DIY Stands Template and Calculator

Has anyone built a tank stand from only plywood? I am trying to design an ELOS style tank but i'm no engineer! Based on some of the AGA standard tank, which are a bunch of 1x4's, it doesn't seem like I should be too worried. Of course I can't take any risk, I'm not in an apartment anymore :lmao:

I plan on going with a 2x4 plan unless I can find some good plans that have shown to be successful.

A few notes. I should be able to build an enclosed box, for the most part. The plumbing will be routed to the room behind the tank, I will have doors on the front, though (storage). Does a solid plywood back make a big difference in the structural integrity of the stand? I am plannning on using 3/4" plywood.
 
Last edited:
Logzor said:
Has anyone built a tank stand from only plywood? I am trying to design an ELOS style tank but i'm no engineer! Based on some of the AGA standard tank, which are a bunch of 1x4's, it doesn't seem like I should be too worried. Of course I can't take any risk, I'm not in an apartment anymore :lmao:

I plan on going with a 2x4 plan unless I can find some good plans that have shown to be successful.

A few notes. I should be able to build an enclosed box, for the most part. The plumbing will be routed to the room behind the tank, I will have doors on the front, though (storage). Does a solid plywood back make a big difference in the structural integrity of the stand? I am plannning on using 3/4" plywood.
Click to expand...

How large is the tank? I built one for a 75 gallon, using 3/4 birch, the stand was 36" tall (if I remember right.) Solid as a rock.
 
I wanted to follow up on a question I had earlier in the thread. I've started some of the construction of my build, which is a stand for an in-wall tank that is partially supported by the frame of the wall. Here's a quick sketch for reference.

300dd_support_stand_348133.jpg


This is designed to support a 300 gallon tank with a footprint of 72"x36". The green boards are 2x4s, the yellow boards are 2x6s, and the blue boards are 2x8s. What is not shown in the image for the purpose of clarity is that I will cover the stand in a sheet of plywood which will extend across the frame of the wall. But here's the real question;

I jointed and planed all my boards, and to get the 2x8's all completely square I ended up taking a good portion off their height. They are now precisely 6.75"x1.375", instead of 7.25"x1.5". Is this significant to the overall design? I'm inclined to think that it is not; on the contrary, I presume the precision of the boards will make it easier to level the stand and ensure proper distribution of weight, but I would like to get a few more opinions.

Secondary question; is there much value in adding horizontal crossbeams along the top of the stand? I had not planned on doing so, but in re-evaluating the sketch it may add some structural rigidity.
 
I have been trying to figure out some stuff myself. So I have been reading about beam equation. Do a search on line :). IF I understand this correctly then this affect the moment of inertia. Which determines how much deflection you will have.

If my math is correct you will have 30% more deflection, because of the smaller size. But it is still have of what a 2x6 would have been. Since the original post said you could use a 2x6 I would think you are fine.

I would add the cross beam. A mechanical engineer said it really helps. To long since he did this kind of math to say how much (hence me trying to understand the equations). I assume a glass tank. Acrylic you probably need more than one.

I am trying to figure out if I can support a 4 ft tank centered on 2x6s with just the ends supported. Any opinion?
 
Hello all.

Thanks for this extremely helpful thread. I was going to have someone build my stand, but now I'm just going to do it myself and save money. Here are my plans and items list:

Tank size: 60 gallon, 36" x 24" x 16", rimless, acrylic
Sump size: 32" x 16" x 16"
Stand size: 36" x 24" x 36"

(2) Red 2 x 4s = 36" length for upper rails
(2) Yellow 2 x 4s = 21" length for upper ends
(4) Green 2 x 4s = 34" length for screw strips
(8) Purple 2 x 4s = 29" length for uprights
(2) Orange 2 x 4s = 36" length for bottom rails
(3) Blue 2 x 4s = 21" length for bottom ends

For the sump, I will use (2) 2 x 4s = 21" length for bracing the bottom of the stand

I will be using wood glue and deck screws (2.5") to piece it together. I will also be using blue or pink foam board for the top of the stand for my acrylic tank.

Please let me know if this plan will work. Any suggestions would be appreciated. Thanks in advance!
 
crvz,
I developed a spreadsheet to do this kind of calculation for me but my desktop with MS Office on it decided to have a motherboard failure so until Monday, I am unable to check. If you can wait that long I will run the numbers at work and give you an answer Monday. I like cross pieces to keep the long boards from twisting and also giving you an easy place to mount wires and pipes.

TheFishMan65,
I know I have run equations for what you are asking but my book for doing so is currently in the office. Monday I will take a look and see what I can find.

1mbrews8,
Very nice looking stand. Keep the pictures coming.

gmr7494,
Sounds like a good plan. The only thing I noticed is that your stand is exactly the same size as your tank. You may want to consider making it even a 1/2 inch bigger. Just a thought.

Hope that helps.
RocketEngineer
 
Thanks - I look forward to your answers. If the tank can be supported in the center of the 6 foot section great. I had decided to use a 2x4 centered in the back and a 2x4 1/3 of the way acrodd the front (so I can still get a 4 foot sump in) wiht 4x4 corners as a safe design. So If A does not work, I would be interested in your opinion on plan B.

