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I recently purchased a 2'x4'x1/2" plate for a small welding table. I didn't notice that the plate had an approximate 1/4"-3/8" bow in it longitudinally. I need this plate much closer to flat before I weld it to the table since the frame is only 2" x 11 guage. I've tried 3 methods to straighten it without avail.Method 1: F150 sitting on the plate with 3/4" blocks at either end of the plate. The plate reverse bows about 1/4" while the truck was on it. However, it springs back when the truck is removed.Method 2: Heated the plate on the convex side with a propane weed burner for 5-10 minutes then doused it with water until cool. *@#$&* No ChangeMethod 3 (see pictures): Mounted it on a scissor table with 4"x6" wood above and below then pulled each side down with a 2 ton cable puller (come along) on each side. The plate would reverse bend approximately 1/4". I didn't try to pull it more because the eyelets started to open under the force (see picture). Sproing......right back to the original reverse bend.I wasn't sure if running stringers on the top of the curve would reverse the bend of 1/2" plate. In addition, I didn't want to waste any more time today grinding them down if it didn't.Question 1: Does anyone think the "come alongs" will work if chains are used around the 4"x6" wood instead of the eye bolts? My best option may be to speak with my supplier and see if an exchange is possible (Two 1/4" plates since they will be easier to flatten??).Any opinions?Thanks in advance. Attached Images
Reply:use those cables and pull the thing flat to the frame and weld the bastard in place...
Reply:This maybe dumb or wrong but just a thought. how about 2 And 3 together. hook it up with the come alongs heat and tighten slowly. then quench. i dont know if this will work so maybe wanna get another opinion before tying. good luck bud
Reply:Also agree with what soco said.
Reply:Joe,Frame straightening, metal bending is as much an art form as it is a science.I'm sure there are others here with more experience in this area, but I've successfully straightened (not milled finish straight but straight enough for a welding table) a few.I don't think any of the methods you've tried are going to be successful.Here's my recommendations. Not fast, not easy, and no guarantees.I'd start by running a few skip beads across the plate. By this I mean weld a 2" bead, skip 2", weld a 2" bead, skip 2", etc, etc.Let cool. Grind down. Check for movement.Don't try to do the whole top at one time. Work in smaller sections. That way, if you overpull the material, you can flip it and reverse the process on the other side.You may find that say a 1" bead works better than 2" etc, etc. If you don't get sufficient movement the first time try more bead, less skip, etc.I really don't know of any "shortcuts" to what you want to accomplish.Taking the piece back and exchanging it for two pieces of 1/4" is not going to solve the problem. 1/2" makes a much better surface for a welding table. Two sheets of 1/4" have a much lower resistance to bending than does a single sheet of 1/2"Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:Originally Posted by jimmiespencilAlso agree with what soco said.
Reply:Thanks for the quick replies.Socoj2, Jimmiespencil and Sandy, The table does have a cross piece in the middle. However, the reason I didn't pull the plate down and weld it to the frame (center first) is because the frame is only made of 11 gauge steel. Since my truck and the come alongs were not strong enough to straighten the plate, I figured the plate would have enough spring force to pull the frame out of square once the welding is finished and the come alongs are released. Id have an even bigger problem if that happened. However, I could be wrong. I've obviously been wrong 3 times so far. SundownIII,I've heard others advise running stringers on the convex side to correct warpage and I agree that this is probably the best remedy to prevent wasting any more time. Flattening the top first and then welding it to the frame while not under stress was what I was trying to accomplish. However, I was looking for a quick fix and ended up wasting time in the end. I should have run a bunch of stringers in the first place. I was trying to avoid the daily grind. Thank you all again.
