How thick should tubing on a frame be ?

[Yankee Transplant]

Hello , I plan on building my own frame out of 2x4 tubing ,, My question is how thick should it be ? I was told the thicker is not always better, because of (sag) , I have no clue on this . do I need 1/8 th 3/16 1/4 .. which I think 1/4 will weigh to much IDK??? Im putting a 50 ford cab on it with the 350 sbc and the axle will be in front of every thing.. Id hate to buy this material and it be the wrong stuff , and I sure don't want it to fold up on me going down the road ... 3/16 Maybe ???? I plan on making the (Z) frame I think they call it that ,, where you drop the frame for the cab to sit in .. Thanks for any help ..

 

[itsmecord]

Well, I will warn you that you will get a number of different responses to your question. I for one will be using 1/8" 2x4, and 2x3 to build the frame for my 36 chevy sedan with a 5.3 LS. I know just what your saying about not wanting to spend money on the wrong stuff. I can relate because I bought two 12 ft sticks of 2x4x 3/16 and now it's just sitting behind the barn at my old house because it just seems like it's way more than I need !

 

[Sam_Fear]

With rec tube, 1/8" 4x2 deflects about 1/3 less than 3/16" 3x2. It's the height of the sidewall that makes the biggest difference.

 

[Dirtyrat]

My frame is 3/16" 2x4. There is a lot that goes into sorting out what you need, like span length, number of crossmembers/cross supports, etc...

 

[Yankee Transplant]

height will not be a problem Ive got a 2x4 channel welded into the old frame now and the bottom of the frame is around 5&1/2 inches off the ground . I just didn't know how the span of all the weight would effect it or what I should get to hold it up . Mine already has a stock car frame on it like it is . so all I got to do is measure my drop and build it on my new frame, and it will set the same height , ( I hope )

 

[Country Misfit]

Hey,did you get my message?

 

[Yankee Transplant]

yea I sure did . Still don't know how to do it . But hey , thanks anyway.

 

[kenny c]

check out tetanus tornado 49 f6 in the builds section, it's my truck ,the frame is .210 wall 2x4 tube which is as close to 1/8 as you get. it doesn't sag or flex at all. I welded in internal fish plates in the sides of the joints and external fish plates on the bottom sides of the joints as they are in tension. I bought 48 feet and had no waste and had about 5 feet left over.

 

[Yankee Transplant]

yea I priced two 20 footers at $300 it was 1/8 and just a little more for 3/16 ..I plan on having 4 cross braces including the trans member , may have to use something different for trans member . Depends on what I got left at that point .

 

[Old Iron]

1/8 " is .125 thousands
3/16" is .1875 thousands
7/32" is .21878 thousands
1/4 " is .250 Thousands

.210 is thicker than 3/16" and less than 1/4"

 

[Dirtyrat]

I think he meant to type .120...

 

[Old Iron]

I think he meant to type .120...

Oh, I didn't think of that, sorry
My brain isn't that fast
Carry on

 

[kenny c]

Yea I meant .120 wall. when I'm tired my dyslexia is even worse. Sorry for the confusion.

 

[Yankee Transplant]

Hey I easily to get (cornfuzed) ...

 

[donsrods]

There is no single, correct answer, it all boils down to personal preference and what the builder feels is right. I always go with 3/16 just because I feel better using it over 1/8. 1/4 is way too heavy though.

Don

 

[kenny c]

I think Don hit it on the head. Personal preference. Also frame design, length, welding ability and joint strength. Look through the build section and see what other people have done. Don't be afraid to ask questions, everyone is here to help one another and not trying to cut anyone down. just friends trying help friends.

 

[Yankee Transplant]

I kinda thought the 1/4 was too much also. It depends on the front axle set up I can find , on the location of the springs . that will either narrow the spand or lengthen it . I have an axle that's a single spring set up , its just the axle (no spring) but it is really ruff . I don't know if I can trust it , so I will look for a while yet .. I'm still collecting parts Thanks for the input guys.. When I finally get my tubing ordered I will start a frame build and maybe yall can keep me strait on it .

 

[RPM]

We build a lot of frames and we always use 3/16"

 

[Yankee Transplant]

Thanks RPM . I was kinda leaning toword the 3/16 shame I didn't live closer to itsmecord

 

[bruno]

Mike at Cornfield Customs said he only uses 2x4 3/16.