes highly recommended. I think I'll negotiate and see if he'll take $10 a bend depending on what he charges for the steel and how much time it actually takes him! Cameron Wait you want to pay more??? Quote Link to comment Share on other sites More sharing options...
heavy85 Posted October 8, 2009 Author Share Posted October 8, 2009 Here are the dimensions that I used to construct my main hoop. I believe that the leg length dimensions are a little long (so you will need to trim to fit). A few members have already built roll bars based on these dimensions. I have gotten feedback that the fit was good. http://album.hybridz.org/showphoto.php?photo=2004&ppuser=7833 Thanks for that. I was already planning on using your print which is where I figured the ~10' requirement for the main hoop. Now with screw-ups, nice to have, etc how any recommendation how more tubing should I order? Cameron Quote Link to comment Share on other sites More sharing options...
heavy85 Posted October 8, 2009 Author Share Posted October 8, 2009 Wait you want to pay more??? I figure most shops are ~$50 an hour to cover overhead and still make somewhat of a living. So 4 bends @ $5 a bend = $20 or about 24 minutes of work. I'm guessing he will spend more time with me than that and really wont make a penny on the whole thing. I would rather take care of someone local that's good and I can go to rather than trying eek out every penny from him. I'll see if he charges extra for the tubing, etc and then we'll work out how much he's worth but if he orders tubing for me (again I dont have anywhere it can be delivered since I dont have a loading dock), cut's a bar to length and adds 4 bends, and only charges $20 then I'll give him more to really cover his time and I'll still be way ahead. Cameron Quote Link to comment Share on other sites More sharing options...
JMortensen Posted October 8, 2009 Share Posted October 8, 2009 If it helps it's been a couple years but I believe I paid about $350 to a roll cage designer/builder here locally for bending the hoop and supplying enough tubing to do the full roll bar with diagonal and shoulder bar. Quote Link to comment Share on other sites More sharing options...
johnc Posted October 8, 2009 Share Posted October 8, 2009 You should buy two sticks of tubing (each "stick" is 18 to 22 feet long). That's the cheapest per foot rate. Extra tubing will come in handy for future projects. Pay the bender guy for one hour of his time at his normal rate. You'll get a main hoop that's bent well and all in the same plane. If a shop is busy its not worth their time to stop what they are doing and setup for four bends to get paid for 24 minutes of work. Most likely they will ask you to go somewhere else. And that whopping profit from being paid for one's hour's work and only spending 24 minutes on it doesn't go far toward's the shop owners retirement. We are not getting rich doing this. Quote Link to comment Share on other sites More sharing options...
heavy85 Posted October 8, 2009 Author Share Posted October 8, 2009 You should buy two sticks of tubing (each "stick" is 18 to 22 feet long). That's the cheapest per foot rate. Extra tubing will come in handy for future projects. Pay the bender guy for one hour of his time at his normal rate. You'll get a main hoop that's bent well and all in the same plane. If a shop is busy its not worth their time to stop what they are doing and setup for four bends to get paid for 24 minutes of work. Most likely they will ask you to go somewhere else. And that whopping profit from being paid for one's hour's work and only spending 24 minutes on it doesn't go far toward's the shop owners retirement. We are not getting rich doing this. Thanks John I'll do that. Your comments are exactly why I said I would pay more than he is asking. I'm willing to pay fairly for his time since he comes with high recommendations and I know he's busy. From my perspective he's doing me a favor. JM - $350 put's it into perspective. Looks like the metal is $2-300 for 1 3/4x0.95 DOM so with labor that's about right. Cameron Quote Link to comment Share on other sites More sharing options...
