frame questions

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tiny1

Callin' him Tiny is like callin' Dirty Harry a bea
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May 18, 2007
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I haven't found a truck cab yet still looking. But i was wondering what size tubing is everyone using to make the frame for the trucks . Just looking at some of the pics I've seen it looks like maybe 2 x 4 ? I was wondering how thick would be safe to use? And about how much tubing does it take to build the frame just off hand.

Well while I'm asking all the dumb questions the z'ed frame looks weak to me But I've always over kill everything i built. Is there every a problem with the z'ed frame ?

Thanks
 
Frames!

I haven't found a truck cab yet still looking. But i was wondering what size tubing is everyone using to make the frame for the trucks . Just looking at some of the pics I've seen it looks like maybe 2 x 4 ? I was wondering how thick would be safe to use? And about how much tubing does it take to build the frame just off hand.

Well while I'm asking all the dumb questions the z'ed frame looks weak to me But I've always over kill everything i built. Is there every a problem with the z'ed frame ?

Thanks

Tiny,
Most guys r using 2 x 3 stock to save weight although that varies depending on app or preference. I'm sure someone will be glad to say how many feet it takes or they buy. Most guys weld xtra support to z'd sections... usually diamond shaped plates but everyone has their own ideas. Oh yeah, after seeing how *small* u r... u mite want to reconsider & use 2 x 4 stock!!! ; - >

BoB
 
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Depends on the truck, Going back to full size, 2X4 or 3X4. Hot rod style 2X3 is plenty with a 3/16 wall. I have seen 5 inch frame rails before but the guys running that stuff are running lots of weight. Bucket style frames run two rails at about 10 feet each side. A lot of guys run a round tube up front, for the leading cross member. Stepping the frame up and down does change the strength, but if it is done right, I think it is stronger. yes, stronger. Kind of like breaking an edge in sheet metal keeps the sheet metal from bending. It may be no different but it takes the spring out of the long frame sections.
 
Very good points. The diamond side supports are a must on butt welded miter joints.
Also keep in mind that you should build a "grid" that attaches to the floor area of the body and ties into the vertical sections of the body.

I use 1x2 rec. tube. This will add strength to the chassis as well. If you add a bed to your rat, you can "grid" the floor area of the bed as well.

The "grid" I'm speaking of comes off with the body and bed. It's a skeleton of tube that follows the shape and contour of the chassis.

I hope I explained it correctly. If not give me a du huh, and I'll go more in depth.....:)


Tracy
 
I use either 2X3 3/16 wall or 2X4 1/8 wall depending what I'm building a chassis for. Other than the ones that the suspension are mounted to, I usally make cross members out of a combination of 1.5" and 1 " round tubing. If reinforced properly Z'd frames are not a problem. If you use a roll cage like Bonehead did in his truck, most of your possible chassis strength issues are pretty much taken care of.
 
Mine is mostly 1 5/8 round tube with 3x4 on the rear section. Inside is a full cage.
 

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Thanks for all the input guys :) It was a great help. I go to bed thinking about building one and wake up with it on my mind. :)
 
Also

TINY,
Maybe Don or one of the guys will post a few pictures of how he adds the interior buttressing of the z'd parts for support!

BoB
 
TINY,
Maybe Don or one of the guys will post a few pictures of how he adds the interior buttressing of the z'd parts for support!

BoB

cool i read pictures better than letters lol . Going to look at a 48 ford today may be the one :)
 
TINY,
Maybe Don or one of the guys will post a few pictures of how he adds the interior buttressing of the z'd parts for support!

BoB

Ok, you've talked me into it. :D :D

Essentially, when you are welding two pieces of steel together, if you can add a backing piece of steel to them, you can crank up the heat and get a weld with better penetration than if the backer was not there. So, what we do is cut a little piece of flat stock so that it will slip inside the first piece (into which we have drilled a couple of little holes in the edge) and we rosette or plug weld that backer into place. Then we slip the second piece of steel over the backers (we put a backer on two sides of one piece of tubing) and fully weld around the perimeter.

These pictures show that process.

Picture one is the frame rails just laid out loose to check for straightness and kickup amount.

Picture two is one of the little backers we make.

Picture three shows the holes we drill through which we will weld the backers temporarily in place.

Picture four show the backer clamped for welding.

Picture five is one of the backers rosette welded into place.


Don
 

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Once that is done, you can clamp the rails down to a jig or welding table so it won't pull while you are welding it, and fully weld up the two pieces.

After we get the kickups welded in place, we move the big frame sections to our homemade framejig to clamp it down perfectly square for final welding. I have seen some guys even make a jig from plywood and pieces of 2 x 4 lumber, and that is fine. Anything you can do to keep the frame from pulling and be in perfect alignment is good.

Don
 

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We've started doing our front tube crossmembers a little different than we had. Originally, we did them like this, in the traditional way. We always use tubing from Total Performance because it is something like 2 and 3/4 inch diameter, which you can't find at most steel supply houses. It slips into a 3 inch piece of box tubing frame rail, and leaves material to wrap around it. Plus, they sell you the piece for like $ 25, so it is a deal.

Don
 

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But Dan found a better way to do them. We now punch a hole all the way through both sides of the tubing, and insert the round tube all the way through. That way, you get a full weld all the way around the tube, rather than only about 3/4 of the way around it. Much stronger. We use two of the holesaw plugs to cap off the Total Performance tube crossmember, and weld them in place. Then, when you insert these capped tubes flush with the outside frame rails, it gives you a perfectly flat outside wall after a little grinding.

Don
 

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