Reply:If you was close enough I'd just throw it on the press and straighten it. Next is the improvise mode. Somewhere on this forum is a thread about using a chain and hydraulic jack to do just what you need to do. Now it needs to be a pretty darn heavy chain to handle 1/2" plate. Also did you use the front or the back wheel of the truck to run over it. The front would be heavier without anything in the back. Or add more weight to the back of the truck.Millermatic 252XMT 304'sDynasty 280DXHypertherm PowerMax 1250Miller Trailblazer 302 EFIOptima PulserXR feeder and XR Edge gun and more athttp://members.dslextreme.com/users/waynecook/index.htm
Reply:Weld the eye bolts closed first, then flatten it out with your pullers like you did. Weld the underside to pull tension flatward, which means you are welding overhead. When you get it close to flat, you might go ahead and weld it to the frame, (Welding 11 gauge tube to 1/2" plate will be fun!) which will add more tension. You can always put adjusters on the legs for feet. Of course, enough tension might rip the frame to shreads. (I used a forklift and the curb under one edge to bend heavy channel before, but that was a sharp bend, and the flanges were cut!)Last edited by tanglediver; 05-23-2010 at 08:27 PM.City 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:I would think that the best approach would be to bend the plate until flat, or a little beyond, and then apply heat while it is bent. If you bend it without heat, it will spring back when the stress is released. If you bend it and then heat it, some of the bend will become permanent. I used this technique to bend a curve on one of my sculptures.Not sure how hot it would need to be, I would think at least dull red. The hotter the plate is, the less spring back there will be.I don't know what you might have to work against to bend the plate, but it might not matter that much, as long as whatever you were working with was stiff enough to bend the plate.RichardSculptures in copper and other metalshttp://www.fergusonsculpture.comSyncrowave 200 Millermatic 211Readywelder spoolgunHypertherm 600 plasma cutterThermal Arc GMS300 Victor OA torchHomemade Blacksmith propane forge
Reply:1. A flat surface and a sledgehammer, concave side down. (A simple understanding of Newton's second law of motion. Acceleration depends directly upon the net force acting upon the object, and inversely upon the mass of the object. As the mass of the object increases, its acceleration will decrease. Consequently, you can often generate more force with a lighter sledgehammer.) 2. Makeshift hydraulic press3. Bring the part to a hydraulic press
Reply:OUCHBarring heat treatment.....................Turn curved side down, apply strain to both free ends (this also will be easier than trying to crush the middle as you've been doing), and start to weld from middle to the outside. As the welds cool, they'll shrink, and reverse/straighten the bow out. The outside of the curve was stretched when the plate was initially bent out of shape, and shrinking this side will help to pull it true.Instead of the wood thing, use a good chain or two. Or some configuration which will take the stress.What this will do to the frame is another question. I have a feeling as the welds cool, the bow will be relieved, but I'm not sure how the cooling welds will pull the frame. If the frame does pull, there's ways to straighten it too.You might not be in as bad shape as you think. 1/4-3/8 doesn't sound bad over 4 feet."Any day above ground is a good day"http://www.farmersamm.com/
Reply:Originally Posted by irish fixit Next is the improvise mode. Somewhere on this forum is a thread about using a chain and hydraulic jack to do just what you need to do. Now it needs to be a pretty darn heavy chain to handle 1/2" plate.
Reply:I'd be willing to bet it'll be easier than you'd think.Before going out and buying stuff you may never use again. Try using 3 or 4 good c-clamps on both ends. 6" clamps exert a lot of force.In addition.........plate isn't very sturdy. Not enough cross section to form a good web. It's why it bent in the first place. And, until it's actually welded to the frame, it's pretty pliable.But anyhow see how the clamps work, it's a good start, and you can always go extreme if you need to later on down the road Attached Images"Any day above ground is a good day"http://www.farmersamm.com/
Reply:Rather than welding it to the 11ga (haha) and getting it to hold w/o warping up the frame, how about a heavy strongback? Maybe 2 or three down the length...like 1/2x3 flatbar on edge, some heavy square tube, or angle, whatever you have available. Get it pulled flat, weld on the strongbacks, then weld or bolt the assembly to your frame?
Reply:And if that doesn't workDo as Sundown suggests and backbead it. But do it in a solid unbroken weld exactly on the peak of the bend. And do it with pressure on the plate like you have in your pic. 6013 works best for this because it's easier to grind off. It might take quite a few passes.Your weld will be across the short distance, not the long distance. IE, the 2 instead of the 4Rock a straightedge on the crown to determine the exact peak. Then mark it with soapstone and have at it.If you're seeing no movement you could put a bevel in the plate(not all the way through) and weld it. Lottsa shrinkage there"Any day above ground is a good day"http://www.farmersamm.com/
Reply:do like farmersamm said. clamp it and weld it on. It will be fine.By the way metal will move more if you allow it cool slowly.
Reply:Kaiser......my post #16 wasn't related to your suggestion, it related to my post #14 The "if that doesn't work" sentence"Any day above ground is a good day"http://www.farmersamm.com/
Reply:farmersamm my post related to your #14 although your next one would work to
Reply:By now, he's thrown his hands up in disgust And has made a solemn vow not to ever present a question on this board again"Any day above ground is a good day"http://www.farmersamm.com/
Reply:Most welding tables i've been around end up getting bent, mangled, and warped anyway. You just have a headstart on the bent part.
