Is this a legal butt weld splice?

[andrewb]

I’m unable to find any company that can bend 1-3/8 x 0.058 4130 tubing with a 6” radius. Well, I did and they want $500 for 4 bends. Now I know why most chassis builders use larger diameter and thicker tubing… they can make the bends on a manual bender.

I need a wider shoulder hoop than what’s available (Mark Williams, The Chassis Shop) because I’m 6’5”. What I’d like to find out if I can use a 2” spacer to widen the shoulder hoop with an interior sleeve. It needs to meet the SFI Spec 2.6A (7.50 Seconds & Slower). They allow for a single butt weld splice in the center of the upper frame rail, I just wonder if this is legal as well.

Thanks,
Andrew

[dreracecar]

1 3/8 x .058 is not a problem for my bender and I only charge $12.00 a bend as long as deg. are givin to me , If I have to figure out the bends then it becomes a $60 min charge.

That being said, there is nothing wrong with what you show. Personally I would put the split underneath the cage uprights if running a 6-point cage.
Also I would also overbuild the 7.50 spec to 2.4 anyway since the only real main difference is stepping up the shoulder hoop to 1 1/2 x .058 and going foward to 2'' ahead of the rear end uprites, that way you can insert the 1 3/8 upper tube back to the shoulder hoop bend and cover the requirement of an internal reinforcement tube beteen the foward roll bar hoop and the front seat uprite.

[andrewb]

dreracecar,

I've considered going to 2.4 but will stick with 2.6 for this build. I'll PM you with details.

Andrew

[fuel749]

While it's potentially legal, no doubt it will face extra scrutiny from tech inspectors and future buyers. Mostly because if people don't see things a certain way often enough they don't believe it can be done that way. Like Bruce says, 1.375 x .058 on a 6" CLR is no problem for most of the benders we use. Have him bend your tubes and be done with it. Even if I don't go for the 2.4 upgrade, I make all my shoulder hoops out of 1.5 x .058 (unless the cage will be over 18") for a couple of reasons.

[dreracecar]

I got the job and tubing has been ordered.
Most chassie techs just look at dia and wall thickness for the frame and rarely get into the construction since most of the time the car is together and not bare chassie. If construction and welding were considerations when inspected, my business would be 24/7 right now

[hotrod316]

bruce is right, any good shop will have a bender that can do that size in that radius. ours can and did that exact bend for our new 6.0 fed. and  $12 is cheap to bend a tube.  i wouldnt have done it that cheap before the hydraulic conversion, but i got big muscles now that makes squeezing the bend button super easy  and i would still charge 20 for each bend.

matt
Lefty'sRodShop
SMRacing