OP
OP
MarsRover
Well-Known Member
Okay, complete post on my A.G.E tank/stand issue. The information in this post is either fact of my own situation, or public record. (@chefjpaul @Skep18 @KingJason)
Ever since i got the tank, i noticed a "tick" "tick" settling sounding noise coming from it every once in a while. It was clear it was due to the loading but i figured it might be the "leveling feet" (just upside down hex head structural bolts) being back driven by the load on them or the plywood deck on the top of the stand settling out any residual stresses etc... I reported this to Chris Brenes, Acrylic and glass exhibits / The Fish Gallery (AGE) sales rep, who didn't really make much of it so i let it go.
Fast forward to more recently. While measuring my home/tank/stand to build my lower cabinets, i noticed this:
Video showing light coming through, from the other side of the tank, between the bottom of the tank and the top of the stand deck:
Video showing the sagging PVC bottom of the tank. The edge of the PVC sheet is visible between the tank steel bracing and the top deck of the stand....
Video showing me pulling out a full sheet of paper i inserted between the tank and the stand. I can actually push this paper all the way through to the other side....
Edges of PVC tank bottom showing under the tank bracing...
Light shining through between the bottom of the tank and the top deck of the stand...
Measuring the gapping between the tank and stand...
So, basically, not good... I have ~ 4mm deflection. I decided to do hand calcs to see what the situation was with the stand, as built, assuming a very non-conservative (i.e. not safe because it is too small!) design load of the dry weight of the tank, plus the weight of saltwater to fill it.
In this situation, 100% fixity cannot be assumed! So the true situation exists somewhere in between 0%-100% fixity. Regardless, the safety factor in the best case, 100% fixity, is still MUCH MUCH too low for something that risks this level of hazard to life and property!
Okay, so for @Skep18 this probably makes loads of sense from statics and mech. of materials class, but for the rest of you, the next bit is probably better. I decided that hand calcs show a bad situation but it ultimately ignores the angled pieces between the vertical legs etc... so finite element analysis is an easier way to communicate the problem more accurately. So i built the stand in CAD and ran an FEA:
My setup: Feet are fully fixed. Top of stand is holding the weight of the dry tank, the saltwater to fill that tank, and the deck of plywood that sits on top of the stand, under the tank. No rocks, no equipment, nothing else.
Here is the displacement with visual-magnification factor set to 1x. You can see max deflection is 0.128in (3.2512mm). Scroll back up to my previous photos and you will see i am measuring 4mm. This is the difference between a "perfect" stand (no welds, no holes, just magically this structure exists in perfect world) and real life. This discrepancy is, in part, EXACTLY one of the reasons when designing things engineers add additional safety factor to designs. Explanation of safety factor is next.
Safety factors: A safety factor of 1 means the structure is just barely designed to hold the load you're putting on it. Factor of safety of 2 means the structure is designed to hold twice the load you're going to put on it. I.e. safety factors equal are a multiplier on the intended load that something can withstand).
Safety factor to yield: "Yielding" is an engineer's way of saying "permanently bent". It is when you bend something and it begins to deform plastically, meaning, you bend it, you let go, and it does NOT go back into its original shape: it yielded/ plastically deformed (vs elastically deformed like a rubber band, which goes right back to where it was before you bent it). Generally speaking, yielding is considered failure in almost all engineering disciplines.
For some perspective:
Considering we are talking about massive tanks, massive amounts of water, and putting it into peoples homes who then put massive amounts of money and time into them, I'd hazard a guess that if this was controlled by US code, the required safety factors for stands on tanks >100 gallons would have to be somewhere in the ballpark of 2.5 to 5.
Stress: Now that i explained safety factors, let see what safety factor the simulation says the stand has to the weight of just the tank, the salt water to fill it, and the plywood top deck of the stand:
So, this is a little more complex to understand fully, so i'll try my best to keep you engaged as i explain: There is exists a small nodal region near where the angle supports meet the structure that's red. Stress level of 17.7 ksi. This might be an artifact of the simulation and geometry so lets give A.G.E the benefit of the doubt and ignore that. Everyone would agree that yellow is definitely in this structure though: 13.2886 ksi. The compressive yield strength of A36, common structural steel for square tube, is 22ksi (MATWEB). To calculate safety factor, we take the strength of the material and divide it by the max stress. Thus, if our stress is only half of the max strength of the material, then we have a nice safety factor of 2! So for this situation, we say our max stress is 13.2886 ksi (yellow color). And the material has a strength of 22ksi.