74_5.0L_Z Posted October 8, 2009 Share Posted October 8, 2009 Cameron, The dimensions on my roll bar gives a VERY tight fit. If the guy bending your bar makes an error tell him to make it on the narrow side. If the bar is any wider than my dimensions, it will not fit. Here is the fit in my car: Quote Link to comment Share on other sites More sharing options...
johnc Posted October 9, 2009 Share Posted October 9, 2009 If the bar is any wider than my dimensions, it will not fit. There's an old racer trick for when the rules don't allow any additional mounting points. Make the main hoop a bit wide for the car and then weld two loops at the bottom on the inside of each leg. Put a come-a-long between the legs hooked to the loops and pull the legs in enough to slide the bar in place. Remove the come-a-long and let the bar press hard against the sides of the car. Make sure the plates are all in place and everything's ready to weld. 1 Quote Link to comment Share on other sites More sharing options...
JMortensen Posted October 9, 2009 Share Posted October 9, 2009 I was right in the middle here. My bar was tight (sprung against the sides) when the bottoms of the hoop were slipped inside the rockers. When I cut the tubes vertically in half, then the bar was probably 3/4" loose between the rockers. I welded the plates to bar, then set it in place and used a portapowr to spread the hoop and welded the plates to the rockers. I had to beat in the little protruding areas where the clips go for the interior panels right behind the door opening. I used Dan's gif but with a different size tube and the guy who bent it did all the recalculating of angles and all that to make it come out right. Quote Link to comment Share on other sites More sharing options...
heavy85 Posted October 13, 2009 Author Share Posted October 13, 2009 Would anyone have the CAD ability to take 74_5.0L_Z's drawing and convert to 1 3/4 tubing? I'm wondering if the shop can readily recalculate the angles because it would take some time for me to do it and he doesn't even have e-mail so I'm not thinking he will plug into a tube bending program and convert it. I'm heading there on Wednesday to give him the print. Thanks Cameron Quote Link to comment Share on other sites More sharing options...
johnc Posted October 13, 2009 Share Posted October 13, 2009 He should be able to work it out just fine. If anything he can draw the outline on a work table and then bend to that drawing. Quote Link to comment Share on other sites More sharing options...
JustinOlson Posted October 20, 2009 Share Posted October 20, 2009 Depends on the center line radius of the die set he is using. It is unclear from 74_5.0L_Z's drawing as two what the centerline radius is. It looks like he is calling out a 7.0" inside radius, which would turn into a 7.8125" centerline radius on 1.625" material. That doesn't add up with the rest of the dimensions provided. When I draft it up using the other dimensions for the relations, it figures out to 7.0" CLR. Anyways, you shoudl be able to take the given dimensions and use them for 1.75" material without changing anything since it is given in exterior dimensions that make tube diameter irrelevant. The 1.75" tubing will just intrude into the passenger compartment more then the 1.625" tubing. J Quote Link to comment Share on other sites More sharing options...
74_5.0L_Z Posted October 22, 2009 Share Posted October 22, 2009 I had my roll bar bent by the guys at ChassisShop where I bought the tubing. They bent it using a die with a 7.0" centerline radius. I asked them about their bending equipment before I generated the drawing. The as received bar was an almost exact match to the drawing. They charged me $80.00 to do the bending, but the quality of the work was worth it. Quote Link to comment Share on other sites More sharing options...
heavy85 Posted October 23, 2009 Author Share Posted October 23, 2009 I dropped your print off and he said it wasn't a problem. He starts from the middle and bends out to each side using the centerline dimensions and would adjust for the different tube diameter. He was able to order 40' (two 'sticks') of 1 3/4 x 0.095" DOM for $200 delivered to his door and I'm paying his cost. From internet searching this seems to be about as low as I could find without delivery so it's better than I could get by far. I dont have an exact date but expect to hear from him in the next week. It's an old shop full of well used equipment and the owner who is probably 65+ was hanging out with two other gray hears shooting the breeze when I got there. I would swear it's more of a hobby shop that used to be a business and he's more or less retired but he's still got signs out front and is in the phone book. Cameron Quote Link to comment Share on other sites More sharing options...
