Welding Project went bad Why ?????

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I have spent months thinking and designing a machine, and many many days fabricating the metal parts to be welded together. Fitted together every thing just fine and welded 80% together. Then yesterday Friday welded two 2x2x.25 thick stainless steel (SS) angle irons 10 feet long onto the 4x4x.25 thick non stainless steel tube and the 2x2x.25 angles warped.Welded the top of the tube, with the SS angle iron (so that the bend of the angle is .25 inches above the level surface of the tube) from the center of the length out to ends on one side then the other side and then welded the bottom of the angle iron to the center of the tube, from the center to the outside. The free angle leg of the SS angle that was not welded lift up ( the 4x4 tube has rounded corners and the weld pulled the SS angle into  towards the curved corner of the tube) it was pulled up so that the flat surface that I wanted and need for mounting another part of the machine is not there. Now the out side edges of the SS angles are about .25 inches higher then the bend of the SS angle on both SS angles. And the SS angles are not flat they are wavey along the 10 foot length.The SS angle was welded every 6 to 8 inches with a 2 to 3 inch weld. Now I needed a flat surface across the free angles (not welded to the tube) on both SS angle iron pieces and not bowed up .25 inches on the out side edges and a flat surface not wavey.Did not notice this until I was done welding the SS to the tube.Any Idea what went wrong?How can I weld these SS angle irons on to the tube with out them distortiing so bad.Yes I will have to get new steel and refabricate the steel parts that went bad.What ever DETAILED ASSISTANCE YOU CAN GIVE ME , believe me it will be greatly appreciated.Used 308 SS stick rod and welder was set at 150; SS is alloy 304; tube is AR36Need the top of the SS angles to be flat so I can move/slide a part of the machine along the surface.Its a drill with the drill moving up and down the mast.Last edited by burntside bob; 02-27-2010 at 11:48 AM.
Reply:Again, not enough info. What kind of SS? What kind of welding, stick, mig, Tig? What filler?Sorry, missed the last lines.Last edited by transit; 02-27-2010 at 12:04 PM.
Reply:What welding process are you using?Got any pics? I can't visualize the issues too well from your description.Rex
Reply:Several options here: 1.Refractive bending; ie. bend the opposite direction before you weld, and let the welding heat pull the part back straight. 2. Preheat and post-heat to minimize distortion. 3. Variety of leather and rubber mallets, and blocks. Whack it back into shape before it cools. 4. Clamps and more clamps/ jigs. Rule of thumb; if you are building with a flat edge desired, clamp it to a flat seriously heavy table to keep it pinned in place, or jig it up to keep it where you want it.5 Drink beer and throw a fit; usually a 3lb maul will help you destroy the project and relieve your stress. I usually recommend #5 as a last resort......Please post up some pics, and give us some fine details; where you start the weld, and what pattern if any is used to weld the angle to the sq. tube.From what I am reading in your original post, we are either talking about a SS duck blind frame, or a rack to hold Buick cylinder heads on............not quite sure which, although the drill involved makes it more interesting!!!!Last edited by Rojodiablo; 02-27-2010 at 11:55 AM.And then, after so much work...... you have it in your hand, and you look over to your side...... and the runner has run off. Leaving you holding the prize, wondering when the runner will return.
Reply:what's happening is, when you weld, #1 you have alot to fill because of the curvature of the tubing edge and rolls the angle up from the shrinking of the filler metal (causing the warping).. #2, too much weld.. stitch weld it.. personally, if i could, i would drill 3/8 holes every 6 inches (alot i know) where the flat of the tube will be in contact with the angle iron and plug weld it.. maybe spread 'em out to a foot apart instead of 6".. then lay down a bit more weld if needed..if you're not livin on the edge, you're takin up too much room..
Reply:All I can read is stainless rod at 150 amps.  What size rod?  I think that is too many amps for 1/8" rod.Tack in many places before welding.DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:Okay, with some visualization of your project, I am assuming the angle will be a track for the drill to ride on. If so, then I suggest you make a frame/ skeleton jig to hold the tracks in place completely while you weld on this. Knowing what I know about SS, this is going to want to warp whether you stick or tig it. If I were making a solid frame to hold it, I'd really consider how the track will want to tweak on you, and go from there.Another thought; how about welding on say 10 tabs, and then bolt the track to the tube? You can molest and straighten each tab after welding them in, and have the track pretty dang straight. Then, being sure you have slotted holes so you can adjust it, just drill, tap & bolt the tracks in place. It's a whole lot easier to bend 10 1-1/4"x 1/4" tabs than 1 piece of 10"x1/4" material.And then, after so much work...... you have it in your hand, and you look over to your side...... and the runner has run off. Leaving you holding the prize, wondering when the runner will return.
Reply:Some pics would be nice, Im trying to visualize this but I havent got any coffee yet this morning and I dont want to strain my brain.  I know this is weldingweb and all but have you considered machine screws or... bolting it in some fasion??Last edited by pilebuck; 02-27-2010 at 12:56 PM.2011 Dodge 3500 diesel duallyLincoln SA-200Lincoln SAE-300LN-25'sLincoln Idealarc R3RMiller Trailblazer 302
Reply:Is this what you have?If it is, then drill/plug weld or drill/bolt would be your best bet.  If you really need the strength of a weld on the backside of the angle/radius of the tube, then put a  1-1/2" long stitch every foot or so. Before you stitch it, tack weld a piece of angle or flat bar between the up facing legs of the angle at each spot you are going to stitch. This will be a temporary brace (temp) that will be taken out after the weldment has cooled. Weld a stitch on one angle and then move across and weld the same stitch on the other angle. The temp brace make the stresses in the angles fight against each other. Make sure the weldment is completely cool before you remove the temps. You will have to grind/sand the tacks that held the temps on and you will likely still have to massage the angle with a hammer to make it perfectly straight. One last thing, this probably didn't have anything to do with your warpage problem but it is something to know. When welding dissimilar metals, like stainless steel to A-36 steel, use an odd numbered stainless electrode. 304 stainless to A-36 tube use 307/309. 304 stainless to 304 stainless use 308/316. Attached ImagesWill
Reply:Have a good idea of what you are trying to do, but as asked above provide pictures, or drawings of what you are trying to duplicate, perhaps it is your engineering, alot of this precise stuff is double bevel, and are alot of other ways it can be done.Went back read your submision, what kind of drill, water well? Thats an awful large drill..........Last edited by pistolnoon; 02-28-2010 at 12:56 AM.