Thoughts on extruded aluminium stands?

[David R]

Examples;

DIY Extruded Aluminum Stand & 150 Tank Build

So I wanted to share my experience building a stand for a new 150 gallon tank I'm working on. I used the same method to build the one for my 80 gallon tank as well! First step was to measure the new tank and decide what I wanted the dimensions of the stand to be. From here it was just a matter of...

indmas.org

Trade Me

www.trademe.co.nz

I mean they obviously work, but as someone who's stuck with welded steel for anything over ~120g they just look flimsy AF to me! Very little diagonal bracing and a whole lot of faith in those corner brackets, we do get the occasional small-ish earthquake in my part of the world. I'm looking at setting up something in the region of 200-250g in the coming year, just starting to plan the build.

 

[Sassafras]

If you've done steel previously, I can understand questioning aluminum, especially looking at the relatively tall stand with tiny inside corner gussets in your link. Extruded aluminum construction is flexible in the sense that you can "over-engineer" as much as makes you feel comfortable, like many do with wood stands. In other words, if specs call for 2" extrusion, you can go 3". Bracing?, put in as much as you like, gussets, brackets, diagonals of any dimension. Here's what I did with a large tank I set up. It was spec-ed out with only 4 diagonal braces added to the basic frame. I added 12 more diagonal braces, 34 corner gussets and 20 corner angles! Lots of folks would call me crazy, since those additions weren't cheap, but it makes me feel good. BTW, they are a blast to put together, kinda like Tinker Toys or an Erector Set for grown-ups.

 

[aquaticeye]

If you've done steel previously, I can understand questioning aluminum, especially looking at the relatively tall stand with tiny inside corner gussets in your link. Extruded aluminum construction is flexible in the sense that you can "over-engineer" as much as makes you feel comfortable, like many do with wood stands. In other words, if specs call for 2" extrusion, you can go 3". Bracing?, put in as much as you like, gussets, brackets, diagonals of any dimension. Here's what I did with a large tank I set up. It was spec-ed out with only 4 diagonal braces added to the basic frame. I added 12 more diagonal braces, 34 corner gussets and 20 corner angles! Lots of folks would call me crazy, since those additions weren't cheap, but it makes me feel good. BTW, they are a blast to put together, kinda like Tinker Toys or an Erector Set for grown-ups.

View attachment 1533003

Stellar setup

 

[Backfromthedead]

Im not saying they dont work but they dont instill a lot of confidence imo. The example you linked is one of the more sturdy looking versions ive seen though... those overlapping smaller tubular rods are a lot stronger than just one larger rod or angle stock like ive seen in other aluminum stands.

Im not sure what the advantages are to using aluminum over steel except for weight. Cant be any cheaper or less labor intensive.

I will admit that Sassafras setup above does look great and definitely sturdy with all that reinforcement. I really like the idea of using it for the canopy too. But i would argue the same stand could be done with lumber much more economically.

Sassafras what type of fastenings are being used on that stand? I cant tell for sure but looks like stainless steel?? Do you worry at all about long term issues with galvanic corrosion?

 

[aquaticeye]

I've looked into aluminum vs steel. The aluminum time over time has been vetted to be just as sturdy for weightbearing.

The cost is very different. Wood is cheap. Steel is more expensive. Aluminum Lego kits like the one above are the most expensive.

I've looked at all of the above stand options myself for a 450G tank

Wood would be about $500

Steel about $1500

Aluminum about $3000

 

[fishdance]

Go with whichever makes you comfortable and looks best (to you).

If not a Saltwater tank, I'd use steel as this will reduce the number of legs (even if not visible) and the tank can be easily shifted with a pallet trolley or hydraulic car jack.

 

[Sassafras]

"I will admit that Sassafras Sassafras setup above does look great and definitely sturdy with all that reinforcement. I really like the idea of using it for the canopy too. But i would argue the same stand could be done with lumber much more economically."

