Noob with an advice question on design

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Hi everyone,Well, since I just introduced myself, hopefully it's soon enough to ask for some advice, here goes ....Being that I am new to welding and have been practicing with my MM210 for awhile now, I thought what better way to learn and get my feet wet than to find something pretty basic to build for someone else, good idea or not??Here is the question - I found a couple who needs a stand built for a 240 gallon aquarium, 24"x24"x96".  As far as design goes, it needs to be between 36 - 48" off the floor and have a shelf, sounds pretty basic?Calculation wise I figure with the tank 75% full of water and the weight of the tank, it will be around 2,000 #'s or so.  It will have 8 0r 9 turtles in it, so not exactly a typical fresh or salt water tank ....My design ideas so far ....2" Square tubing, 1/8" wallBuild a 24 x 96" frame w/ cross members (2) every 2 ft.6 Legs, Leg length at 36", 80 degree angle, gussetted on both sides of legsLower shelf 12" above floor w/ single cross member between middle legsFor feet, either some round plates or tube ends with adjustable feet for leveling purposesAny and all ideas and advice on this design are truly appreciated.  I don't want my first welding job to be one of my last if it doesn't hold.  Thanks,Tom
Reply:I don't think I would test the waters with an aquarium stand, if it fails they are out a few $1000 plus water damage structural damage (on a second floor or if they have a basement) and loss of animal life.
Reply:Well, that has been a consideration for sure and while I am new to this, I do have a certified aircraft welder/fabricator who builds race cars and custom cycle parts as well, right across the street for some help.  This is on a main floor above a basement which is a concern also, for them as well as the stand. Hence the reason I posted this request for advice.  I certainly don't want to go into this unprepared for sure, and if deemed necessary I will pass on this one.Thanks for the input!
Reply:I am no engineer, but 2" 1/8" wall seems reasonable, 3/16 would be better in my opinion.  How much does a turtle weigh?  As far as your skills, I have no idea.  Design sounds reasonable too. 96"  is a long run, perhaps 6 legs to distribute the weight better.  With 4 legs, you are putting 1,000 lbs on one floor joist.MY opinionDavid  Real world weldin.  When I grow up I want to be a tig weldor.
Reply:That weight over that area exceeds most residential floor load design criteria.  The floor will most likely need beefing up as well.  Unless it's going onto a concrete slab on-grade (basement floor?).  Also watch out for point loading (imprint denting) of the feet/legs onto the floor.Find out what the support requirements are for underneath the tank bottom/floor.  That will help figure out the platform design.Glass is -most- unforgiving of bending.  Make sure the top of the stand is flat and level for the tank to sit on.I think your legs need to be beefier to handle side loads of all that weight.  Sloshing and racking would be not good.Hmmm, 1/8 inch wall tube?  I'd go at least a little thicker, to 3/16 or 1/4 inch wall if you want to stay with the 2x2 tube.  If you go to 3x3x1/8 tube, you get a little bit more strength:weight ratio and a little stiffer side-to-side structure.  Note, the 2x2x1/8 tube is strong enough in straight compression, it's the side loads and buckling (when an axially loaded column bends) that could do it in.
Reply:If you have a pro welder that can help you out then I see no reason not to. If possible weld feet onto each leg say 3x3" square to help the load or 2.5" diameter circles. either 6 or 8 legs is a must, and use some type of foam or soft rubber on the surface that contacts the actual tank to help it sit flush and prevent stress fractures. On the back and sides make sure you add X crossing support so you don't cause weld failure from bending.
Reply:Thanks for the help and input, I appreciate it.  I will have to check the possibility of them placing this tank in their basement.  In addition to this 240 Gallon tank, they will also have a 125 Gallon tank too.Beefing up the size of the tube is not a problem at all, both in wall thickness and dimension. As far as design requirements from the owners, there really aren't any specific requests other than support.
Reply:I was initially thinking 6 legs with some sort of pad on the bottom as well.  I have a ready supply of conveyor belting, any thoughts on that as a pad??
Reply:Originally Posted by Magnus ForgeI was initially thinking 6 legs with some sort of pad on the bottom as well.  I have a ready supply of conveyor belting, any thoughts on that as a pad??
