henward Posted November 18, 2007 Report Share Posted November 18, 2007 8mm and 10mm i am told how long and wide is not the problem is how high is this true? Quote Link to comment Share on other sites More sharing options...
Warren Posted November 18, 2007 Report Share Posted November 18, 2007 Read this, it will answer all your questions about glass thickness for aquariums... Read it thoroughly though. http://www.fnzas.org.nz/articles/techni ... _complete/ Quote Link to comment Share on other sites More sharing options...
alanmin4304 Posted November 18, 2007 Report Share Posted November 18, 2007 The higher the tank the more head of water and therefore pressure at the bottom. The longer the tank the more flex in the glass. The width is not a problem until it gets longer than the length. Quote Link to comment Share on other sites More sharing options...
Barrie Posted November 18, 2007 Report Share Posted November 18, 2007 get in touch with a glass merchant and ask what weight the glass is safe for Quote Link to comment Share on other sites More sharing options...
Warren Posted November 18, 2007 Report Share Posted November 18, 2007 get in touch with a glass merchant and ask what weight the glass is safe for Most don't know and have little or no experience with aquariums. Use the calculator in the link above with a safety factor of 3.8 then you know for sure. You can't beat the maths behind it... Quote Link to comment Share on other sites More sharing options...
OscarBoy Posted November 19, 2007 Report Share Posted November 19, 2007 my tank has 10mm thick glass and it is 100cm long 75 high and 50 back. im thinking of getting a tank made around 7ft but wat would i do 4 a stand? Quote Link to comment Share on other sites More sharing options...
Barrie Posted November 19, 2007 Report Share Posted November 19, 2007 Warren I dissagree. who knows better than a glass merchant on the strengh properties and weights that glass was design to hold? Feel free to contact PPG (USA), Pilks ,Glavabel, or a host of other manufactures for their recomendations. Part of my advanced trade cert (4 years plus 6 months) was on aquria and loadings (not on spelling though :oops: ) Quote Link to comment Share on other sites More sharing options...
evilknieval69 Posted November 19, 2007 Report Share Posted November 19, 2007 You can't beat the maths behind it... Im not sure i agree with that, but i can't explain why :lol: Quote Link to comment Share on other sites More sharing options...
Warren Posted November 19, 2007 Report Share Posted November 19, 2007 Im not sure i agree with that, but i can't explain why :lol: Are you any good at calculus?? Do the research and maths and you'll find I'm correct. The glass thickness article is based on common engineering practices and recommendations from Pilkingtons. I think they have the experience to make a safety factor recommendation. There is no black-art, how do you think buildings or bridges are designed - trial and error?? Calculation is the cost effective way to make sure you do not over design while making sure you meet a statistically safe safety factor. It's all standard engineering practice - trust the maths. If you cannot, then you'll never enter a tall building or cross a bridge again. To question designing aquariums by calculation but not bridges or buildings baffles me - maybe I've been an engineer too long... As I stated earlier, there are very few glass merchants who know anything about designing aquariums... However, if you find someone with good experience go with them as they'll be your best best. DIY without proper knowledge is a potential disaster waiting to happen. Quote Link to comment Share on other sites More sharing options...
livingart Posted November 19, 2007 Report Share Posted November 19, 2007 professionals built the Titanic amateurs built the Ark Quote Link to comment Share on other sites More sharing options...
Warren Posted November 19, 2007 Report Share Posted November 19, 2007 my tank has 10mm thick glass and it is 100cm long 75 high and 50 back. Your tank's front and back glass has a safety factor of 1.75 (or 175% of the breaking strain of the glass). While this is a long way off the recommended 3.8 there are many tanks with similar loadings out there. They usually survive for years but obviously do not have as much tolerance for movement (eg earthquake) as a tank designed to the recommended minimum. To meet the 3.8 safety factor your tank should have 15mm front and back glass, 10mm side glass and 12mm bottom glass. Quote Link to comment Share on other sites More sharing options...
Warren Posted November 19, 2007 Report Share Posted November 19, 2007 What ark? Quote Link to comment Share on other sites More sharing options...
evilknieval69 Posted November 19, 2007 Report Share Posted November 19, 2007 Sorry i was thinking of something different, ie the 3mm glass thread. Yea a tank may hold water if its made of 3mm glass, but theres a very high possibility that it will go bust at any time with any sort of knock etc. When i read your 'you can't beat the maths behind it...' statement i instantly thought 'well can you?'. Now i actually think about it a bit more, i guess you can't, as long as you use it correctly (ie figure out what thickness you need to make it a 3.8 + safety factor) I was thinking about the lower safety factors that the maths says will hold water, but may not physically.... Did you understand anything i just said? And no, im not good at calc, why you ask? :lol: :oops: Quote Link to comment Share on other sites More sharing options...
