tube frame question

I was wondering if any one knew what type of dimension tubing would be needed for something like this that I saw in the "Parts With Appeal" section in HRD

 

anyone anywhere

 

I can't see what you're talking about in the picture. It's too blurry.

 

freebird...I can't tell what you are trying to build from the pic.....what is it and what is it used for?....

 

Just a wild guess to draw in someone that really knows their s#!+ 3" dia x 1/8-3/16 DOM

 

I would see what the section modulus is for a rectangular 3" X 2" X 3/16" wall tubing. Then select a round tube that has that same or nearly same value. That info can be found in an AISC Steel Construction Manual. The section modulus for the rectangular tube is 1.24. I could not find a catalog for steel tubing but a 3"standard wall (.216) pipe has a section modulus of 1.72. 2-1/2" XS pipe (.276 wall) has a section modulus of 1.34.
You could do the same exercise for a 2" X 1-1/2" X 1/8" wall rectangular steel tube & still be safe. My catalogs did not have that size tube. A steel service center should be able to furnish that data.

 

thank you, thats what i was looking for. What it was in the pic was a signal tube on each side running as the frame. I was asking because I was searching in dimensions and all I found were multiple tubes and was wondering if just one would work ok.

 

There some good info about single tube frames in this old thread ...

http://www.jalopyjournal.com/forum/showthread.php?t=196169&