Aluminium tank stand design

[Misha]

Hello,

I'm planning to upgrade my tank stand, the tank is 60 x 60 cm and 35 height. around 120 litres.
I'm wondering If I should use 40x40mm or 40x80mm legs because with the 40x40mm the weights is on the screws and not the leg itself. The upper part is made with 40x80mm and the lower part is 40x40.

What do you guys think? Or am I overbuilding when using 40x80? The difference In costs are "only" 35 euro.

 

[Misha]

This is what I mean with: weight on the screw instead directly on the leg.

 

[theatrus]

I have about 85 liters on a 25x25 setup with 6 legs, but it does include a shelf 3/4 of the way up which acts as an anti-racking brace.

I think you'll be fine with 40mm legs. No need to go to 40x80. https://www.reef2reef.com/threads/d...2g-long-mini-build.534114/page-4#post-5841688

 

[tsouth]

It's 35 euro, the sanity is well worth the costs imo

 

[KimG]

Hello,

I'm planning to upgrade my tank stand, the tank is 60 x 60 cm and 35 height. around 120 litres.
I'm wondering If I should use 40x40mm or 40x80mm legs because with the 40x40mm the weights is on the screws and not the leg itself. The upper part is made with 40x80mm and the lower part is 40x40.

What do you guys think? Or am I overbuilding when using 40x80? The difference In costs are "only" 35 euro.

If its really only 35 euros then go with the thicker on. Peace of mind.
Do you mind if I ask where are you buying the aluminium from?

 

[Misha]

If its really only 35 euros then go with the thicker on. Peace of mind.
Do you mind if I ask where are you buying the aluminium from?

I’m planning on ordering from aluxprofiel. It’s a Dutch company.

 

[KimG]

Thanks

 

[tuesdayd]

I wouldn't want the weight on the fasteners...not good practice.

 

[Misha]

I wouldn't want the weight on the fasteners...not good practice.

Exactly my thought. So you’d replace the 40x40 with 40x80? A lot of stands I saw on youtube are build with the weight on the bolts.

 

[Reefer Reboot]

While I was doing a quick sketch for you I saw others chime in with the same idea. By using the 40x80 as the legs you will be transferring the load directly to the horizontal beams. The screws and bracket just hold it in place. 40x40 will be sufficient for the horizontal beams. The width of the 40x80 will stop the racking from front to back and some good corner plates or brackets will stop the racking from side to side. 120 liters (31 gallons) is not enough weight to worry about in this configuration. I have this basic configuration for my stand holding 130+ gallons.

 

[Misha]

While I was doing a quick sketch for you I saw others chime in with the same idea. By using the 40x80 as the legs you will be transferring the load directly to the horizontal beams. The screws and bracket just hold it in place. 40x40 will be sufficient for the horizontal beams. The width of the 40x80 will stop the racking from front to back and some good corner plates or brackets will stop the racking from side to side. 120 liters (31 gallons) is not enough weight to worry about in this configuration. I have this basic configuration for my stand holding 130+ gallons.

Thanks! Helps me a lot. Would it be better to use 40x80 as horizontals on the top part or would it make the structure weaker?

 

[Reefer Reboot]

It wouldn't make it weaker, in fact it would make it stronger. I just really think it's not needed, but if you want to use it, why not. It certainly won't hurt. Once you put the base board on top of the stand for the tank to sit on it will distribute the weight evenly.
Now go have some fun and build that stand!
Post some pics when you're done please.

 

[Misha]

It wouldn't make it weaker, in fact it would make it stronger. I just really think it's not needed, but if you want to use it, why not. It certainly won't hurt. Once you put the base board on top of the stand for the tank to sit on it will distribute the weight evenly.
Now go have some fun and build that stand!
Post some pics when you're done please.

I will post some pics. This is a pic of the 40x80 profile is the hollow part ok?

 

[Reefer Reboot]

Yes, using as legs you will be putting a columnar load on it. The horizontal pieces will be too short to have much (if any) deflection. There are load deflection calculators online from many of the manufacturer's of this material. Check it out and see what your numbers come out to. I use this a lot at work (so much so that the corporation I work at bought the manufacturer) and it is stronger than I think most people would give it credit for. A well thought out build plan goes a long way.
Speaking of work, I have to go there now. I'll be happy to answer any other questions when I get back. Good luck!

 

[Misha]

Yes, using as legs you will be putting a columnar load on it. The horizontal pieces will be too short to have much (if any) deflection. There are load deflection calculators online from many of the manufacturer's of this material. Check it out and see what your numbers come out to. I use this a lot at work (so much so that the corporation I work at bought the manufacturer) and it is stronger than I think most people would give it credit for. A well thought out build plan goes a long way.
Speaking of work, I have to go there now. I'll be happy to answer any other questions when I get back. Good luck!

Thanks! I looked up a load deflection calculator but had no luck finding an understandable one, any advice which one is good?

 

[Reefer Reboot]

I have only used the deflection calculator on 80/20.net. Just find a comparable profile of extruded aluminum from their product line and feed it into the calculator along with the length of the horizontal beam and estimated weight. Go to the red tab for "Supported 2 ends" (if you build it as I suggested), then click the red "Calculate Deflection" button. Now, keep in mind that this calculates all the weight onto a single beam. Your stand will have four beams in a box configuration. Plus you will have a supporting base board to sit the aquarium on, plus the rigidity of the aquarium itself. This will in effect distribute the load throughout the entire area of the "table top" (for lack of a better term). I ran a quick calculation using their lightest profile with about double the weight of the water in your tank. You should be able to expect a deflection of zero to maybe the width of a human hair to put it in layman terminology.
I get the sense that you are a little nervous about this, understandably so. As they say, a picture is worth a thousand words. So I will include this picture of my stand during my build phase.

36" cube tank on top (tank alone weighs 325 lbs), 36"x36"x24" cube sump/refugium below. 4080 Legs and 4040 horizontal beams (39" square "table top"). Rock Solid. Hasn't spilled a drop of water yet despite our California earthquakes.
Very admirable of you to do the research. Please double check my numbers. Let us know how it goes.

 

[Ratherbeflyen]

Everyone always gets too hung up bracing the center. As long as your stand will support the ends of the tank, it will be fine.