|
|
Hi guys,Im having issues with my welds pulling out of square when TIG welding them. Im using jigs with doing this aswell.I recently purchased (2x) Strong Hand 3-Axis corner gigs and I had two cheapo harbor freight 2 axis gigs for this job. http://www.lehighvalleyabrasives.com...FSdn7AodVXAAJwMaking a 7'x2' rectangular table using 1"x1" 14GA tubing. Everything is cut and mitered on my band saw which I spent a lot of time ensuring that the 90* and 45* cuts are accurate.The process I am using is to do this is this... 1. get the 4 corner jigs out and dry assemble the top of the frame in the jigs, line everything uptight no gaps, and clamp down the jigs 2. I put two tacks the top side of the frame one on the inside 45* miter and one on the outside 45* corner to all four corners. 3. I loosen up the jigs and flip the entire assembly 180* and reclamp it down in the jigs. at this point everything is still square. 4. then I just Tig the entire top 45* miter on all four corners, then go back to the first and weld weld up the outside edge where the tips of the to 45* miters come to make the 90*. 5. remove the assembly and flip 180* so I can weld up the side that I tacked first. Weld that side the same I did the other side. 6. now the only joints left to weld are the inside corner 90* joints. So I remove the entire assembly from the jigs and weld that joint on the bench with out and jigs. I check and somewhere between steps 3-6 the assemble pulled its self slightly out of square. I had this happen to me a few times in the past and know its the shrinkage of the weld that's making it pull.But is there a sequence you guys use when welding rect/squares to make sure that none of them come out of square every time? I thought the jigs would do that for me. Do I need to add more tacks before burning this thing out.... I want to get these done as quick as possible so flipping and tacking each side just adds more time which is fine if it works but I would like to find the fastest way to do this while maintaining the square-ness.Last edited by TTnicksocal; 04-11-2014 at 03:36 PM.
Reply:Fast and square don't always go together. One way to do all of this is to weld one corner at a time. You might have to gap the joint slightly so you can pull things back straight and square after making the 1st outside weld. When done with corner 1, do the same thing on corner 2. Repeat on 3 and 4. Do this enough and you'll get an idea how much things pull when welded, and you can over correct before welding. That way when things pull, they pull straight vs out of square. I've got a set of those sorts of welding squares and I hardly ever use them as is on critical work. I might use them to hold things in place for fit and tackup, but when it comes to welding, I usually just over correct and let things pull straight. I also keep checking square as I go. If need be I'll stop and bend or heat straighten as needed. I don't wait until every thing is done and then try to deal with it. Another thing to keep in mind. Tig can put a lot of heat into the material if you aren't careful. Low and slow is a good way to get excess heat build up. All that heat will want to expand and then contract your work, pulling it this way and that. Many times more amps and faster reduces the amount of heat. Less heat, less pull..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:How about some pictures?
Reply:There was a lot of reading and I cut through it pretty fast. Tack up your joints all over the frame. Tack one corner, flip it and tack the opposite corner of the frame. Flip it again and tack another different corner. Flip it and tack the opposite. Repeat until you have tack welds on both sides of each joint and all four corners. After each tack or two, check for square. After tacking, weld up a corner joint. Go to the opposite corner and weld up another joint. Repeat this process and you should remain square. "Hey I didn't come to look and learn, I came to turn and burn.... If I can't light up, I'm gonna light out!"-JodyIdealarc 250 "Fatman"MM 252MM 211 "Little boy" Victor Torches
Reply:I would clamp or Tek screw diagonal braces to the frame before welding, after cooling remove them . This will help but you still may have some distortion. On that small tube you should be able to tweak it back fairly easy.Miller xmt304, Miller S22 p12, Miier Maxstar SD, Miller 252 w 30A, Miller super32p12, Lincoln Ranger 9, Thermal Arc 181I with spoolgun, Hypertherm 10000 ,Smith torches. Esab 161lts miniarc.
Reply:Why are you Tig welding it?
Reply:Do you for square before you start welding? Are the jigs all square? I usually check diagonals as I go and adjust prior to final welding.
Reply:Here are some picsIm using my TIG welder because the only other thing i have is my crappy flux core Weld Pak 100. The base is intended to end up as some furniture once the wood top and glass is added so the welds need to look nice which i dont think my little lincoln is capable of.I was able to pull everything back square, i got got it pretty much finished just need the mounting tabs on the for the wood top tacked in place.Im wondering why i spent the money on those strong hand jigs if i still need to tweek each one a bit to get it back square. But im sure, like some have said, the TIG is putting a more heat in than what a mig would do and i probably didnt tack it enough before burning it out.
Reply:The strong hand clamp is a great piece but it does not compensate for the shrinkage of different gauge and materials and the welding process. It seems to a very simple concept but it will take years of doing this before you start to win the battle of building a square box.
Reply:Originally Posted by kkustomzIt seems to a very simple concept but it will take years of doing this before you start to win the battle of building a square box.
Reply:Maybe it is square, but the lengths of steel are now slightly bowed,pulling it in. I have 4 good square clamps and still have issues, it doesn't guarantee square, but it certainly speeds things up. Heat affected zone is going to be more with the tig, resulting in more warpage.
Reply:Clamps rarely will hold material from movement when welding. Once everything is tack welded and checked for square you should tack temporary bracing diagonally across the corners. Something like a 1.5 inch angle about 18 to 24 inches long would be good. Weld up moving around not welding up one corner completely. Let cool then snap the angles off. ( Only tack the angles on one edge so that they can be levered off.) On larger frames I tack weld and instead of angle braces I tack weld large turnbuckles in place. If you have a friend who is an electrical linesman.... they use large turnbuckles for telephone pole guy wires. You can final adjust a corner using the turnbuckle after tacking but before welding.
Reply:If you think tig welding steel tubing is fun, try doing them in stainless |
|
发表于 2021-8-31 23:15:18