Reply:wrap a chain around it and use a 20ton bottle jack?-NateMiller Trailblazer 302gMiller Spoolmatic 30aLN-25 x 2Idealarc SP200Hypertherm Powermax 600
Reply:............. Attached Images"Any day above ground is a good day"http://www.farmersamm.com/
Reply:Originally Posted by kaiser715Rather than welding it to the 11ga (haha) and getting it to hold w/o warping up the frame, how about a heavy strongback? Maybe 2 or three down the length...like 1/2x3 flatbar on edge, some heavy square tube, or angle, whatever you have available. Get it pulled flat, weld on the strongbacks, then weld or bolt the assembly to your frame?
Reply:Avast there!!!!!!!!!!!!We're tryin' to preserve the delicate architectural lines of the original frame"Any day above ground is a good day"http://www.farmersamm.com/I can see this really gettin' outta hand here Attached Images"Any day above ground is a good day"http://www.farmersamm.com/
Reply:Originally Posted by farmersammAvast there!!!!!!!!!!!!We're tryin' to preserve the delicate architectural lines of the original frame
Reply:New member here, hope it's OK to just jump in. Welding short beads will work, too much work for me I'd use a torch. Attached Images
Reply:Howdy CEPI wonder if the beads would have more pull if they were run the other way, parallel to the plate's long edge?
Reply:Thanks to everyone for all your advice! I'll get back to the table sometime this week.Farmersamm,Funny thing is.......I actually have some bright yellow paint.However, I was thinking of something a little more subdued. I don't want to get flashed from the bright paint every time I look at the table.
Reply:Originally Posted by joedirt1966. . .Farmersamm,Funny thing is.......I actually have some bright yellow paint.However, I was thinking of something a little more subdued. I don't want to get flashed from the bright paint every time I look at the table.
Reply:Speaking of flashed..........I would like the number of Farmersamm's painting woman..........he had to let her go because she was wasting paint.I think I have a job that she can handle.
Reply:Originally Posted by denrepHowdy CEPI wonder if the beads would have more pull if they were run the other way, parallel to the plate's long edge?
Reply:I'll second or third, or what ever we're up to now the strong-back idea. We used 1/4 < to do this to a plate like yours. Found the skip weld/torch to put in heat to unevenly. Or..... put a level on the concave side and mark where the bend is. ( Is it bent in the middle or through the whole length ?) Cut 1/8" kerfs on the convex side. Use c-clamps to squish ends down. Kerfs will let the 1/2" plate act like thinner plate. Weld it to your frame, or to a strong-back first, then stitch up the kerfs. Paint it yellow but, add black Zebra stripes, cause that's what Ted Nugget would do!!!!Best luck.Bert200amp Air Liquide MIG, Hypertherm Plasma, Harris torches, Optrel helmet, Makita angle grinders, Pre-China Delta chop saw and belt sander, Miller leathers, shop made jigs etc, North- welders backpack.
Reply:WE WANT A PROGRESS REPORT!!!!!!"Any day above ground is a good day"http://www.farmersamm.com/
Reply:I won't get another chance to work on table until tomorrow. Update to come.Thanks,
Reply:Had about 30 minutes free time Tuesday evening. Decided to put the plate under the center of the front axel of my truck, place a scissor jack in the center of the plate (convex curve up) with 2x4 blocks at each end of the plate. I jacked the entire front end of my truck up into the air (full weight on plate) and achieved an approximate 3/4+" reverse bend in the plate. That ought to do it!Lowered the truck.........Sproing! $@%*&$*!!! NO CHANGE!!!My son and I gently placed the plate in the back of my truck (Wouldn't want to bend it). I figured, since I have to go to the metal yard today for some more stock, Ill take it with me and see if they have a straighter plate to trade/exchange for. Im having a huge mental aversion to spending a whole day running stringers and grinding in attempts to get the plate flatter. Seems like a terrible return on my initial $90.00 investment to spend hours upon hours welding and grinding to get the dang thing straight.Again, much appreciation for everyones input.
Reply:If I were closer I'd loan you my mother in law to stand on it while you tacked it in place.Lincoln PowerMig 180cVictor O/ABandaids and aspirinI don't know what I don't know!?
Reply:Old School Fitter = Maul (16 lb sledge)Even today, a fitters primary tools are:Tape measureSoap stoneMaulExperienceMy first two years were spent as a Fitter/Welder before breaking out, We built ships. The ring of the Maul meant hours upon hours of follow up work for welders.