Thanks again
 
RocketEngineer said:
crvz,
I developed a spreadsheet to do this kind of calculation for me but my desktop with MS Office on it decided to have a motherboard failure so until Monday, I am unable to check. If you can wait that long I will run the numbers at work and give you an answer Monday. I like cross pieces to keep the long boards from twisting and also giving you an easy place to mount wires and pipes.
Click to expand...

I'm certainly in no rush, so if you get a chance on Monday I'd greatly appreciate it. Thanks!
 
So I am finally going to bite the bullet and want to make sure I have this right

2x6 wood x 2 pieces @ 73" red

2x4 wood x 2 pieces @ 15" yellow

2x4 wood x 4 pieces @ 23 inches green

2x4 wood x 8 pieces @ 14 inches purple

2x4 wood x 2 pieces @ 73 inches

2x4 wood x 4 pieces @ 15" blue

1/2 plywood for sides

Does this seem like a good formula to building a stand for a 135 that is 72 x 18 x 25?

My plan is to fit a sump I have that is 48 x 18 x 16 underneath.
 
If you can do it I would suggest buying rough cut dimensional lumber (2x4, 2x6, 2x8,...) and planning it down yourself if you have a planer. This will allow you to have smooth and square edges. It will make joining much easier, and tighter. The reason a 2x4 is 1.5x3.5 is they have planned .25" from each side. Takes a bit more time, but I also have found that the rough cut has less twist, and curve (at least from the mills in my area).
 
crvz,
I ran the numbers. You have an effective gap of 61" spanned by the 6.75" X 1.375" board which results in a deflection of .125" for a distributed load. This is right at what I think of as a limit. It by no means predicts a failure as the tank glass will take some of the load.

TheFishMan65,
A single 2X4 with supports on each end is not stiff enough for supporting that kind of load. Using the distributed load formulas in the Machinery's Handbook, the length is 65" (72" - 3.5"*2). The offset from each end is 8.5" (12-3.5"). By going to a 2X6 the deflection in the center drops from .31" down to .08". An alternative to this would be to install support legs inboard of the ends of the stand like I did for my stand.
Stand75g1.jpg


Brando457,
My only problem with your numbers is the 25" height on the stand. Between the 3.5" of the bottom frame and the 5.5" of the top frame, you will be hard pressed to get a sump between the two frames. Consider making it taller so that you can 1) get the sump into the stand, and 2) get a decent skimmer in and out without undue aggrivation.

RocketEngineer
 
Rocket, I if uder stand you. The 2x6 will hold a 4 foot tank witha deflection of .08 inches so no center support is needed. Where did the .31 deflection come from was that with a 2x4?

I think there was a miscommunication somewhere. I want to uses a 4x4 in each corner.

Thanks
 
TheFishMan65,
If you used an unsupported 2X4 for the front beam, the deflection would be .31" in the center. If you used a 2X6 front beam, the deflection would be only .08".

I would caution against 4X4s. They have a nasty tendency to twist/warp/split over time simply because the wood doesn't dry evenly and the outside shrinks more then the inside. Using a pair of 2X4s screwed together is just as strong and much more stable over the long haul.

RocketEngineer
 
RocketEngineer said:
crvz,
I ran the numbers. You have an effective gap of 61" spanned by the 6.75" X 1.375" board which results in a deflection of .125" for a distributed load. This is right at what I think of as a limit. It by no means predicts a failure as the tank glass will take some of the load.
Click to expand...

The obvious solution is to just stick a middle support to the floor I suppose, but I really want to avoid that if possible. What if I add in another 2x8 (though it will be the same size at around 6.75" x 1.375") in the configuration below (with support legs as well). This would only be done on the back (so the pieces displayed in white), as the front of the tank has the 2x4s of the framed wall providing more structural support and I don't think it is necessary to double up the 2x8 in that location. The tank itself would still sit mostly over the original 2x8 in the back, but they would be glued together and have the support to the floor, and I am covering it all in a 3/4" oak plywood. Does this help, or should I consider a different redesign?

I would also add the 2x4 cross beams (in white) to help stabilize the open area of the stand.

300dd_support_stand_rev2.jpg
 
crvz,
The addition of a second beam would double the strength so you will be well under the limit at that point. If you glue and screw the beams together as well as have a plywood top, they would effectively pick up the load at the same time. Some folks say this design is overbuilt but I take piece of mind over a little money any day.

RocketEngineer
 
You must log in or register to reply here.

Similar threads

E
Neptune DDR diy question for AWC
Replies
3
Views
366
Reefing102
Reefing102
B
Beam Deflection - 15 years and I finally broke down and wrote a how to.
Replies
16
Views
1K
BeanAnimal
B
sauceyreefOG
New (but old) Member - Hello!
Replies
12
Views
523
Reefing102
Reefing102
adova
300g DIY Acrylic Tank Recommendations
Replies
5
Views
351
griss
griss
AquaticReefTV
DIY Cable management time lapse
Replies
1
Views
671
S|\/|S
S
Back
Top