frame metal thickness

[tburnett]

I am building my 31 ford and the frame is in pretty bad shape. My friend can use the rear section and wants to trade the frame for 2 11' sticks of 2"x3"x1/8" rectangle tubing. My 31 is a fourdoor that is going to be driven daily with a small block 302. The "free" steel is appealing as I am building on a budget, but is it too thin? I have heard that it is fine, but 3/16" thick is more commonly used. What are you guys thoughts?

 

[Dragons]

I use 2"X3"X.120" wall all the time. No issues.

 

[Fox Fabrication]

.250" wall....It's nice to have something you can drill and tap to mount misc stuff off of.

 

[RPM]

We build a lot of frames , mostly for T Buckets. We use 2 x 3 3/16, some times we will use 1/4 if it is getting a really hi HP engine.

 

[35Mastr]

I am going to use 2x3 .250 wall. I like to tap and thread when needed also.

Plus its all new and was all free.

 

[roddguy1]

All the previous posts make very good points that are all valid conciderations. Personally I'm more comfortable with 2x4 if it"s only .120 (1/8th") wall. However, I'm sure if you build it well with proper gussets and cross bracing and good penatration welds ( I like to v butt my joints ) it will be just fine for your project. Just don't over HP the thing. One more thing to think about as well. If you build in a good metal support structure into the body to replace the original wood, such as 1x1 and 1x2 inch tubing, this will become part of the over all support of the entire car when it's bolted to the frame. If you check out my build thread

http://www.ratrodsrule.com/forum/showthread.php?t=8475

you will see an example of this. The frame on this car was so weak it would twist like a double helix. Once the body was bolted down to it, it tightened right up. Thats not to say your frame would do that thought.