CORVETTE Posted April 20, 2009 Report Share Posted April 20, 2009 Very interesting i'm looking forward to see how the stand takes the stress. I'm interested in the crushing characteristics of the box tube or HSS (hollow structual steel). I noticed on the ends your legs don't run stright through on the bottom. They actually sit on top f the box tubing. IF nesscery you could also cap the ends of the box to add strength. before you put the tank and the glass and rocks on it figure out what everything added will weight then have a party an get all your friends to climb up there till you equal the weight needed....lol Link to comment Share on other sites More sharing options...
RD. Posted April 20, 2009 Report Share Posted April 20, 2009 It's not just how much weight or shear force that those feet can take, it's also how long they can take it for. Link to comment Share on other sites More sharing options...
rED O Posted April 20, 2009 Author Report Share Posted April 20, 2009 Thanks for everyones concerns Neil:obviously you don't understand structural strength of these 1'' bolts. I am taking peoples advice on this but the bolts will not fail. We our going to make metal plates for under the feet. Our floor is not level at all and it would be a pain in the @$$ to shim it rather then just turning the blots with a wrench. Also if the tank is ever moved to a new location what do I do? shim it again? In my mind that is not the best way of doing it. The bolts are locked into a large nut that is welded inside the legs, I think thats a great design. Link to comment Share on other sites More sharing options...
RD. Posted April 20, 2009 Report Share Posted April 20, 2009 (edited) I understand more than you think. I'm not saying that they will fail, but they are most definitely the weakest link in the overall design of that stand. If you feel comfortable with the structural integrity of those feet, I guess that's all that matters. Edited April 20, 2009 by RD. Link to comment Share on other sites More sharing options...
rED O Posted April 21, 2009 Author Report Share Posted April 21, 2009 I understand more than you think. Neil I don't think you understand the strength of these bolts. We could get away with 1/2'' bolts WE HAVE 1'' BOLTS. Just to let you and everyone else know... we are using SAE J429 Grade 5 medium carbon steel, quenched and tempered bolts. I looked it up for you to set your mind at ease Normal Size Dia. In 1/4 - 1 1" - 1-1/2" ( we are using 1'' ) Proof Load PSI (Mpa) 85,000 74,000 Tensile Strength Min. PSI (Mpa) 120,000 105,000 here is the site. http://www.rigging.net/Bolts.html just to let you know, even if we had ONE bolt. That one bolt could hold the tank. Tensile strength is less important here. The more important factor here is yield strength combined with the thread engagement with the 1'' thick nut. This is a over not a under design. This would provide ample strength for a load that will not exide 1000 psi on each bolt. THIS IS NOT A WEAK LINK OF THE TANK. If anything this is the strongest part of the design. http://en.wikipedia.org/wiki/Yield_stress you can read that if you like. here are some statistics for you about yield strength for the bolt we are using. Range (Inches) Proof Load (psi) 85,000 Minimum Yield Strength (psi) 92,000 ( thats a lot more then 833 lbs ) and thats only for one here ya go http://www.tessco.com/yts/customerservice/.../bolt_grade.pdf anymore questions? Link to comment Share on other sites More sharing options...
RD. Posted April 21, 2009 Report Share Posted April 21, 2009 Dustin - you keep saying that I don't understand, I understand just fine. lol Bolts fail all the time, probably every day there are bolts that have failed somewhere, for some reason. While those are impressive specs that you posted, and while I wish you all the best with this project, the reality is that the bolts are indeed the weakest link in the design of that stand. Remove the bolts and you have removed any & all possible potential of failure (short of a bad weld) in the legs of that stand. See link below ........ http://www.croberts.com/bolt.htm Best of luck with your new tank & stand. Link to comment Share on other sites More sharing options...
rED O Posted April 21, 2009 Author Report Share Posted April 21, 2009 Dustin - you keep saying that I don't understand, I understand just fine. lolBolts fail all the time, probably every day there are bolts that have failed somewhere, for some reason. While those are impressive specs that you posted, and while I wish you all the best with this project, the reality is that the bolts are indeed the weakest link in the design of that stand. Remove the bolts and you have removed any & all possible potential of failure (short of a bad weld) in the legs of that stand. See link below ........ http://www.croberts.com/bolt.htm Best of luck with your new tank & stand. usually bolt failure is from using them in them improperly or in the wrong apparatus. Bolt failure from corrosion, to much vibration,excessive heat ect or what ever the case may be. are you a engineer? We had a engineer and a draftsman help us design the stand. I think they would know what they are doing. Link to comment Share on other sites More sharing options...
rED O Posted April 21, 2009 Author Report Share Posted April 21, 2009 Dustin - you keep saying that I don't understand, I understand just fine. lolBolts fail all the time, probably every day there are bolts that have failed somewhere, for some reason. While those are impressive specs that you posted, and while I wish you all the best with this project, the reality is that the bolts are indeed the weakest link in the design of that stand. Remove the bolts and you have removed any & all possible potential of failure (short of a bad weld) in the legs of that stand. See link below ........ http://www.croberts.com/bolt.htm Best of luck with your new tank & stand. I will back up my point again. BLOTS DO NOT FAIL WITHOUT A REASON! On the link you sent me... they talked about the types of failures FAILURE AS A RESULT OF AN OVERLOAD ( the 1'' bolts will not be overloaded) FAILURE FROM LACK OF LOCKING MECHANISM ( we are also using heavy duty nuts) METAL FATIGUE A crack is often initiated at a flaw or stress ( that will not be the problem ether because the bolts are only holding 833 lbs each) CORROSION FAILURE ( we have a coat of paint primer and 2 coats of paint so we wont have to worry about that) it goes on and on... :boxer: Link to comment Share on other sites More sharing options...
skynoch Posted April 21, 2009 Report Share Posted April 21, 2009 It's good to see everyones concern on here but I would have to agree with Dustin on this one. I have seen this design used extensively out here in industrial and oilfield use for alot bigger tanks and areas with vibration. Some of these stands would have to be 20+ years on them. Link to comment Share on other sites More sharing options...