heavy85 Posted November 13, 2009 Author Share Posted November 13, 2009 I got the bar back. It's TIGHT. Here is it wedged in the car. I'm debating on where to locate it and looking for feedback. It is literally wedged in the there touching the wheel wheel down low, the side just behind the nubbin right below the front edged of the 1/4 window and touching the roof. You couldn't get a tighter fit with as many contact points. The only trade-off here is it's hitting the roof structure about 3/4" below the skin of the roof. 74_5.0L_Z put his in front of that previously mentioned nubbin which pulls it forward where it's in front of the roof structure and also away from the wheel well. This gets that extra 3/4" height but also compromises contact points and the ability to tie it in all around. Thoughts? Next question has to do with the bends themselves. I've never bent rollbar tubing and the tube bender used was a high $$ hydraulic production type of bender. He also used to build cages often as a living and his personal dragster was top notch. However the bends are perfectly round. You can feel the tube get a little oval in the bends and the transition from bend to straight there is a slight wave to it in a couple places. Is this normal or do I need to find another shop (or cave and buy one) to rebend this thing? You can kind of see it here but it's hard to see. Thanks Cameron Quote Link to comment Share on other sites More sharing options...
JMortensen Posted November 13, 2009 Share Posted November 13, 2009 What you have there looks good to me and it sounds like you got a great deal. I don't think the bends are a problem. Unless you have a mandrel bender there is going to be some stretching of the tube. I'd try to get the bottom as close to the wheel well with the top as close to the map bar as you can. I think you've already seen that it's a compromise one way or the other. Then you get to figure out how you want to mount the bottom of the hoop to the car and decide where you're going to cut the tube. That was the nerve wracking part for me. Since mine was sprung against the rockers I notched the tube and attached it right to the rockers. What I would do in retrospect is build out the rockers in that area so that the tube sits right on top of the rocker which is maybe 2" wide or something like that. It's tough to get around the backside of the hoop, I cut holes in the fenders, both in the wells and in the dog legs to get access. Id suggest you tie into as many surfaces as you can, the walls of the car, the rockers, wheel wells, the floor, etc. Quote Link to comment Share on other sites More sharing options...
johnc Posted November 13, 2009 Share Posted November 13, 2009 Good fit. Some suggestions: Depending on how tall you are, you might want to stand the bar up a little bit to get it just in front of the hinge support roof structure. You want the main hoop within 6" of your head as you sit in the race seat. Weld 4" wide tabs from the hinge support structure to the main hoop in two place near where the rear braces meet the main hoop. Cover over the opening in top of the rear strut towers with plate and run the rear braces just outside of the mounting point for the struts. Add a horizontal brace from the main hoop at shoulder height to the rear brace. Quote Link to comment Share on other sites More sharing options...
74_5.0L_Z Posted November 14, 2009 Share Posted November 14, 2009 Looks good. When I installed mine I lined it up so that the roll bar was parallel to the line of the quarter window. To do that, I had to remove the "little nubbin" that you referred to below the quarter window. To remove it, I just used a hole saw. Because it is a tight fit, you will have to strategically plan your welds. If you are not careful, you will end up with welds that you can't reach. I planned mine so that the main hoop, diagonal, downtubes, strut support, and the tubes that go from the sides of the main hoop to the strut brace could be completely removed from the car for final welding. The following picture shows all of the rear structure installed in the car but not welded to the car. Basically everything in this picture was completely welded together before final installation into the car. I could tip it forward and wrap it out through the passenger side door. Once everything making up the rear structure was completely welded, it was put in place and welded to the car as shown in the second picture. Actually, to complicate things further, I also had the door bars to contend with. So the rear structure was put in place but not welded to the car, then the door bars were placed and partially welded to the main hoop. Then the entire structure was shifted forward to gain access to the remainder of the door bar welds, then finally everything was put in place and welded to the floor and strut towers. This stuff takes careful planning. Quote Link to comment Share on other sites More sharing options...
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