Tube chassis question

the 180* shoe! for bending the funny car cage bars! Other than that I don't think it would be needed.

I took a look & this is the bending dies I have........

1-5/8 x 90* x 6.5 radius

1-1/2 x 90* x 6.5 radius

1-1/4 x 90* x 4.5 radius

1 x 180* x 3.0 radius

3/4 x 180* x 3.0 radius

The mistake I made was not getting my 1-1/4 die in 180* since a 180* bend is ideal for making a lot of the smaller front mounted fuel cell's 1-1/4 tubing guard.



Probably 99% of the time a 90* die is all that is needed for the bigger 1-5/8 & 1-1/2 OD cage tubing. I really don't see a need for the 180* dies in these bigger size tubes for cage/frame work, even for the FC cage. Plus the 90* dies will bend a little past 90* if needed, something in the 100-105* range (if I remember correctly). You really only need the 180* dies in the smaller tubing sizes.

It should be noted that for the faster SFI legal mild steel FC cage designs, most of the inner FC structural bars only need to be 1-1/2 x .108+ tubing (vs the bigger 1-5/8 x .118+ tubing). But for the slower NHRA rule book specs the only reason for needing anything remotely resembling any part of a FC cage is if the driver's helmet is behind/under the main hoop. Then "additional tubing" the same size as the roll cage (doesn't say how much) must be added to protect the driver.

Thanks Dave and everybody else, thats a big help with all your guys knowledge, I appreciate it. I have a neighbor in the steel supply business, she's going to give me a quote for some material.

I am reconsidering just seeing if my current cage would even pass a sonic test, but it's a stick welded cage that's 1 3/4" x .120 wall ERW. I think this would be a stretch (No Pun) where the material is concerned, but I think it would be a whole lot easier to restart from scratch, with the added benifit of updating the cage design as well.

I have some shots of the car here, tell me what your opinion is.....

https://s264.photobucket.com/albums/ii185/ssexton1966/

Shawn if it was stick welded I do not think it will pass and needs to be redone, stick is not an accectible way for any racing except maybe dirt burners..... or crash box derby cars....must be Mig with mild steel or Tig for mild steel or chrome moly..




Randy

Sorry, forgot to add that if I could pass sonic test, I was thinking of redoing all the welds on the cage, but that would be a lot of grinding and would be a lot easier to just cut it out and weld in a new cage.

What do you think?

just depends some welds can be fixed by Tiging if you get enough penetration but Dave will have to le you know if that would even be acceptable being it was stick welded.... But I agee it might just be easier to just start over and do it right.....


Randy

the Coug wrote:just be easier to just start over and do it right.....

Exactly, makes no sense going back over the stick welds trying to hide them from an inspector with either a Mig or a Tig pass.

The Mig pass won't hardly burn in at all. It will just pile up a mountain of weld on top of the stick pass. And if you really crank up a Tig welder & try to burn in a full sized Tig pass, it's a good bet that you will have puddle blow-outs as you run across impurities/trash/junk/slag hidden in the stick pass. Not to mention generating even more weld heat at every weld joint again probably isn't the best idea for base material's strength.


As for the old .120 wall ERW tubing passing sonic or not, that's a coin flip either way. I know that for years steel salesmen have told me that the "industry standard" for mild steel's advertised wall thickness tolerances was plus .005" to minus .009". So that meant that a piece of "so called .120 wall" tubing could be as thin as .111" and still be sold as .120" wall to the unsuspecting public.

Shawn, out with the old and in with the new!

'65 T-BOLT wrote:Shawn, out with the old and in with the new!

That's a big 10-4!

DILLIGASDAVE wrote:

the Coug wrote:just be easier to just start over and do it right.....

Exactly, makes no sense going back over the stick welds trying to hide them from an inspector with either a Mig or a Tig pass.

The Mig pass won't hardly burn in at all. It will just pile up a mountain of weld on top of the stick pass. And if you really crank up a Tig welder & try to burn in a full sized Tig pass, it's a good bet that you will have puddle blow-outs as you run across impurities/trash/junk/slag hidden in the stick pass. Not to mention generating even more weld heat at every weld joint again probably isn't the best idea for base material's strength.


As for the old .120 wall ERW tubing passing sonic or not, that's a coin flip either way. I know that for years steel salesmen have told me that the "industry standard" for mild steel's advertised wall thickness tolerances was plus .005" to minus .009". So that meant that a piece of "so called .120 wall" tubing could be as thin as .111" and still be sold as .120" wall to the unsuspecting public.

Yup, know exactly what you mean about weld pile up!

As far as the tubing goes I don't even have any scrap left to measure from! Oh well,

guess I'll take the dive in and ge started on a project!

Oh well,

guess I'll take the dive in and get started on a project![/quote]

just do it! that's what I did...I cut mine up just to make the steering work better rac placement was wrong in my car, they way to fix mine was to move engine back a few inches in the chassis. now I am basically building a new car.

'65 T-BOLT wrote:Oh well,

guess I'll take the dive in and get started on a project!

just do it! that's what I did...I cut mine up just to make the steering work better rac placement was wrong in my car, they way to fix mine was to move engine back a few inches in the chassis. now I am basically building a new car.[/quote]

I know what you mean...Start out doing one thing, and it will grow a life of it's own!