Reply:Originally Posted by SandyI'd think the more layers of that sort of thing=the more wobbly it's going to be.  The floor overlay is going to dictate whether you go with 4 legs, 6 legs, 20 legs or a ring base. What's supporting the floor will dictate whether they want to go with that kind of load in that space or not. Support beams, joist locations and such. A heavy load in one spot for an extended period could lead to some serious sag. It's all about pounds per sqaure inch.
Reply:I checked with an engineer before installing a water bed over a basement with one support pole removed. He advised me that houses are way over designed purposely because if you had the room full of people there is the possibility of a tremendous load per square foot. I know a water bed has a much wider footprint but you could build the base as a frame instead of legs to help spread the load and prevent imprinting. If the tank is against a wall you could maybe incorporate some fastener to the wall to help support and prevent sway. Also the floor should be somewhat stronger near a wall due to bearing point of joist.SA200,Ranger8,Trailblazer251NT,MM250,Dayton225AC,T  D-XL75,SpoolMate3545SGA100C,HF-15-1  RFCS-14 When I stick it, it stays stuck!
Reply:all good points that have been noted so far... a few things that i havn't seen yet (or i missed)...1.) look at trying to tri-angulate the frame, or at least throw on some gussets at the joints... triangles are stronger than squares... imagine if a small child (not that this ever happens...  ) was running thru the house and ran into the tank... extreame lateral forces are not good for a frame with square openings.2.) as far as feet, the bigger you can make them the better... to spread the load over a larger area... think of snowshoes. if you step in the snow without them, you sink fast... with them, you dissipate the load over a larger area and you walk on top.3.) try to make the legs adjustable... if they decide to move the tank later, say to a place where some feet will be on the carpet and the others on a hard laminate floor, there will be a height difference and this will need to be accomadated for4.) we use 2" tube (7 ga) a work for discharge pipe supports... that stuff is holding up about 300 pounds a piece (2 posts) max, but it doesn't go anywhere... i would agree that you may want to upgrade to a slightly larger wall thickness for your application. if it's a little over-enginered, oh well... it's better to be safe than sorry. also, it will make a difference on the material that the tubes are made of... SS is different that hot formed, and aluminum is way too weak for that little material holding up that much weight.5.) under the tank, lay a sheet of plywood or something... the wood will be a little more forgiving than the stong metal for supporting the bottom of the tank. the sides arn't holding a lot of weight... the majority of the weight is concentarted in the middle of a water tank. when it is only supported on the sides, it puts a HUGE stress on the joint between teh bottom and the sides.6.) how do you plan on finishing this? obviously with a large tank of water, it is safe to assume that the immediate environment will be highly humidified. i woudl look into a good, durable, waterPROOF (not water resistant) paint and primer combo. it;s suck if they needed to touch it up later when it starts to rust a little... remember EVERYTHING that goes out of your shop has your name on it. even the paint jobs on your work.just my $.50 cents.Later,Andy
Reply:Most professional (manufactured) aquarium stands use wood and have a base that is basically 2 inches wide and around the entire perimeter of the aquarium. Triangle gussets add a lot of strength and IMHO look pretty nice too.
Reply:I bought a 60 gallon tank many years ago and was shocked to discover the 'wooden' stand that came with it was actually particle board.  That had to go before I set up the aquarium.  I built a frame out of 4x4 lumber, two rectangular rings, with a separate 4x4 rectangular ring around the bottom.  Vertical supports with levelling screws were placed between the frame and the bottom ring.  The idea was that the bottom ring would spread the load evenly on the floor, while the levelling screws kept the tank level.  The entire thing was enclosed with panelling, hinged doors, etc.  It was heavy!  People that tried to move it thought it was bolted to the floor.I think you could do something similar with steel.  That is, a complete top & bottom frame mounted on a separate levelling ring.  When the tank is placed on the stand, you need to level it before filling it completely.  Do this by putting just a few inches of water in it and measure the level at the four corners of the tank.  The top of the stand that contacts the tank needs to be flat & smooth, then it needs a firm cushion.  You need cushioning that isn't too thick or mushy.  I think a pliable plastic material would be best; nylon, etc.Last edited by steve45; 11-17-2007 at 09:56 AM.America Needs AMERICA'S Oil!!!"Global warming is the greatest scam in history ...There is no run away climate change. The impact of humans on climate is not catastrophic. Our planet is not in peril."--John Coleman, Founder of The Weather Channel
Reply:Hey everyone,Thanks a bunch for all of the input and ideas.  I have a call into the owners to get some particulars on the space they have designated for the tank in relation to floor joists, any possible bearing walls below in the basement, etc...After everyone's suggestions, what about a box frame perhaps 2 - 4 inches longer and wider than the tank or a pyramid style box frame, still wider and longer than the tank.  The thought there is to spread the load with the base as well.  However, it does do away with the feet idea??Also, I was thinking that if a rectangle box frame with dimensions say 102" Wide x 30" deep x 30" tall, 2.5 - 3" square tubing, 3/16" wall.  Both horizontal cross members and vertical cross members providing a center shelf, than that way could attach some doors if they so desired?What do you think?Thanks again everybody, truly appreciate all the help.