Warren Posted November 19, 2007 Report Share Posted November 19, 2007 Yes, you can make a tank to a safety factor of 1.00 if you want and it might hold the water - just don't bump it. The safety factor of 3.8 come from years of statistical analysis on building aquariums and the typical purity of glass. It allows for the common defects found in the glass during manufacture and the general wear and tear an aquarium is likely to see during it's life. Obviously it cannot cover every situation. However, a safety factor of 3.8 means an aquarium if designed using the correct methods and using the correct glass thickness will have less than 0.1% chance of failure over a 10 year period. Quote Link to comment Share on other sites More sharing options...
Warren Posted November 19, 2007 Report Share Posted November 19, 2007 Warren I dissagree. who knows better than a glass merchant on the strengh properties and weights that glass was design to hold? Feel free to contact PPG (USA), Pilks ,Glavabel, or a host of other manufactures for their recomendations. Part of my advanced trade cert (4 years plus 6 months) was on aquria and loadings (not on spelling though :oops: ) The engineer who designs the aquariums and wrote the guides and charts glass merchants use... I have contacted Pilkingtons and that's where the 3.8 comes from along with many other aspects for how the calculations were derived. I think there's skope here for properly engineered aquariums and experience. A good glass merchant with the appropriate knowledge and experience is key to a good aquarium design. There are only a handful of these people in NZ however and most of them have been mentioned on this website. Quote Link to comment Share on other sites More sharing options...
Ira Posted November 19, 2007 Report Share Posted November 19, 2007 Even the local glazier here in Wellington that tons of people have had make tanks, including me, doesn't really seem to know anything about the math or specific glass strengths behind building tanks. He seems to go more by experience. I may be wrong though. Barrie, if he doesn't know why do you think a guy who does nothing but cut and install house windows to government regulation specs would have a clue? Quote Link to comment Share on other sites More sharing options...
Barrie Posted November 19, 2007 Report Share Posted November 19, 2007 if he hasnt got a clue, its because he hasnt bothered to read the manuals Maybe I should look at a copy and paste of what we have to go by... I will look into it There are a lot out there that dont love the trade but just treat it as an income just as there are go mechanics and those that fix cars. I love my trade and am working on new glazing methods for the instalation of double glazed units. I only know of 2 others that can be bothered doing this. I suppost that what both Warren and myself are saying is that there are good and bad ways of doing things, the good ways have plenty of strengh and are based on figures, the bad ways are from those that just do it to make money? An interesting thing though has come to surface and that is that both Warren and myself are using 2 different types of data from the same manufacture. I will be emailing them to see why there seem to be conflicting information Quote Link to comment Share on other sites More sharing options...
Warren Posted November 19, 2007 Report Share Posted November 19, 2007 Hi Barrie, It's not two sets of data from the same supplier. My data is what I worked out myself with guideline information from Pilkingtons and from their glass datasheets. There was nobody at Pilkingtons NZ or Australia who could (or would) do the maths involved with the calculation of glass thickness for aquariums - didn't go further than this though (I'm sure someone there in another country knows how to do it). What I've come up with gives very similar results to the Pilkingtons tables for glass thickness for aquariums. What it does over what the Pilkington tables is tells you the exact thickness required for a tank of given dimensions and can mean a glass thickness less or more + it covers dimensions outside their table. The Pilkington table gives bands that could mean glass thicker than required gets used - increasing cost. You sure are right about the passion for what you do. It means the difference between a good job and something else... Quote Link to comment Share on other sites More sharing options...
Barrie Posted November 19, 2007 Report Share Posted November 19, 2007 Try Pilks UK Pilks NZ are like Metro (my supplier) and are just retailers and whole sellers. Another person that is considered the godfather of glass is Alan Sage who works out of Metro Central and is a contracted advisor. Just out of interest, The floor in the Sky Tower is 25mm think and NOT toughened but is laminated. The makeup is 12mm/1mm interlayer/10mm this has nothing at all with the subject but I thought some may find it interesting :oops: Quote Link to comment Share on other sites More sharing options...
OscarBoy Posted November 19, 2007 Report Share Posted November 19, 2007 well i got my tank from hutt pets so id thought they would have got 1 that was made right!!! Quote Link to comment Share on other sites More sharing options...
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