22ksi/13.2886ksi = 1.655 safety factor. In aerospace, we rarely have safety factors this low. And aerospace carries some of the lowest safety factors of ALL engineering. The reason why: we have to launch it into space so if it is too heavy, it won't get off the ground. So how does NASA get away with flying super expensive components with low safety factors? We test test test test test these pieces like crazy, then we analyze them like crazy with things like xrays etc.. to ensure that have testing them, they aren't damaged internally. Then we feel statistically safe they will perform in flight. This process is very expensive, hence why our projects cost so darn much. The cost and time to do this doesn't make sense for things like cars, tables, aquariums, so you over design them with a fat safety factor.
A safety factor of 1.655 on something that lives in peoples homes, exists in a corrosive environment (saltwater...), a dynamic environment (water motion), and risks serious hard to life and property, is insufficient and grossly negligent.
I emailed all this info to A.G.E, and the owner of The Fish Gallery / Acrylic and Glass Exhibits, Roger S Degregori (all this info is public fyi), told me that i am "over analyzing" this. We talked over the phone a few times and he admits that they have never engineered anything it is just based on his experience. He even went so far as to say he has a "sixth sense" for things like this. Kept saying if he had "seen anything concerning when [he] came to deliver the tank personally to my home he wouldn't have left it there risking failure". I repeatedly try to explain to him this isn't about a bad batch of metal or bad welds, it is about it just being under designed. He then went on to start blaming things i may have done etc... I don't want to go too far into this part of the issue. Suffice it to say, A.G.E takes responsibility for the failing stand and wants to try and "fix" it by either having me design a leg for them to make and on my time and dollar i'd have to attach it to the stand myself, OR, they send me a new stand and i have to break down my tank, which has that entire rock structure cemented to the overflow box, and swap it all out myself.... uhhh no thanks... not going to let them give it another "good ol' college try" at making a stand for me since by their owner's admission: no one over there knows how to use a calculator to design anything.
So now, now there is the issue of the tank. The center of the length of the tank is no longer supported, all the way across its width. As per A.G.E's warranty on their website:
http://www.acrylicandglassexhibits.com/About-Us
Thus, if this situation had been caused by another stand, the warranty on the tank would be null and void.
Multiple times i reiterated these points via email and over the phone:
Based on the above points, and the situation of my stand/tank, someone would be VERY VERY hard pressed to prove the joints of the tank have not been stressed beyond intent. Hence why this would void A.G.E warranty (if this hadn't been caused by AGE in the first place). Even with all of this, Roger maintains that because it is holding water presently, the tank is fine because it is built like “a brick s***house” (not a technical term so I have no idea what that means....). Roger also says that he “can’t promise it won’t break tomorrow” and he can’t show me any form of proof that it’s fine. I just have to take his unqualified-mechanical “word” for it.....
As everyone on here knows, even with a full refund, I have a LONG and likely expensive road ahead of me. I can't touch the stand to support it temporarily, and i can't go the route of designing something FOR AGE to fix this mess because my attorney has advised me not to as it risks producing a lack in clarity of culpability should damages need to be recouped legally. Makes sense.
I have found that Roger's attorney, or at least his attorney in a case in Texas court, is someone with the same last name (found via HCDistrictclerk.com case search). So it likely won't cost him to defend himself in court....which is probably why he is so brazen with me about not making good on their warranty, but I'm not worried.
On top of all of this, ever since i got the tank, and have been looking at other starphire tanks in person, i'm pretty sure i also didn't get the starphire glass i paid for on all sides:
Photo of my AGE glass edge on, camera right up against the cut edge of the glass with flash on:
A.G.E Glass again:
OCEANIC GLASS true starphire: edge on, camera right up against the cut edge of the glass with flash on:
OCEANIC GLASS (true starphire):
I have also done a similar FEA analysis on @KingJason 's tank stand. His deflection is much better than mine. Basically zero. But it looks like his safety factors are also around 1.5.... and his tank is nearly twice the size of mine
I'd hate to see what happens in an earthquake with our tanks....
....wonder if anyone actually will read all of this.... but this is why i now say NEVER BUY a tank from Acrylic and Glass Exhibits, The Fish Gallery, or anyone, for that matter,who doesn't say what the safety factor is on their stands.....especially if their response to that question is "huh?” ......ugh
What would you want if you found yourself in this situation?
..