Reply:Originally Posted by joedirt1966I recently purchased a 2'x4'x1/2" plate for a small welding table. I didn't notice that the plate had an approximate 1/4"-3/8" bow in it longitudinally. I need this plate much closer to flat before I weld it to the table since the frame is only 2" x 11 guage. I've tried 3 methods to straighten it without avail.(snip)Method 2: Heated the plate on the convex side with a propane weed burner for 5-10 minutes then doused it with water until cool. *@#$&* No ChangeMethod 3 (see pictures): Mounted it on a scissor table with 4"x6" wood above and below then pulled each side down with a 2 ton cable puller (come along) on each side. The plate would reverse bend approximately 1/4". I didn't try to pull it more because the eyelets started to open under the force (see picture). Sproing......right back to the original reverse bend.I wasn't sure if running stringers on the top of the curve would reverse the bend of 1/2" plate. In addition, I didn't want to waste any more time today grinding them down if it didn't.Question 1: Does anyone think the "come alongs" will work if chains are used around the 4"x6" wood instead of the eye bolts? My best option may be to speak with my supplier and see if an exchange is possible (Two 1/4" plates since they will be easier to flatten??).Any opinions?Thanks in advance.
Reply:If you decide to use chain to tension the piece....The 20' tow chain at lowes is 5/16" grade 70 transport chain - working load of 4700lbs for only $39 including 2 binder hooks. I use these chains as tiedowns for equipment and for heavy tree work. Hard to beat that price - you can never have enough chain.
Reply:Originally Posted by gwileyIf you decide to use chain to tension the piece....The 20' tow chain at lowes is 5/16" grade 70 transport chain - working load of 4700lbs for only $39 including 2 binder hooks. I use these chains as tiedowns for equipment and for heavy tree work. Hard to beat that price - you can never have enough chain.
Reply:I may be too cautious, but --I wouldn't ever do anything like that with a lightweight (1 ton) come-along. I immediately imagine the pictures on the internet of the emergency room visit after some piece let go and all of that force shoots metal fragments out in random directions.If I used a chain and a bottle jack, I'd want the chain to be ridiculously over-rated (see above). I don't know what the forces involved in bending a piece of steel that thick are like, but consider the fact that your very heavy truck didn't do much to it. It might not send the chain out at speed, but a suddenly un-flexing piece of steel that big is going to be a mean-spirited dancing partner.Do you know anyone with an Oxy-Acetylene setup? Do you have some decent drop-forged 6-, 8-, or 10-inch c-clamps? It might be cost effective to go out and buy a straight piece of steel and find another use for this one.Jack OlsenMy garage website
Reply:As mentioned in the post above, the steel supplier I purchase from found a straighter piece and exchanged the bowed one.
Reply:Table top is on and straight. The casters are on backorder for 3 weeks. The ends were left open for attachments (vice, ring roller, etc.). Once the wheels are on, i'll paint it and repost.Thanks again for everyones advice!The second picture is probably uncalled for! I just wanted to show off my 24" Johnson. Attached Images
Reply:Thats great that they exchanged the top for you
Reply:That's a fine looking table! Congrat's!200amp Air Liquide MIG, Hypertherm Plasma, Harris torches, Optrel helmet, Makita angle grinders, Pre-China Delta chop saw and belt sander, Miller leathers, shop made jigs etc, North- welders backpack.
Reply:Looks great, enjoy,Last edited by kolot; 05-30-2010 at 09:08 AM."Si Vis Pacem Para Bellum"Lincoln Idealarc 250 AC/DCMillermatic 251 Syncrowave 300 30A spoolgunLincoln MP210Hypertherm 45(2) LN 25(2) Lincoln Weldanpower 225 CV(4) SA200 1 short hood SA250 SAM 400
Reply:Hey!!!! It turned out nice "Any day above ground is a good day"http://www.farmersamm.com/
Reply:Take the eleven gauge and make a go cart for the nieghbor kids.That will get you some welding experience. Then go aquire some heavy iron and build a real table so you can make that 1/2 plate do what YOU want.Besides if you are getting serious abuot welding those little legs will bend sooner than you think.My latest table is an 8'x12' flat bed from an oilfield truck,1/2 plate on most of the top,4 ton crane in the corner.Rail road tie cribbing for legs.Its sort of adequeteoops! I should have read all of page two before I posted this.My bad!That is a good looking and well built table!I am embarrassed and am going to go hide in the cornerLast edited by 1-800miner; 06-01-2010 at 12:25 AM.tractor,loader.dozer,backhoe,and all the tools to keep em movin |
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