Structural engineers: Please HELP with 7 foot DIY stand build.

[mjovic]

For a span that size, I recommend a 2X8 top frame to minimize deflection. The uprights and base can be 2X4. I recommend stabilizing boards between the front and back rails to ensure they don’t twist plus a plywood top.

Thanks, yes I plan to add boards between the top rails to help with racking. I also plan to skin 3 sides with 3/4" ply as well as the top and bottom. I modified my design to add in 1 support at 1/3 the span and plan to have 2 on the back side. This would give me an approx. span of 51.375". Do you see any issues with this span using 2x6 and skinning. I also plan to screw and glue all my joints. I would like to avoid a 2x8 so I can get a 75 gallon sump inside comfortably and have more room to work. Speaking of that do you see any issues with having it sitting directly on a 3/4" plywood base? I will need to shim up on side about 1/4" as my floor slopes to my drain. Will that amount of weight cause the plywood to bend?

 

[mjovic]

Just find a local welder, will do it cheap... can either powder coat or spray it.

Should easily be able to cover your desired span using metal.

I would love to go this route, but stand wouldn't fit down my stairs to my basement. I'm going to be doing the final assembly in the basement.

 

[mjovic]

I understand the question at hand but did the OP consider an aluminum profile stand?

I haven't see this approach very much. How is the strength of these compared to wooden stands? What manufacturer is considered trusted and reliable? Thanks for the suggestion! I'm running out of time since tank will be here in coming weeks and still need to finish my wall construction so I can build the stand (I'm doing a corner in-wall installation).

 

[mjovic]

Something like this in @Stang67 build thread would be awesome IMO and much easier to move than a solid wood stand. This is a 72x24 tank she has but could probably do one for a 84x30 I would think.

That's cool. I wonder if all the weight on 6 small feet is a good thing? I guess it works right?

 

[oreo54]

That's cool. I wonder if all the weight on 6 small feet is a good thing? I guess it works right?

Probably depends more on the floor composition.

72x24x36 Aquarium Stand (Kit-form) | Framing Technology

www.framingtech.com

 

[areefer01]

I AM an engineer and have been posting about wood stands for almost two decades. To quote “this is a case of go back and do it again” because that’s beyond sketchy.

In any of these stand designs, look how the load gets moved from the tank to the floor. In a good design, the legs are directly under the top so the load goes from board to board. All the screws do is keep it held in place. Trusting screws or nails to carry weight in an area where saltwater corrodes anything it can is asking for trouble.

Your thread is golden.

 

[Paul B]

I built mine out of redwood because it doesn't really warp or rot. I purposely built it with very little wood on wood contact to prevent water seep and I also wanted the front open with no supports.

My tank is 6' but if it were 8' I would have used 2X6s and the 4X4s I used for legs. All the hardware is hot dipped galvanised bolted through and all the supporting pieces of wood are chamfered into the upright supports.

 

[BZOFIQ]

I would love to go this route, but stand wouldn't fit down my stairs to my basement. I'm going to be doing the final assembly in the basement.

Alu stands are assembled onsite.

They come in pieces like lego blocks, you put it together where you want it when ready.

My new build is 83x32 and I went this route because I couldn't bring the stand into the basement in once piece.

The tank 83x32x25 was slid down the stairs sideways on its back, I couldn't do that with the stand that was 83x32x46

 

[BZOFIQ]

That's cool. I wonder if all the weight on 6 small feet is a good thing? I guess it works right?

I have 8 feet, on 83x32 - no problem at all.

 

[BZOFIQ]

Here are some choices in no particular order

Aquarium Stands | Framing Technology

www.framingtech.com

Magnum™ Aluminum Stands

Magnum open frame or cabinet style aluminum aquarium stands with designer panels. More sizes, finishes and styles. The sturdiest most versatile aluminum stand you can buy. Research the details. Magnum stands leave the others in the dust.

www.tenecoraquariums.com

Aquarium Tank Stands - Quality Extruded Aluminum Material

Get a fast quote on a customized, easy-to-assemble aquarium stand from AluFab. Quality extruded aluminum customized to your specifications

www.alufabinc.com

 

[BZOFIQ]

If you are dead set on wood, I would recommend you also consider this plywood design; which was my original choice.

 

[BZOFIQ]

BTW, my alu stand came like this

 

[Jmp998]

I built mine out of redwood because it doesn't really warp or rot. I purposely built it with very little wood on wood contact to prevent water seep and I also wanted the front open with no supports.

My tank is 6' but if it were 8' I would have used 2X6s and the 4X4s I used for legs. All the hardware is hot dipped galvanised bolted through and all the supporting pieces of wood are chamfered into the upright supports.

Shouldn’t the top sit directly over the legs instead of being bolted into them from the side?? Looks like you are depending on the bolts to support the entire weight with that design. If a couple of those bolts eventually rust out, the stand fails. Not trying to be picky, that is just what I always heard.


Or maybe it is partly directly on top and I am just not seeing the corner construction/chamferring clearly.

 

[BZOFIQ]

Shouldn’t the top sit directly over the legs instead of being bolted into them from the side?? Looks like you are depending on the bolts to support the entire weight with that design. If a couple of those bolts eventually rust out, the stand fails. Not trying to be picky, that is just what I always heard.


Or maybe it is partly directly on top and I am just not seeing the corner construction/chamferring clearly.

If you look at the 4x4 legs the top appears to be resting on top of a notch.

 

[shwareefer]

IMO, double 2x6 across the front, no need for center supports. Triple if you are paranoid. Glue and screw.

 

[MnFish1]

I would love to go this route, but stand wouldn't fit down my stairs to my basement. I'm going to be doing the final assembly in the basement.

I was actually wondering how you were going to get the tank down there

 

[Paul B]

Shouldn’t the top sit directly over the legs instead of being bolted into them from the side??

The top is resting on the legs. The legs are notched to accept the top. The bolts are just there to keep the pieces together and no real weight is on them. I was a commercial/Industrial construction electrician in Manhattan and had to build a lot of structural supports for very heavy transformers, generators etc. although most of those were made of steel.

No screws either. I would never use screws for structural support and I have a problem using plywood for anything that could get wet if I wanted it to last a long time unless it was marine Plywood which costs more than RedWood.

I tried to have as little wood to wood contact as possible so no sandwiching of parts. Thars when you have problems. I like strength through simplicity.

 

[oreo54]

The top is resting on the legs. The legs are notched to accept the top. The bolts are just there to keep the pieces together and no real weight is on them. ,

Think most missed the 4x4 (?) legs.
What do you think about "engineering" the 4x4 w2x4's? Glue and screw ..

 

[nuxx]

I would love to go this route, but stand wouldn't fit down my stairs to my basement. I'm going to be doing the final assembly in the basement.

You can have them build it to be assembled on site with slip joints and bolts.

I did that with the stand on my 150 gallon frag tank. Was too wide and tall to make it through an interior door.

 

[mjovic]

Alu stands are assembled onsite.

They come in pieces like lego blocks, you put it together where you want it when ready.

My new build is 83x32 and I went this route because I couldn't bring the stand into the basement in once piece.

The tank 83x32x25 was slid down the stairs sideways on its back, I couldn't do that with the stand that was 83x32x46

Yup, this is exactly what I'm planning. I even built a mockup out of 1x2's to make sure it would fit. I have a 90 degree turn at the bottom which makes mine particularly challenging as they'll need to briefly stand it up on it's short side to make the turn. Can you send me a link to the manufacturer you used for the aluminum system? I'd like to look into it a bit more. Thanks!

Edit: I should have kept reading! Thanks for all the links and pics!