How much weight can this piece of steel take

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I plan on building a part out of 1/4 " plate.  Essentially, there will be a 1.5 - 2 " long piece (2" wide) sticking out from my table, with a bolt in it, holding on to a 2 x 2 " piece (I would draw it up if I were at home).  The first piece will be welded to the table.  The second will be bolted to the first (maybe 1/2 from the edge, witha 1/2" hole), and will be allowed to swivel.Essentially, when I need to support a water table I will swivel the piece under the table.  When I need to remove the water table, I will pick up the tray and swivel this piece away.... allowing me to drop the table.As I will have water in the water table, and don't want to bend the piece, I wonder if it is enough (with a small gusset under the first piece welded to the table)Thanks in advance.The Lord has declared, "This is my work and my glory--to bring to pass the immortality and eternal life of man"  Moses 1:39Link: My name is John, and I am a member of The Church of Jesus Christ of Latter-Day Saints.-- ColdCreekWorks.com --
Reply:I think that we would need a drawing of some kind to give you good advice.   Not sure what I am imagining is what you are imagining.   Also, how much does the water table weigh?  How many gallons or cubic feet?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:I came home from work and drew it upThe triangle piece will be bent down at 90 degrees and welded. Attached ImagesThe Lord has declared, "This is my work and my glory--to bring to pass the immortality and eternal life of man"  Moses 1:39Link: My name is John, and I am a member of The Church of Jesus Christ of Latter-Day Saints.-- ColdCreekWorks.com --
Reply:Taking another look at this, I will have to make the smaller piece about an inch longer than it is shown in the pic.The table is roughly 2.5 x 4.5 feet and 4 inches deep.  It weighs around 100 lbs I think.  One side is hinged (at least the part that holds the tray), so 1/2 of the weight is supported easily by that side.  I would have two of these, one on each side, of the non-hinged side.The Lord has declared, "This is my work and my glory--to bring to pass the immortality and eternal life of man"  Moses 1:39Link: My name is John, and I am a member of The Church of Jesus Christ of Latter-Day Saints.-- ColdCreekWorks.com --
Reply:My calculations suggest that 1/4 inch by 2 is way too small.   I assumed a 100 pound load cantilevered out 2 feet. Formula for Z = b*d*d/6.   2 x .25 x .25 /6  = 0.02 inches cubed (section Modulus for 2 inch by 1/4, bending on 1/4 thickness)Cantilever stress is W * L / Z.   = 100 pounds * 24 inches / .02 inches cubed = 120,000 psi, about 10 times too high.   (I was taught in the steel mill to design to 12000 pounds per square inch of stress, to provide a good safety factor.   And welds were derated to 8000 psi stress, as the quality was more questionable).These were quick calculations, but it looks like you are not close to having something that would work.  Even going to 2 inch by 0.5 inch is not enough.    3/4 inch thick might work, however.That is a pretty big table, and cantilevering it is not trivial.   You might want to rethink your design.  Maybe you could put the whole thing on casters, or design a more complex support.   The friction is another issue, even if it would stand the weight, the friction might prevent it from working freely.I would do a complete rethink, and design something with more than a single bolt pivot, maybe a top and bottom bearing.Good luck,RichardRichardSculptures in copper and other metalshttp://www.fergusonsculpture.comSyncrowave 200 Millermatic 211Readywelder spoolgunHypertherm 600 plasma cutterThermal Arc GMS300 Victor OA torchHomemade Blacksmith propane forge
Reply:Originally Posted by rafergusonMy calculations suggest that 1/4 inch by 2 is way too small.   I assumed a 100 pound load cantilevered out 2 feet. Formula for Z = b*d*d/6.   2 x .25 x .25 /6  = 0.02 inches cubed (section Modulus for 2 inch by 1/4, bending on 1/4 thickness)Cantilever stress is W * L / Z.   = 100 pounds * 24 inches / .02 inches cubed = 120,000 psi, about 10 times too high.   (I was taught in the steel mill to design to 12000 pounds per square inch of stress, to provide a good safety factor.   And welds were derated to 8000 psi stress, as the quality was more questionable).These were quick calculations, but it looks like you are not close to having something that would work.  Even going to 2 inch by 0.5 inch is not enough.    3/4 inch thick might work, however.That is a pretty big table, and cantilevering it is not trivial.   You might want to rethink your design.  Maybe you could put the whole thing on casters, or design a more complex support.   The friction is another issue, even if it would stand the weight, the friction might prevent it from working freely.I would do a complete rethink, and design something with more than a single bolt pivot, maybe a top and bottom bearing.Good luck,RichardRichard
Reply:Alright, I decided to try it out anyway.... I figured if it didn't hold I could always cut it out and redo it.I estimate that with water the tray weighs in at about 300 lbs.  I added the parts as described and climbed on the table.  Didn't even flex and felt really solid.  Filled the tray with water, and is still solid.  I don't see any deflection in the steel whatsoever.....So the short answer is that it held it without any issue.Thanks to everyone for their replies, I appreciate them.The Lord has declared, "This is my work and my glory--to bring to pass the immortality and eternal life of man"  Moses 1:39Link: My name is John, and I am a member of The Church of Jesus Christ of Latter-Day Saints.-- ColdCreekWorks.com --
Reply:Could you please post a photo of your FINISHED project?  Thanks!It is very frustrating trying to help and think about your project with out ANY photos.AWS certified welding inspectorAWS certified welder
Reply:Camera died, but I will see what I can doThe Lord has declared, "This is my work and my glory--to bring to pass the immortality and eternal life of man"  Moses 1:39Link: My name is John, and I am a member of The Church of Jesus Christ of Latter-Day Saints.-- ColdCreekWorks.com --