Recommended glass thickness for 110 cm cube

Blackened · Oct 27, 2018

Hi all,

Designing a 110 cm / 44 inch cube tank with outer steel bracing on top and bottom.

Tank will also be euro braced on the inside bottom.

Would like to know what thickness of glass would suffice. The builder is suggesting 15mm.

Online calculators all seem to be towards rimless tanks?

Appreciate any technical assistance with this.

Thank you.

GoVols · Oct 27, 2018

Blackened said:
Hi all,

Designing a 110 cm / 44 inch cube tank with outer steel bracing on top and bottom.

Tank will also be euro braced on the inside bottom.

Would like to know what thickness of glass would suffice. The builder is suggesting 15mm.

Online calculators all seem to be towards rimless tanks?

Appreciate any technical assistance with this.

Thank you.

15mm seems about right, but I would want it to be Euro Braced around the top too.

That steel would scare me, any kind of rust would kill a reef real fast...

JMO...

and hope other's will chime in.

FWIW:
Stay away from Cadlights... :mad:

Mandelstam · Oct 27, 2018

Just discovered that the calculator that I normally use is gone from its website. What was good about it was that you could choose a lot more options and safety factors depending on the edge finish, bracing, etc. A lot of calculators I've seen keeps it all hidden and just spits out an answer that you don't know what factors are being used etc. One I just checked suggests 16mm for a 92cm cube, with a safety factor of 3.95. If you want to push the factor down more the edges must be high quality and polished. I think the recommended safety factor for glass with polished edges is 3 and for roughly ground edges 5.

What the calculator doesn't tell you is the width of the glue joint you must have for that kind of pressure and what steel bracing throws into the mix.

I don't think I would take any builders suggestion as gospel for a tank like that, unless they had documented builds that you can check up on of the same size. At least ask what they how they reached their suggestion.

Myself I would probably skip the steel bracing and up the glass a little to counter it.