# cabinet build for 8ft x2ft x2ft tank??



## kkjjjmccann (Mar 27, 2016)

i wanna build a cabinet for a 8ft tank much like the one posted here with the exception of a 3/4" piece of plywood running from to back top to bottom
at 3ft in from the left and 3 ft from right. so in this 2 ft center section i would have shelves or drawers and the left and right 3 foot section would be doors. i would make 3 separate floors to fit each section and a top the would extend in one piece across the top.
my thought is the 3/4" plywood at the 3 ft and 5ft area would lend additional support especially since it would be ran top to bottom.
i do not plan to use 2x4s in this build
i am considering building out of walnut and hickory

http://www.aquariacentral.com/forums/th ... ld.270233/

what are your thoughts/concerns


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## jpbdh4 (Feb 28, 2016)

Why no internal support?
With an 8 foot tank that's an awful lot of weight to support. Not saying on edge plywood can't hold it but id sleep better at night with an internal skeleton personally.
Bare minimum I'd be adding some metal l brackets/ angle iron to keep everything tied together better.
Ps I'm in construction for a living so I have a tendency to over build everything, lol. My .02


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## jpbdh4 (Feb 28, 2016)

:lol: As seen here...viewtopic.php?f=30&t=382554
But I don't loose sleep over it. Now whether or not my floor holds up is a different story.


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## GTZ (Apr 21, 2010)

Hard to visualize. Check out sketchup for planning the build, it takes a few hours to figure out but was invaluable during my stand build.


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## jpbdh4 (Feb 28, 2016)

+1 GTZ on a 'blueprint'
Sketch one up or use some software. Will help throughout the process whether it's dimensions of the pieces or just seeing the big picture.
Obviously this not what you're building but here is an example of what I quickly sketched up with my project. Not nearly as fancy as GTZ's but greatly helped with material/ sizes needed, etc.


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## SrsSarcasM (Jan 28, 2016)

Coming from someone who does woodwork on a daily basis and has built a stands/cabinets/side tables/etc, I don't understand where the structural strength is coming from in the build you linked.

Firstly 1" thick wood is not very strong, and pocket screws are one of the weakest forms of joining wood together and should never be used to hold up significant weight like a fish tank. See my favourite youtube woodsmith for videos on just how bad pocket screws are compared to any other conventional wood-joining method: http://woodgears.ca/joint_strength/pockethole.html.

Having no internal support or cross support in the middle is also very worrying especially for such a long tank.

An 8 foot tank just won't be adequately supported by 1" thick boards, and even ignoring the actual wight holding capacity of the joints and the wood itself, all of the weight of the tank will be sitting on just the 1" perimeter of the bottom of your tank. Very bad design.

I highly recommend following the tried-and-true stand template like this one and use 2x4 at least for the running lengths: http://www.reefcentral.com/forums/showthread.php?threadid=1169964

Stands like the one listed could be OK for a day, a month or a year, but do you really want to risk the cost of house damage, loss of livestock, loss of tank and equipment etc if your stand collapses, just to save a few bucks by not adequately designing it with correct internal supports?


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## jpbdh4 (Feb 28, 2016)

The link for the stand that SrsSarcasM just posted is almost exactly what I built because I didn't want the daily worry that I underbuilt it and wondering if today was going to be the day for a catastrophe. Or worse yet when you least expect it like out of town.


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## illy-d (Nov 6, 2005)

SrsSarcasM said:


> Coming from someone who does woodwork on a daily basis and has built a stands/cabinets/side tables/etc, I don't understand where the structural strength is coming from in the build you linked.
> 
> Firstly 1" thick wood is not very strong, and pocket screws are one of the weakest forms of joining wood together and should never be used to hold up significant weight like a fish tank. See my favourite youtube woodsmith for videos on just how bad pocket screws are compared to any other conventional wood-joining method: http://woodgears.ca/joint_strength/pockethole.html.


To be fair, the pocket holes are not being used to hold up the weight in the design he linked to. The weight is still being carried by the vertical wooden members - the exact same as they are in the classic 2x4 DIY designed frame. The pocket holes are only being used to fasten the frame together.

However, I'm a little concerned about the lateral rigidity in the design linked... Skinning the back of that stand in even 1/4" play would add a lot to the overall strength of the build.


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## redblufffishguy (Jul 16, 2009)

Take a look at my 40 gallon stand build I posted several years ago. The link is... viewtopic.php?t=212468

If any of you have followed any of my posts, you will know I do not believe in 2x4 construction. It is rarely necessary! The stand in my post is made from 3/4" walnut and the tank itself is held up with a 3/4" x 1-1/2" vertical member in each corner. The tank has been up and running on that stand since 2009 without any problems.

I do agree that with a tank 8' long there needs to be some internal front to back support. I disagree that pocket screws are not strong enough, unless you are not gluing and trying to use the screws for shear strength. Additionally, I have been building stands of various sizes (10 gallon to 240 gallon) for pet stores all over Northern California for more than 20 years. I have never gotten a report of a) a pocket screw failing b) 3/4" lumber failing c) any stand in general which I built using the above listed methods failing.

SrsSarcasM: 1" lumber is extremely strong. Walnut alone has a compressive strength (a board standing on end with grain running up and down) of 7,580 pounds per square inch and a bending strength of 14,600 pounds per square inch. Obviously pine is lower; however, it is still rated at Compressive: 4,460	PSI and Bend: 8,200 PSI.

If you use quality construction techniques, any 1" thick lumber used will be more than sufficient to hold the weight of the stand.

I have mentioned the following before, but here it is again: Lets assume a tank with everything inside (water, gravel, rocks, etc) weighs 1600 pounds. That tank is 72" x 18" and sits on a pine stand. The stand has the four corner legs (1" x 1") and two additional center (front and back) legs (1' x 1") touching the floor. The weight will be evenly distributed to all six legs dropping the pounds per leg to 266 pound per leg. That is assuming only the 1" legs are touching the ground.

If the stand is like most conventional stands, the entire perimeter of the stand touches the floor, which equals 1296 inches of stand touching. Lets conservatively say the vertical members are 4" wide each. That provides a total of 24" of vertical support on the stand from tank to floor. That drops the downward force to about 67 pound per square inch, no where near the failure strength of the wood.

My point is, hardwood lumber is more than strong enough for all but the largest aquariums when the construction of the stand is sound. And, having said that, who care what you build the stand with as long as you are putting an aquarium in your house!!

RBFG


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## cgimark (Oct 6, 2016)

Try to think of the weight load the same way you would if you were building a deck and figure the size of the wood needed based on the load expected. I use 8' 2x8 horizontally , 2' 2x8 every 12 inches in between and a 4x4 at each corner using a 1x4 to keep the bottom of the 4x4 legs square. Load transfers straight to floor through vertical 4x4. Notch 4x4 at top where 2x8 attach for better strength. Use bolts not nails for corners.

Very simple design with easily sources materials and you can cover it with wood however you like as main frame is independent of plywood.Leaves entire middle open to floor for whatever you want to do.


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## Pdxmonkeyboy (Oct 17, 2016)

The stand described above is WAY over built. Standard white wood (2x4) have fairly impressive compressive strength along the grain. Meaning.. all your vertical supports can be 2x4. Even your horizontal can be 2x4 if you are going to place vertical braces every 2 feet.

I just built a stand for a friend's 300 gallon monster tank. 2x4 frame with simpson braces on the corners then skinned it with 1/2" maple veneered plywood with screws 6" on center. Cover the screws with trim... done and done.


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