Stand for a 40 breeder and 2 20 gallons

[The Punisher]

For the steel stand guys, would this stand design work for a 40 breeder and 2 20 gallon tanks?

http://i932.photobucket.com/albums/ad165/willdumas/e84c9120.jpg

http://i932.photobucket.com/albums/ad165/willdumas/f5ecfe0c.jpg

[The Punisher]

Forgot to add that it will be made of 1" x 1" square tubing, 1-8" wall thickness.

[uncleof6]

Rather than do a protracted post on steel stand design, I will leave you with two basic ideas.

1) An aquarium requires direct vertical support under the footprint of the tank.

2) Think of your 1" steel tubing, as cooked spaghetti noodles*, as this is the way unsupported steel will act (to a far lesser degree, but nonetheless.) It is called deflection.

*kcress

Jim

[The Punisher]

That's definitely what I was thinking but was hoping to get away with the 45 degree pieces to support and kind of do the same thing as the vertical supports. I'm by no means an engineer but I had the thought that the downward force would be transferred along the 45 and into the vertical steel leg. That could be completely flawed logic, which is why I asked for advice here. Does my thinking make any sense at all?

[Qwiv]

Hey Punisher:

Interesting design idea, but there are some issues. You only show cross bracing in one direction, you should include both directions. Also, the cross bracing not extending all the way to the base and corner is inefficient creating moments in the structure that is designed on the light side. I would also like to see either larger horizontal members along the top or more vertical supports. What are you trying to achieve from a design point of view? Are you skinning the stand with something like plywood? A strong veneer can actually improve the strength of the stand a great deal if a good attachment method is used.

[The Punisher]

The stand will definitely be skinned in plywood but it will be removable so I can't rely on it to strengthen the stand at all. I guess I just need to get back to the drawing board and add more vertical supports and cross bracing. Thanks for all the help.

[Qwiv]

Do you really need to remove the back?

[The Punisher]

Good point, and no, I don't need to remove the back. I could also probably get away with permanently attaching one side as well. Would the added strength of the wood (along with cross bracing the sides) be enough to make my design work? I was also considering taking the two front 45's out and replacing them with verticals in-between the 40 and each 20. Does that sound any better?

[The Punisher]

The one thing I'm trying to get away from is putting verticals on the inside of the stand at the rear of the 40. I don't know the best way to support the back of the 40 without the verticals.

[The Punisher]

I've played around with it a bit and think I've got a better design. This is it:

http://i932.photobucket.com/albums/ad165/willdumas/4ccf3536.jpg

Does that look better?
The pieces on the bottom are to support a 55 gallon sump.

[uncleof6]

3) Do not rely on the welds.

J

[The Punisher]

3) Do not rely on the welds.

J

Really? Why do you say that?

[uncleof6]

Really? Why do you say that?

Never mind. Was being cross eyed.

Jim

[Qwiv]

If you attached the back, top, bottom and one side + added a removable cross brace to the second side, you would need no bracing at the front. Without getting fancy, you need to create a 5 sided structure to deal with all the lateral forces, like a box on its side.

Also, is you securely attached the siding and use strong enough plywood, you can eliminate legs. Look at most commercial stands and your kitchen cabinets.

You need to focus on building a strong top frame that doesn't deflect to much. That is the most important part of building a strong stand, then lateral bracing. The 1" x 1" over the opening under the 40 gal should be beefed up.

[The Punisher]

Ok, so the 1x1 under the back of the 40 should be beefier. Are you thinking thicker walled 1x1 or something like 1.5" 1/8" wall thickness. Thanks a bunch for the guidance so far.

[uncleof6]

What you need to deal with is unsupported spans over ~2 ft long. That back section (because the stand does not fit the foot print as a stand should) is really just hanging by the welds, and should be vertically supported directly underneath. Rectangular tubing solves the span issue, but getting it not to hang from the welds, is why I backed off earlier, ain't figgered that out yet.

Jim

[The Punisher]

Well I was planning this thing so that the entire underneath area could be as open as possible in order to fit a sump that I already have, which won't work if I have to put legs directly underneath all 4 corners on all 3 tanks. I guess it's back to the drawing board.

[scbrooks87]

Jim- Just based on a machining background here, not an engineering background... It seems that one back bar supporting the back of the 40g tank would probably (hate using that word) still be ok... The front of the tank is directly over verticals, and the side have the 40 degree supports, the back section shouldnt cause an issue as the welds, if done properly, can be plenty of strength.

I know I MIG welded a stool in machining class in school, it basically a 2"x2" flat piece of steel welded around the edges to the bottom part of the stool's seat, it was then given a field test by the instructor and they could break the weld with several hundred pounds of sheer force in any direction...

Again, not an engineering background... Just seeing if it could really become that much of an issue?

-Scott

[The Punisher]

That's kind of what I was hoping and thinking. I always assumed that welds were strong enough for this especially being a smaller aquarium. But, like you I have no engineering background.

[Qwiv]

Don't listen to Uof6, he thinks he is budah or something. If you know how to weld, you will be fine. If you don't know how to weld, have someone help you. Your welds are pretty easy and don't have any large moments in them, so you are fine. All your connections are mostly in shear.

I'd put 1.5 x 1 under all 4 sides of the 40 gal. All that added steel in the middle bottom would be better served by a 1/2" sheet of plywood. You can eliminate the added verticals and horizontals under the small tanks.

If you send me your sketch up file I can help you out.
How are you planning on protecting the metal stand from the saltwater?

[uncleof6]

Don't listen to Uof6, he thinks he is budah or something. If you know how to weld, you will be fine. If you don't know how to weld, have someone help you. Your welds are pretty easy and don't have any large moments in them, so you are fine. All your connections are mostly in shear.

I'd put 1.5 x 1 under all 4 sides of the 40 gal. All that added steel in the middle bottom would be better served by a 1/2" sheet of plywood. You can eliminate the added verticals and horizontals under the small tanks.

If you send me your sketch up file I can help you out.
How are you planning on protecting the metal stand from the saltwater?

So you figure making personal attacks makes you right? Considering I have not addressed anything that you have said..........

[Qwiv]

If you consider being compared to Buddha an attack. It would be nice to see you actually provide some good advise sometime instead of throwing out koan questions and criticism like your some sort of philosopher.

Punisher:
What are you planning on doing in the space behind the 40 gal? You could make a great external overflow or refugium back there. You might want to consider while designing the stand.

[Nanook]

[flamealert]

[Nanook]

Let's keep it clean here folks or infractions and bannations are going to be handed out like candy at Halloween;)

[Qwiv]

Haha. That boiler plate is funny.

[The Punisher]

I was planning on doing external overflows on all 3 tanks. They would then drain into a common sump. And as far as uncleof6 is concerned, I respect his opinion 100%. He tends to err on the side of caution more than most, but thats exactly what I like to do and that's why I ask these questions. I'd rather have an overbuilt stand than one that's just barely able to hold my tank/tanks.

[scbrooks87]

Punisher... I got to thinking, If you want to be a little more careful with this and have more support for that back piece, I'm thinking that if you take that 45 degree cross brace out from the center back of the stand, and add 1 or 2 vertical pieces in it's place, you could add a couple small 45" braces from the back bar for the 40g to those verticals like you have done to add strength to the sides of the tank.

Then to replace the 45 degree piece which is giving you sheer strength side to side, just add those pieces to the top or bottom corners in the back, they only need to be a few inches long to provide all the sheer strength you need.

I hope you can get a mental image of what I'm saying as it would take more time than I have to do a sketchup of it. Otherwise if you can email me the sketchup file i can play around with modifying yours lol.

-Scott