Chasi Rule Confusion

[raptor93]

Can anyone please confirm if this design of our chasis is complying to the rule stated below-

T3.5.5 If a bent tube is used anywhere in the primary structure, other than the front and main roll hoops, an additional tube must be attached to support it. The attachment point must be the position along the tube where it deviates farthest from a straight line connecting both ends. The support tube must have the same diameter and thickness as the bent tube. The support tube must terminate at a node of the chassis.
Attached are the images of our design.

[AxelRipper]

First off, I am going to suggest asking the rules committee for sure.

Second, which tube are you talking about? If you are talking the bent black tube, that technically is not defined by the rules, so it does not have to be braced at all. If you are talking about your blue tubes in side profile (the third picture) then yes, you have it done correctly from what I can see. However, remember that in the rule you referenced "The support tube must have the same diameter and thickness as the bent tube" and in this case that bent black tube would be the support tube.

Hope this helps.

[raptor93]

Dear axel ripper, thanks for your prompt reply.

1. I was talking about the black bent tube. I'm afraid we havent complied to the rule "the attachment point must be the position along the tube where it deviates farthest from a straight line joining both ends" also the support tube attached (blue) has same outer dia but, lesser inner dia as compared to the bent rod(black) .

2. Also, is the overall configuration of the front bulkhead okay?

3. Another problem is that the front roll hoop(green) after fabricating, now has a weld in the center. Is there a need for any sort of gusseting or any other support structure?

[slicktop]

I am not sure that the blue X braces from the front bulkhead to the front hoop are considered part of the "primary structure", dont think they are, but its been a while since i've looked at the rules. I believe your X braces are only required if legs and feet are not below 49 wall. The black bent tube is not required as Axel Ripper said. Would help if you gave information on your wall thicknesses.

If your front roll hoop was constructed from two pieces of tubes that were welded together, I don't think that passes.

Where is the front hoop support?

[Big Bird]

AAARRGGHH! Tubes and nodes all over the shop - yet the only evidence I can see of a load input point (the pullrod rocker pivots) is in the middle of an unsupported tube (bending loads....)

Once again, your chassis is just a big bracket. You design the bracket when you know where everything else is going - not design the bracket and then make all the components fit.

[Michael Royce]

Raptor,
Take Big Bird's advise and re-evaluate your design.

Then, instead of asking this forum, send your question into the competition in which you are entered or plan to enter to get an official response. All yo will get here is opinions!! Some good, some ???