Frame shortening?

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My friend has a '55 chevy truck frame he wants to take 16" out of.  After we cut and fit it, what is the recommended way to brace it?  When a friend of mine did mine, he welded sections on the inside, welded them in and rosette welded two holes on each end.  I've heard not to weld them in "solid", that is to weld them all around.  I thought I'd better get some advice before we begin.  Thanks in advance, Rod
Reply:Try the search function. Use a variety of key words.Such threads as these may appear.http://weldingweb.com/vbb/showthread.php...ght=fish+platehttp://weldingweb.com/vbb/showthread.php...ght=fish+plateCity of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny
Reply:So let me get this straight, you want to take a perfectly good "solid" frame, cut it, shorten it, then weld it in less than "solid?" Ummmmm....think you need to think this approach through. Where is the cut located in reference to the suspension? What kind of loads will it see? Typically a person that comes on here asking these kind of questions doesn't have the knowledge or skills to be performing such a modification. Not to say you don't, but as history would have it, that's how things usually go. Do you have a way to maintain alignment? What process will you use and how skilled are you on that process? Probably a few more questions that need answered before you are likely to get some real solid advice. A sketch or pics would help demonstrate your plans. Help us help you
Reply:Hi BCTimberwolf,  Your questions are thought-provoking..  I thought my friend could just move the springs up but he says he can't.  He didn't ask me to do this checking but I thought I'd better.  When a friend of mine who has done a lot of frame work lengthened my frame he welded plates on the inside and rosette welded them at the ends with two holes about an inch in diameter at each end.  I read a post at one point that said not to weld the plates in "solid", that is, not constant weld all around.  It referred to frame flex.  I don't blame you for being dubious about this.  I'm just trying to get some idea of a plan so I can hopefully get my friend some good advice.  Thanks for your concern, Rod
Reply:You need to have the bare frame on a jig or at least screw-jacks so that the car is on a datum line so correct measurements can be made (much easier if you do this). Then if possible the "new" rear-most brace(s) should be welded in before you start cutting off the frame. This will keep the frame in the correct shape during cutting.In most cases you can get away with cutting out your rear leaf spring mounts if you are adding in say a 4link as it will have new contact points with the frame but still use the front eye-mounts as locators. As for "not welding all the way around" that is good advice as if you make "weld stitches" and one weld cracks it won't be transferred to the rest of the weld (think of rivets...kinda).There are much better people on here than i to give advice on this problem than I but this is at least what i have done on past car projects.
Reply:Hey 1967marti, thanks for the input.  I've also been looking online and have gotten some more ideas.  Your method seems very workable and is similar to the other articles I've read.  Thanks again, Rod