Ever since i got the tank, i noticed a "tick" "tick" settling sounding noise coming from it every once in a while. It was clear it was due to the loading but i figured it might be the "leveling feet" (just upside down hex head structural bolts) being back driven by the load on them or the plywood deck on the top of the stand settling out any residual stresses etc... I reported this to Chris Brenes, Acrylic and glass exhibits / The Fish Gallery (AGE) sales rep, who didn't really make much of it so i let it go.
Fast forward to more recently. While measuring my home/tank/stand to build my lower cabinets, i noticed this:
Video showing light coming through, from the other side of the tank, between the bottom of the tank and the top of the stand deck:
Video showing the sagging PVC bottom of the tank. The edge of the PVC sheet is visible between the tank steel bracing and the top deck of the stand....
Video showing me pulling out a full sheet of paper i inserted between the tank and the stand. I can actually push this paper all the way through to the other side....
Edges of PVC tank bottom showing under the tank bracing...
Light shining through between the bottom of the tank and the top deck of the stand...
Measuring the gapping between the tank and stand...
So, basically, not good... I have ~ 4mm deflection. I decided to do hand calcs to see what the situation was with the stand, as built, assuming a very non-conservative (i.e. not safe because it is too small!) design load of the dry weight of the tank, plus the weight of saltwater to fill it.
In this situation, 100% fixity cannot be assumed! So the true situation exists somewhere in between 0%-100% fixity. Regardless, the safety factor in the best case, 100% fixity, is still MUCH MUCH too low for something that risks this level of hazard to life and property!
Okay, so for @Skep18 this probably makes loads of sense from statics and mech. of materials class, but for the rest of you, the next bit is probably better. I decided that hand calcs show a bad situation but it ultimately ignores the angled pieces between the vertical legs etc... so finite element analysis is an easier way to communicate the problem more accurately. So i built the stand in CAD and ran an FEA:
My setup: Feet are fully fixed. Top of stand is holding the weight of the dry tank, the saltwater to fill that tank, and the deck of plywood that sits on top of the stand, under the tank. No rocks, no equipment, nothing else.
Here is the displacement with visual-magnification factor set to 1x. You can see max deflection is 0.128in (3.2512mm). Scroll back up to my previous photos and you will see i am measuring 4mm. This is the difference between a "perfect" stand (no welds, no holes, just magically this structure exists in perfect world) and real life. This discrepancy is, in part, EXACTLY one of the reasons when designing things engineers add additional safety factor to designs. Explanation of safety factor is next.
Safety factors: A safety factor of 1 means the structure is just barely designed to hold the load you're putting on it. Factor of safety of 2 means the structure is designed to hold twice the load you're going to put on it. I.e. safety factors equal are a multiplier on the intended load that something can withstand).
Safety factor to yield: "Yielding" is an engineer's way of saying "permanently bent". It is when you bend something and it begins to deform plastically, meaning, you bend it, you let go, and it does NOT go back into its original shape: it yielded/ plastically deformed (vs elastically deformed like a rubber band, which goes right back to where it was before you bent it). Generally speaking, yielding is considered failure in almost all engineering disciplines.
For some perspective:
- Flight Spacecraft structures have design factors of safety to yield around 1.5 (they are EXTENSIVELY proof tested and post test analyzed with penetrating dyes, xray, etc... and only made from the highest grade materials available)
- For fixtures that hold personnel or flight hardware, the safety factors have to be 3.5 to yield and 5 to ultimate strength.
Considering we are talking about massive tanks, massive amounts of water, and putting it into peoples homes who then put massive amounts of money and time into them, I'd hazard a guess that if this was controlled by US code, the required safety factors for stands on tanks >100 gallons would have to be somewhere in the ballpark of 2.5 to 5.
Stress: Now that i explained safety factors, let see what safety factor the simulation says the stand has to the weight of just the tank, the salt water to fill it, and the plywood top deck of the stand:
So, this is a little more complex to understand fully, so i'll try my best to keep you engaged as i explain: There is exists a small nodal region near where the angle supports meet the structure that's red. Stress level of 17.7 ksi. This might be an artifact of the simulation and geometry so lets give A.G.E the benefit of the doubt and ignore that. Everyone would agree that yellow is definitely in this structure though: 13.2886 ksi. The compressive yield strength of A36, common structural steel for square tube, is 22ksi (MATWEB). To calculate safety factor, we take the strength of the material and divide it by the max stress. Thus, if our stress is only half of the max strength of the material, then we have a nice safety factor of 2! So for this situation, we say our max stress is 13.2886 ksi (yellow color). And the material has a strength of 22ksi.