Reply:Originally Posted by Magnus ForgeThanks again everybody, truly appreciate all the help.
Reply:Ofcourse!  I'll have to get the approval from the board as I progress thru!
Reply:Originally Posted by Magnus ForgeOfcourse!  I'll have to get the approval from the board as I progress thru!
Reply:Personally I wouldn't make it much bigger than the aquarium, most stands only protrude about .5-1" in any given horizontal dimensions from the aquarium, you could flare it out towards the bottom, I have a 30 gallon that has a cast iron stand that is simply bent rod about 1/4  -   3/8"  and pressed into slots that are welded onto a bent rod horizontal frame. the pressure points are about .125 or less square inches, sitting on completely crushed carpet on a cement slab.
Reply:Originally Posted by Magnus ForgeHi everyone,Well, since I just introduced myself, hopefully it's soon enough to ask for some advice, here goes ....Being that I am new to welding and have been practicing with my MM210 for awhile now, I thought what better way to learn and get my feet wet than to find something pretty basic to build for someone else, good idea or not??Here is the question - I found a couple who needs a stand built for a 240 gallon aquarium, 24"x24"x96".  As far as design goes, it needs to be between 36 - 48" off the floor and have a shelf, sounds pretty basic?Calculation wise I figure with the tank 75% full of water and the weight of the tank, it will be around 2,000 #'s or so.  It will have 8 0r 9 turtles in it, so not exactly a typical fresh or salt water tank ....My design ideas so far ....2" Square tubing, 1/8" wallBuild a 24 x 96" frame w/ cross members (2) every 2 ft.6 Legs, Leg length at 36", 80 degree angle, gussetted on both sides of legsLower shelf 12" above floor w/ single cross member between middle legsFor feet, either some round plates or tube ends with adjustable feet for leveling purposesAny and all ideas and advice on this design are truly appreciated.  I don't want my first welding job to be one of my last if it doesn't hold.  Thanks,Tom
Reply:Rojodiablo,I appreciate the help on this.  Should I make the base frame wider than the top frame or will it be ok with the same dimensions on top and bottom as long as the vertical and horizontal supports are there, considering my plan to make the overall height of the frame only 30" ??That boat frame looks kinda like I picture this frame in a way, a rectangle box with vertical supports every 2' and a middle shelf somewhere between 12-14" from the bottom.Great looking boat mold, look forward to seeing more pics!Thanks,Tom
Reply:what you are purposing is more than adequate.
Reply:Sounds good, just waiting on an approval from the owners on the design and materials as well as additional input on the possibility of adding doors?
Reply:Don't forget to check if the location for installation is level - another reason for the adjustability that aczeller mentioned. A floor that is off a fraction of an inch will make your work look bad, since everyone will notice the water level across the tank.  When you are done, load it up with sac crete bags, etc, to test it out before the tank.  Try to be the excited 10 year old and push on it sideways a lot.....  Good luck, sounds like a fun project!
Reply:Originally Posted by Magnus ForgeSounds good, just waiting on an approval from the owners on the design and materials as well as additional input on the possibility of adding doors?Well, as for the latest progress on this project, there isn't any!  The owner has changed her mind and going another direction for this stand.  After purchasing the tanks for the turtles, the budget for stands (240 & 125 Gallon) is pretty minimal at this point.Thanks again for all of the help and advice that everyone contributed for this project idea.  I'm sure I will have other projects that require help and advice and I look forward to discussing them as they come up.Happy Thanksgiving to all,Tom