Back half question...

[Spray-Bomb]

Is 1/8" 2x4" square tubing big enough for a back half ???

Thanks, Matt

[nhtc33d]

When i built my step notch i used 3x4x3/16". The 3x4 is a very nice match for the stock 63-66 frame rails. I am no professional(but i did stay at a holiday inn last night!) but i think 1/8 is too thin.

[orange71]

My Back half was built from 2x5x.120 with the proper gusseting you wont have any problems. http://sportruck.com/events/blood-drag-2008/i32.html

[Spray-Bomb]

Thanks guys

[scotts62]

2x3 .120 for me

[FnLow69]

my first backhalf was done in 3/16... but my new frame is done in 1/8 (.120) wall and is pretty standard.

[Twisted Minis]

I use 2x4 .120 wall for the backhalf on just about everything.

[abadsvt]

I agree with twisted mini's that the .120 is plenty strong. I don't know if you have felt the weight difference between .188 and .120. It is quite abit heavier which is just all extra weight. Plus a properly built back half with proper bracing would be plenty strong with .120. That is just my opinion though.

Josh

[PBFAB.COM]

Originally Posted by Twisted Minis

I use 2x4 .120 wall for the backhalf on just about everything.

Agreed!

I have been using the same material for all my back-halves and chassis. I use the "HRPO" steel... it doesn't have all the mill-scale and looks a lot prettier.

[abadsvt]

Originally Posted by porterbuilt

Agreed!

I have been using the same material for all my back-halves and chassis. I use the "HRPO" steel... it doesn't have all the mill-scale and looks a lot prettier.

You know ever since you first told me about "HPRO" i have look all over and can't find it. My steel supplier didn't even know what it was and they are a large complany. Maybe i need to move to Arizona to get the good stuff.

Josh

[PBFAB.COM]

Originally Posted by abadsvt

You know ever since you first told me about "HPRO" i have look all over and can't find it. My steel supplier didn't even know what it was and they are a large complany. Maybe i need to move to Arizona to get the good stuff.

Josh

I kind of found out about it on "accident". I always wondered why the sticks I got never looked as clean or pretty as the rails some of the larger chassis builders had (Art Morrison, Chris Alston). One of my orders came in and it was the cleanest I had ever seen... they made a mistake and sent me the "HRPO" (hot rolled pickeled in oil) instead of the regular stuff!

During some price shopping, I talked to many other suppliers who had no idea what it was. Needless to say I have been buying it from the same supplier for the last several years.

[scotts62]

Thats cool good info, i havent even heard of that kind.

[XXL]

Originally Posted by porterbuilt

"HRPO" (hot rolled pickeled in oil)

Is this anything like "DFSR" (deep fried and slathered in Ranch)?

[Twisted Minis]

Ya try picking up a whole stick of .188 wall on your own. Lol. I don't think I can do it. But as abadsvt said proper design and bracing and it will be plenty strong and still light weight.

Can I assume you know how to use a shear load gusset? Or a fish plate?

[abadsvt]

Yeah when i started my very first build i ordered 2 sticks of 2x4 .188 tubing. I off loaded it off my truck then realized there is no way in hell I am building a frame out of this heavy #### and reloaded it then droped it back off at the supply house. When you mention shear load gussets are you refering to gussets on both sides of the frame joint to reinforce the welded joint? If not do you mine explaining?

Josh

[Twisted Minis]

Just a flat plate welded over the top of a weld where to pieces of tube meet. Usually triangular in shape to reduce stress risers. This kind of thing.

[abadsvt]

Originally Posted by Twisted Minis

Just a flat plate welded over the top of a weld where to pieces of tube meet. Usually triangular in shape to reduce stress risers. This kind of thing.

Thats what i thought. Just never heard that verbage before. Thanks for the clarification.

Josh

[AceX]

My room mate and I are about to start building a new frame for his s10 out of either 2x3x1/4 or 2x4x1/4.

Seth! When the hell did you sign on here!?

Everyone, if you haven't heard, Seth (Twisted Minis) is one of the most awesome fab/builders around! On top of that he has some fun stories to tell!

[Twisted Minis]

Just a few days ago. Got an S10 project in the shop so I joined, Had been lurking for a bit though.

1/4 wall is really quite excessive, and in all honestly will probably be weaker than a thinner frame. It takes a lot more prep and heat to weld to, so the joints may not be as strong. Also the frame tube is less likely to flex, which transfers the stress of every bump, driveway and speed bump into your welded joints. Some flex is a good thing. You just have to know where to put it.

[AceX]

We're taking the frame and hacking it off at the firewall, then using the tubing to do a SFBD, then at the headboard we're utilizing a Chris Alston back-half kit which uses mandrel bent tubing.

My room mate is the Wyotech grad, not me. I'm a relative newbie when it comes to suspension work and, its his truck, I'm just in it so I can learn to weld and get some chassis fab experience. In return, I teach him how to build ear bursting sound systems and do fiberglass work, along with wiring and tuning.

[Twisted Minis]

I'm going to have ti look into that. I've been using Rapid Strip wheels to remove all the mill scale when I TIG the tube together. Having the mill scale removed would be worth some extra cost to me.