Acrylic Thickness

[nzafi]

I am looking into getting a tank that is 7-8ft long and up to 30in tall and just want to confirm how to determine the thickness of acrylic required. I have done searching and used various calculators posted in this forward and on google but kinda get mixed results. The thickness the company is saying they will use is 1in and I want to make sure this enough. Here are my questions:
1) When calculating the required thickness do you just take into account expected water or height of the tank. For example, a 30in tall tank with 1in acrylic will have max 28in of water but more likely it will be 26-27in. This can have a big impact on the output. Different calculators take different approaches.
2) How much bowing is expected? I am assuming unless you go nuts, there will be bowing no matter what? I want to avoid the horrid bowing that there have been several threads about recently.
3) Are there different grades/quality of acrylic? I know that cellcast acrylic must be used but is all acrylic equal? How does age impact this?

 

[thebiggerthebetter]

Have you read wednesday13 write-up? http://www.monsterfishkeepers.com/forums/threads/weld-on-40-and-42.544585/

You must have read Heidi's thread too that's recent.

Ignorant me thinks 1" acrylic with top bracing should hold her fine, if the seams are made to specs. You may ask the manufacturer to do an analog of eurobracing inside your acrylic tank for a little more $$, which will provide much more safety and peace of mind.

 

[Yuki Rihwa]

3) Are there different grades/quality of acrylic? I know that cellcast acrylic must be used but is all acrylic equal? How does age impact this?

*Everything has a price! We don't expect someone buying a Chinese Car and wanted it to look and performance like a Ferarri
*I watched a program about professional grade acrylics that Public Aquarium using around the world for their million gallons tanks, I though its just a 1 piece 12+ inches thickness acrylic but I was wrong, it was created with a bunch layers of smaller thickness acrylic for example 12 inches thickness = 6x layers of 2 inches thickness acrylic put together, like 2 inches thickness of flywood a lot stronger than a pure 2 inches 1 piece of wood, of course buying those material would cost you an arm and a leg or even your soul to make a top notch aquarium

 

[wednesday13]

1" is overkill for 30" tank height imo... plenty tanks out there in 1/2" at 30" height... yes 1/2" will bow at 30" tho. Id save some cost and meet in the middle at 3/4" material. Will be plenty to prevent any bowing at only 30" height. If your insistent on using the 1" it will be more than fine and shouldnt bow at all. Get a quote for the tank in 3/4" and 1"...weigh ur options after that. Id imagine itd be atleast a $500-800 difference if not more.

 

[nzafi]

From every calculator I have reviewed it is a combination of length and height, and number of the calculators had 1in as the requirement for 8ft x 30in. Ultimately it seems like the seams and overall quality also need to be considered.

I found a lot of great deals with aquartaquarium, which after searching on MFK scared the crap out of me.

 

[Yuki Rihwa]

From every calculator I have reviewed it is a combination of length and height, and number of the calculators had 1in as the requirement for 8ft x 30in. Ultimately it seems like the seams and overall quality also need to be considered.

I found a lot of great deals with aquartaquarium, which after searching on MFK scared the crap out of me.

If you intent to used cell cast acrylic then 1" thickness would prevent bowing, If you order a custom built then make sure that builder has a good reputation and using cell cast acrylic too.
Here is a quote from a document about acrylic:
"The bottom line is, understand what your application requires before you select a product to use. Not all clear acrylic is created equal for all applications, and the price should be the last consideration when planning your project, not the first. Most problems occur when purchasing people buy a “deal” on clear acrylic without fully understanding its intended end use. This unfortunately is not the fault of the Acrylic chosen, just the person choosing it unwisely."

A full document can be reach from here:
http://www.acrilex.com/what-are-the...continuous-cast-and-cell-cast-acrylic-sheets/

 

[Tropical Joe]

Stay away from anything less then 1 inch. Make sure you have top bracing. 1 1/4 inch acrylic would be great. Some people may say that it is overkill however, it will not bow and it will be forever. Price out the difference. If your not the type that changes tanks and this will be your baby go with 1 1/4 acrylic you wont be disappointed. 1/2 inch acrylic will 100 percent bow. Make sure the builder knows what he is doing with glue joints (no Bubbles). Good Luck

 

[Lepisosteus]

I agree at 30" height 3/4" acrylic with a full brace top is plenty strong

 

[DN328]

Independent of where you decide to have it built, I would also call around (the US?) to get a sense of what all the various BUILDERS would recommend. Some may be out to make a buck and say whatever, but hopefully you'll get a few that are fairly consistent in terms of safety factor and what is recommended.

At 30", I think I'd feel much better having both top/bottom Eurobrace regardless of acrylic thickness, but that's just me. Hopefully you will come across some honest and good builders that will give you the facts.