Hey guys, Anyone know of a good load calculating site? I've been contracted to build two bases for two 250 gallon salt water aquariums. 72" x 24" x 40". I quoted the gig using 1/4" wall 2" square tube. The customer wants me to lighten it. I 'm sure 1/8" wall would handle it but would like a resource where I could run the numbers. Thanks for all information.Miller TrailBlazer 251Miller HF-250-1Miller MaxStar 150 STLHyperTherm PowerMax 380 plasmaLincoln PowerMig 180Millermatic 252Miller Diversion 180
Reply:I'm not sure if Engineering Toolbox has it but there's a 90% chance they do, http://www.engineeringtoolbox.com.I've used their site a few times when I was stuck on something my hard pushing professors gave for an assignment. So far from high level physics to dynamics/statics I could find some help.Good luck.
Reply:250 gallon fish tank?That's -over- a ton of water. Add salt, rocks, fish, glass of the tank itself, and so forth and that is a bit more weight.And the customer is somehow 'worried' over the maybe 'extra' 100 pounds or so of steel by using 1/4 inch wall square tube versus 1/8 inch wall square tube?Add in that glass doesn't flex much before it turns into glass PIECES, and you pretty much really-really-really want the frame/stand to be strong enough and STIFF enough to support the weight and support the tank without flexing/deforming/sagging.yes, at an assumed equal load sharing of the weight over 4 leg posts made of 2 inch square 1/8 inch wall steel tubing, the plain compressive stress in the posts is pretty darn low. 2400 lb / 4 posts / (2^2 - 1.75^2) in^2 = 640 psiBut that is just the posts in plain compression.The 'rails' have to support the weight without bending/sagging so that the glass tank panels don't crack.And the entire structure has to be strong enough and stiff enough and stable enough to handle side-loads and 'sloshing'. The best laid schemes ... Gang oft agley ...
Reply:Wagin, you might look at this thread for some info. Almost exactly what you might need. Jinkzd was also working on a few other stands besides that one. Can't remember if I discussed them with him by PM or if it was in another thread.http://weldingweb.com/vbb/showthread.php?t=36668Important info from that thread... Originally Posted by AquafireOne thing about making aquarium stands (and I'm sure Jinkzd's wife made sure he knew this) is that they have to be perfectly flat throughout. Any slight raise in one area can cause stress on the glass and the silicone joints- which sooner or later (usually later, when you're away from home on vacation) the tank starts to leak....
Reply:Check what lighter gauge material and a Truss can do these are Stage Deckshttp://www.steeldeck.com/assets/dl/T...IR_5-25-08.pdfhttp://www.steeldeck.com/assets/dl/s...tions_1207.pdfhttp://www.steeldeck.com/index.htmEd Conleyhttp://www.screamingbroccoli.com/MM252MM211 (Sold)Passport Plus & Spool gunLincoln SP135 Plus- (Gone to a good home)Klutch 120v Plasma cutterSO 2020 benderBeer in the fridge
Reply:Might also want to know where it is going, fine on a commercial concrete slab, but on a loft or wooden apartment floor with say 1/2 inch plywood subfloor could also be a problem, not your problem, but might want to ask."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:Originally Posted by MoonRise250 gallon fish tank?. 2400 lb / 4 posts / (2^2 - 1.75^2) in^2 = 640 psiBut that is just the posts in plain compression.The 'rails' have to support the weight without bending/sagging so that the glass tank panels don't crack.And the entire structure has to be strong enough and stiff enough and stable enough to handle side-loads and 'sloshing'.
Reply:I assume the stand is going to sit on the floor and not be subject to any need to carry it around, once it gets to wherever it's going. With that in mind, who cares how much the thing weighs?? Build it strong and don't worry about weight. I've had customers that worry about how heavy something is that's going to spend it's entire life sitting on the ground, or even concreted into the ground. I say, 'who cares? You're not carrying it around, the ground is doing all the work, don't worry about weight.' I'd rather something be heavy and strong, than too light and fall down and hurt somebody.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
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ike I mentioned in my earlier post, and like DesertRider33 also said, who cares about the weight of the stand? It's not going to be raced, it doesn't have to fly, and you don't have to carry it around with you. So what if it is an extra 100 pounds heavier than an engineered space-frame truss system made of honey-comb thin-gauge extruded aluminum!Just in the water alone, there is about a full TON of weight right there. So what if there is 100 pounds 'extra' of steel in the frame.And about a +24 on the structure of the building/space itself that is going to hold that big tank up. On a concrete basement or garage floor on-grade, pretty much no problem. On a wooden floor somewhere in a house or even lighter-rated commercial building, BIG problem!Even if evenly distributed across the entire footprint of the tank area of 6 ft x 2 ft and not just on 4 or 6 posts, that weight gives a floor loading of about 200 lb/ft22400 lb / (6 ft x 2 ft) = 200 lb/ft2Which is waaaaay over what a 'typical' floor is designed and made to carry.It -can- be done, but not just by plopping that big monster tank onto a 'regular' floor.And as I also mentined in my earlier post, it's not really the strength of the posts as even 1/8 inch wall 2 inch square tube is plenty 'strong' for the posts, but rather the rails and sagging and side-loads and sloshing and such.Last edited by MoonRise; 12-01-2010 at 11:02 AM. The best laid schemes ... Gang oft agley ...
Reply:If the customer wants to specify the steel and the weight of the stand then they should design it also.
Reply:As I sit here typing this, there is a 1000 liter tank to my left. Not full and I intend to get rid of it. It's a big MF'er. The frame it's on is 2x6 on edge with a 3/4 plywood top. 2x4 braces across this frame and doubled 2x4 legs. It came with the house. Any one want it? The floor is plywood and trusses and was spec'd to hold this load. My first gut response, if your client just wants it built "lighter" to save some money, then run, not walk, away. The client is out of there depth and shouldn't be acquiring such a set up. If they are worried about the load on the floor, please see above. If they are just being a design poof, then tell them chunky legs are the new couture according to Lagerfeld. Meaty, baby, MEATY! If you want to spread the weight out more than just on the contact points of the 4 or 6 legs, weld the same square tube across at the feet. This will at least allow the weight to straddle the floor joists( if a framed floor is the case here) And as everyone else has said, cross bracing is where your insurance is You could probably use 1" x 1/8" square if your brace/trussing is good. Glass+ possible dynamic load= $hit sandwich!!!!Also a rubber gasket for the bottom edge of the tank to sit on will go a long way in relieving small stress points.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:Thanks for all the info.... I went with my "gut" and given advice. I quoted the job using 1/4" wall tubing. The tanks are to be recessed and wood finished into the walls, each side of the fire place. Maybe way over eng... But I won't have to worry. Thanks guys.Miller TrailBlazer 251Miller HF-250-1Miller MaxStar 150 STLHyperTherm PowerMax 380 plasmaLincoln PowerMig 180Millermatic 252Miller Diversion 180