RD. Posted April 21, 2009 Report Share Posted April 21, 2009 Once again, I'm not saying that they will fail, just that IMHO they are an unnecessary component of a metal stand, especially if one is already planning on using steel plates under the legs. In a different life I worked in the oilfield service industry, and have seen the results of metal fatigue (including very large bolts) up close & personal. I understand all of this much better than you think. And Dustin, if you noticed under "metal fatigue", the author stated: Metal fatigue can be a result of a design deficiency as well as improper assembly of the part. You also seem to have missed the section on "Failure from Improper Manufacture". And please don't take this as some kind of personal slam on your stand Dustin, it's not. I was just weighing in & commenting on something that a number of other members had already raised concerns over. I'll admit that I'm perhaps overly cautious about these types of things, but with 400+ gallons of water at stake, I don't think that's such a bad thing. Link to comment Share on other sites More sharing options...
rED O Posted April 21, 2009 Author Report Share Posted April 21, 2009 (edited) Once again, I'm not saying that they will fail, just that IMHO they are an unnecessary component of a metal stand, especially if one is already planning on using steel plates under the legs. In a different life I worked in the oilfield service industry, and have seen the results of metal fatigue (including very large bolts) up close & personal. I understand all of this much better than you think. And Dustin, if you noticed under "metal fatigue", the author stated: Metal fatigue can be a result of a design deficiency as well as improper assembly of the part. You also seem to have missed the section on "Failure from Improper Manufacture". And please don't take this as some kind of personal slam on your stand Dustin, it's not. I was just weighing in & commenting on something that a number of other members had already raised concerns over. I'll admit that I'm perhaps overly cautious about these types of things, but with 400+ gallons of water at stake, I don't think that's such a bad thing. We could argue this all day... But thats not going to change anything. The bolts are not a unnecessary component, they make the stand better. So are you saying I should shim it? Our floor is warped and It would be a pain to shim and maneuver a stand over 350 lbs. Then if we ever move it shim it again? then what? we would have to shim it again? Metal fatigue, And in bolt failure how many bolts fail because of a design deficiency. Compared to the millions of bolts in service. 1 bolt in every 10 million might fail? if that? There is nothing wrong with the bolt idea, they are one of the stronger components. Edited April 21, 2009 by rED O Link to comment Share on other sites More sharing options...
rED O Posted April 21, 2009 Author Report Share Posted April 21, 2009 Also in the oil fields those bolts are under extreme pressure and stress from the pipe headers or whatever they are being used for. Way to much stress, vibration, excessive amounts of heat. The 1'' bolts I am using is on a static load for a :cuss: fish tank they are not in a oil field... There is nothing to worry about. Link to comment Share on other sites More sharing options...
Leon71 Posted April 21, 2009 Report Share Posted April 21, 2009 Dustin, I think you are missing the point. We are all aquarists with different ideas on how to build something or make things work with what we have. One of your other posts is about how expensive this hobby is. It would be an utter shame if you were to build this tank and have a $2 bolt be the demise of some wonderful inhabitants. Just being cautious. Take this advice however you like, and go what you think is best. Leon Link to comment Share on other sites More sharing options...
rED O Posted April 21, 2009 Author Report Share Posted April 21, 2009 Dustin,I think you are missing the point. We are all aquarists with different ideas on how to build something or make things work with what we have. One of your other posts is about how expensive this hobby is. It would be an utter shame if you were to build this tank and have a $2 bolt be the demise of some wonderful inhabitants. Just being cautious. Take this advice however you like, and go what you think is best. Leon Thanks Leon. I am taking everyones advice but I am backing up what is correct... I there is 833 lbs on a bolt that can take over 10 000 lbs. The bolts are being used as legs for a fish tank and are not in any great stress. There is nothing wrong with using bolts. If these bolts could not take 833 pounds, that would make any bolt size under 1'' could not take it ether? That would almost make bolts useless. They are designed to take massive amounts of loads. I am almost positive that buildings and sky scrapers are not held together with duct tape... Link to comment Share on other sites More sharing options...
boydo Posted April 21, 2009 Report Share Posted April 21, 2009 I really like the stand the gussets and stock size are very good, however the little legs and bolts cause some concern. Bi-directional movement with the significant weight on them could collapse them like a fat person repositioning on a cheap chair. I'm sure the bolts are very strong however torsion and movement above will have no mercy on a 1 inch bolt - remember that water movement is going add left-right-back-and forth movement. The next big question is how strong is the concrete it will be point loading on? FYI - most concrete slab-on-grade are at building code which is rated at 500 psi (this is crushing integrity). And you want to put 800-900 psi on it. These are some facts, With that said - I suggest removing the legs and level the stand on your floor then use flat bar at various thickness to level the stand - this distributing the weight evenly. I understand how hard you have worked on this and time spent, but please take a little more time to consider some of the good advice presented to you. Best of Luck! Link to comment Share on other sites More sharing options...
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