Why DIY Stands Fail

[Big Daves Rays]

I have been building houses for 7 1/2 years. Here is a few pics of the stands I built for my 2 450 gal. treated 4x6's around the edges with 4x4 legs at the corners and 2 in the middle of the side that has the 2x6's hangered on the 4x6. Through the middle is a double 2x6 with another double 2x6 leg in the center of the stand. 4" deck screws everywhere. Each leg has 2 3x4 angle braces. The 2x6's are every 12" on center. The top plywood is 3/4 plywood with 1 3/4 deck screws about every 6"

One thing I notice about alot of stands that really bugs me is the use of OSB plywood, particle board or that MDF plywood. If Water gets spilled on that, it starts swelling and soon your stand is crap. Even the nice ones you buy at your LFS for hundreds of dollars use it and I can't figure out why? I have made many stands for myself and friends and I always use real plywood. 1/2 on the sides and 3/4 on the tops. On the inside of the stands I always put a clear coat on just in case you get some water spillage. Another thing to remember, if you use that new treated wood, use the deck screws with the protective coating on it. Thats what I use for screwing all my stands together.

 

[Big Daves Rays]

pics didn't upload. I'll try again.....

 

[IITUFFTOBEATII]

This is an interesting discussion, I wish I was around when it started.....

There is a few comments I would like to make just as food for thought.

Concerning lateral support most of the points here are valid, but this only provides for local lateral support. Meaning that your stand will resist the applied force of your fat friends leaning on it etc etc, but thats as far as it will go.

I can say with 100% certaintly that there is not a single person here that has an aquarium/stand that is earthquake proof. The reason I can say that is that there are only a handful of structures in the world that are earthquake proof, and only two that I know of in the US that are meant to be occupied, (The W hotel in San Francisco, and the Plaze Lofts in downtown sacramento). Even if you live in a so called earthquale proof structure that does not mean that your aquarium is earthquake proof unless that structure was designed with your tank in mind. By the way, the designer did not have your tank in mind.


Most people are familiar with the idea of a ground in electrical work; but most people fail to see that the same applies to physical loading. In order for a system to remain static (not moving) all forces must be transfered to the ground. When your friend leans on your tank the stand resists the lateral force through the frame and the load is ultimately distributed to the ground vertically there is also some horizontal resitance through friction with the floor. It is a much different phenomenon when a seismic event occurs, unless your stand is secured to a system that will resist significant horizontal forces and that will distribute the the forces to the foundation you are not earthquake resistant. This is assuming also that your tank and stand act as a single unit, which is almost never the case.

I do live in the so called "jiggly" part of the country, and seismic design is a regular part of my life. I am still EIT, and just started working as a project engineer so I'm a few years off of getting my PE. However the company that I work for designed and built the Plaza Lofts so I have seen a lot of privelaged information about lateral force resisting frames.

I'd be curious to know if there are any members here who had aquariums set up during the Loma Prieta or Northridge earthquakes, (and also obviuosly lived in the effected area) and how they fared

 

[amazonfishman]

No diagonal bracing here either, 240 gallon stand thats 40" tall built with 4x4 legs and length and depth reinforcement with 2x4's top and bottom and then finished in 3/4" oak 4x8 sheets for exterior reinforcement and bling The freaking stand weighs around 200-250lbs rough guestimate based on my friend and I lifting it, its a heavy mother ~Trent

 

[fish head )'>]

pics didn't upload. I'll try again.....

All the weight of the aquarium is concentrated on the legs to the floor at 4x4 points. SUGGESTION: Spread out the weight by building a base. Image if those legs are not perfectly over a floor joist and the OSB floor boards get wet! Build your house (aquarium) on a good foundation.

 

[Phixer]

It is nearly impossible to build an earthquake proof structure. Any structure will fail if subjected to enough intensity for a long enough duration. Having lived in Japan for many years I learned a great deal about structural design and methods of siesmic isolation. The costs of building such a stand could quickly exceed one of the main reasons to DIY in the first place...savings.

Of course quality of work and pride are other good reasons.

Another function of engineering design is to effetively produce a product to function within given parameters without exceeding a predetermined cost. (DIY fundamental) Most people have seen the huge rollers and polymer isolation mounts some of these buildings and structures rest upon.

Several good points made. IMO if your going to build a stand for use in a siesmic prone area there are a few areas worth mentioning.

1. Use an acrylic aquarium. Due to it's charicteristics your chances of survivability are much greater with this material.

2. Common sense, but if you can build wide your tank will be much more stable. A wider foot print is normally more stable when subjected to lateral forces.

3. Make sure its level, even a slight variation will amount to exponenetially greater loads when full. Ive heard of people using leveling cement over plywood to ensure a completely smooth and level surface before placing a sheet of foam on top.

 

[rockinthe40ounce]

they are cheaper but i still have my doubts

 

[synapse989]

ok guys.. since this is all about stands.. ..I build mine out of steel. I have photos of the one I'm using with my 90 gallon snake tank..

at one point before it was finished, I had to use *something* to hold 8, 3/4inchx10 foot I-beams. ..roughly 3/4ths of a ton each. ..do the math. I know not everyone owns the metalworking tools I do, but I will guarantee that my stands are earthquake/hurricane/fire/flood/fat friend proof. 2"x3/16ths angle iron is damn strong stuff.. with cross/lateral braces and gusseted corners I'm pretty confident that I build the strongest steel tank stands around. 1000 times stronger than that crap I keep seeing at the LFS...

over 100 hours into this particular stand.. all the detail work was hand cut and shaped. ...I have a CNC system now... wish I had it when I was building this for the leaves and stuff..

I don't know exactly how much it weighs, but it's around 75lbs.

 

[Razman]

i asked this already in my thread and i was never answered, will it hold my 40gal.?

 

[fish head )'>]

ok guys.. since this is all about stands.. ..I build mine out of steel. I have photos of the one I'm using with my 90 gallon snake tank..

Awesome! Pictures with tank and snake please!
100 hours, it would be hard to sell that at the LFS for $100 to compare with the stuff they sell.