22ksi/13.2886ksi = 1.655 safety factor. In aerospace, we rarely have safety factors this low. And aerospace carries some of the lowest safety factors of ALL engineering. The reason why: we have to launch it into space so if it is too heavy, it won't get off the ground. So how does NASA get away with flying super expensive components with low safety factors? We test test test test test these pieces like crazy, then we analyze them like crazy with things like xrays etc.. to ensure that have testing them, they aren't damaged internally. Then we feel statistically safe they will perform in flight. This process is very expensive, hence why our projects cost so darn much. The cost and time to do this doesn't make sense for things like cars, tables, aquariums, so you over design them with a fat safety factor.
A safety factor of 1.655 on something that lives in peoples homes, exists in a corrosive environment (saltwater...), a dynamic environment (water motion), and risks serious hard to life and property, is insufficient and grossly negligent.
I emailed all this info to A.G.E, and the owner of The Fish Gallery / Acrylic and Glass Exhibits, Roger S Degregori (all this info is public fyi), told me that i am "over analyzing" this. We talked over the phone a few times and he admits that they have never engineered anything it is just based on his experience. He even went so far as to say he has a "sixth sense" for things like this. Kept saying if he had "seen anything concerning when [he] came to deliver the tank personally to my home he wouldn't have left it there risking failure". I repeatedly try to explain to him this isn't about a bad batch of metal or bad welds, it is about it just being under designed. He then went on to start blaming things i may have done etc... I don't want to go too far into this part of the issue. Suffice it to say, A.G.E takes responsibility for the failing stand and wants to try and "fix" it by either having me design a leg for them to make and on my time and dollar i'd have to attach it to the stand myself, OR, they send me a new stand and i have to break down my tank, which has that entire rock structure cemented to the overflow box, and swap it all out myself.... uhhh no thanks... not going to let them give it another "good ol' college try" at making a stand for me since by their owner's admission: no one over there knows how to use a calculator to design anything.
So now, now there is the issue of the tank. The center of the length of the tank is no longer supported, all the way across its width. As per A.G.E's warranty on their website:
http://www.acrylicandglassexhibits.com/About-Us
Thus, if this situation had been caused by another stand, the warranty on the tank would be null and void.
Multiple times i reiterated these points via email and over the phone:
Based on the above points, and the situation of my stand/tank, someone would be VERY VERY hard pressed to prove the joints of the tank have not been stressed beyond intent. Hence why this would void A.G.E warranty (if this hadn't been caused by AGE in the first place). Even with all of this, Roger maintains that because it is holding water presently, the tank is fine because it is built like “a brick s***house” (not a technical term so I have no idea what that means....). Roger also says that he “can’t promise it won’t break tomorrow” and he can’t show me any form of proof that it’s fine. I just have to take his unqualified-mechanical “word” for it.....
As everyone on here knows, even with a full refund, I have a LONG and likely expensive road ahead of me. I can't touch the stand to support it temporarily, and i can't go the route of designing something FOR AGE to fix this mess because my attorney has advised me not to as it risks producing a lack in clarity of culpability should damages need to be recouped legally. Makes sense.
I have found that Roger's attorney, or at least his attorney in a case in Texas court, is someone with the same last name (found via HCDistrictclerk.com case search). So it likely won't cost him to defend himself in court....which is probably why he is so brazen with me about not making good on their warranty, but I'm not worried.
On top of all of this, ever since i got the tank, and have been looking at other starphire tanks in person, i'm pretty sure i also didn't get the starphire glass i paid for on all sides:
Photo of my AGE glass edge on, camera right up against the cut edge of the glass with flash on:
A.G.E Glass again:
OCEANIC GLASS true starphire: edge on, camera right up against the cut edge of the glass with flash on:
OCEANIC GLASS (true starphire):
I have also done a similar FEA analysis on @KingJason 's tank stand. His deflection is much better than mine. Basically zero. But it looks like his safety factors are also around 1.5.... and his tank is nearly twice the size of mine
I'd hate to see what happens in an earthquake with our tanks....
....wonder if anyone actually will read all of this.... but this is why i now say NEVER BUY a tank from Acrylic and Glass Exhibits, The Fish Gallery, or anyone, for that matter,who doesn't say what the safety factor is on their stands.....especially if their response to that question is "huh?” ......ugh
What would you want if you found yourself in this situation?
..
Last edited:
lol. 