You are correct, lumber would be significantly cheaper. I have constructed many types and styles of stands and this was my first extruded aluminum. Really just wanted to give it a try. Not that I have money to burn (not at all), but cost wasn't my deciding factor.

" Sassafras Sassafras what type of fastenings are being used on that stand? I cant tell for sure but looks like stainless steel?? Do you worry at all about long term issues with galvanic corrosion? "

The fasteners are stainless steel. I bought most of my materials from Tnutz and AluFab and questioned both about the galvanic corrosion issue. I was actually disappointed that they weren't more knowledgeable on the subject. They mainly told me that the anodized coating on the aluminum offered protection against such corrosion. I did some research on my own and found that the ratio of the anode metal to the cathode was a significant factor in the corrosion rate. A large mass of aluminum fastened by a relatively small mass of steel results in slow and minor corrosion. Using aluminum fasteners on steel with the mass ratio reversed would result in faster and more severe corrosion. When I found that aluminum beams on bridges were held ion place with stainless bolts it relieved my concern greatly over this potential problem. I'll keep an eye on things, but don't expect problems over the expected life of my stand.

 

[Backfromthedead]

"I will admit that Sassafras Sassafras setup above does look great and definitely sturdy with all that reinforcement. I really like the idea of using it for the canopy too. But i would argue the same stand could be done with lumber much more economically."

You are correct, lumber would be significantly cheaper. I have constructed many types and styles of stands and this was my first extruded aluminum. Really just wanted to give it a try. Not that I have money to burn (not at all), but cost wasn't my deciding factor.

" Sassafras Sassafras what type of fastenings are being used on that stand? I cant tell for sure but looks like stainless steel?? Do you worry at all about long term issues with galvanic corrosion? "

The fasteners are stainless steel. I bought most of my materials from Tnutz and AluFab and questioned both about the galvanic corrosion issue. I was actually disappointed that they weren't more knowledgeable on the subject. They mainly told me that the anodized coating on the aluminum offered protection against such corrosion. I did some research on my own and found that the ratio of the anode metal to the cathode was a significant factor in the corrosion rate. A large mass of aluminum fastened by a relatively small mass of steel results in slow and minor corrosion. Using aluminum fasteners on steel with the mass ratio reversed would result in faster and more severe corrosion. When I found that aluminum beams on bridges were held ion place with stainless bolts it relieved my concern greatly over this potential problem. I'll keep an eye on things, but don't expect problems over the expected life of my stand.

Good stuff. Ive always been told SS fastenings on aluminum were "fine" but the opposite is bad. Cant think of why anyone would want aluminum bolts anyway...my thinking is that the underhanging bolts on the top part of the stand could be exposed to constant humidity which supposedly exacerbates the issue. Since youre already tuned in, im sure youve had a watchful eye on the whole thing.

 

[David R]

If you've done steel previously, I can understand questioning aluminum, especially looking at the relatively tall stand with tiny inside corner gussets in your link.

Haha that "tall" stand was a 400mm (maybe 450, can't remember) tall stand for a 2400x1200mm footprint tank! I wanted it couch-height and it worked out perfectly, would totally do that again if/when I build a big tank.

Your set-up looks amazing, and that stand looks a whole lot sturdier than the ones I'm looking at with the diagonal bracing. I like the adjustable feet too, that is something I'd like to incorporate this time around, the big stand you mentioned had about 40mm of steel washers shimming up one corner, who knew concrete slabs were so uneven! I'll look more into the aluminium construction, next time I'm in the city I'll try visit the guy who makes them and see what he can do, sometimes its better to see things in person. Cheers!

 

[Sassafras]

Yes, I love the adjustable feet and they are an option that can be incorporated into almost any type of stand construction. How right you are about concrete slabs being uneven. Mine was only off about 10mm, but it was so nice to be able to level it perfectly. They had wheeled castors that I could have used but I just didn't trust 5 tons of weight sitting on wheels.