Lots of talk of glass thickness, but what about plywood?

[Tinyfish12345]

I'm starting to plan for a 9 x 5 x 3H tank, and while the glass thickness is well documented, I can't find much on plywood bracing.

My issue is this: I want to build the back and 1 side out of plywood, since it will be in a corner. The other two panels will be fully glass in 3/4".

I plan to use pond armor to seal the tank, and it seems that the glass panels will adhere to that just fine with silicone. No issue so far - Euro brace across the glass, silicone to plywood.

So now the back panel. What do? I am thinking of using 3/4" birch/oak ply, but will that bow? I'd like to avoid going too thick with 2x4s sticking out. Would laminating a second sheet of plywood fix it? Would a Euro-style plywood brace work?

Thoughts? Any critique of the design is welcome. My pride is worth less than my fish.

 

[takagari]

Not really a set way, best bet, see what overs have done by going over the threads on here.
a 8'x4'x32" tank can be built with just 3/4 plywood and some euro bracing.
Has been done and will hold. you are extending over a sheet, so I would double the 3/4, so the seams are separate and euro brace it.
As for the front, I've yet to see just glass to plywood, most still trim the top and bottom, but a few have joined glass in the corner and it looks really good.

 

[kelz]

I'm starting to plan for a 9 x 5 x 3H tank, and while the glass thickness is well documented, I can't find much on plywood bracing.

My issue is this: I want to build the back and 1 side out of plywood, since it will be in a corner. The other two panels will be fully glass in 3/4".

I plan to use pond armor to seal the tank, and it seems that the glass panels will adhere to that just fine with silicone. No issue so far - Euro brace across the glass, silicone to plywood.

So now the back panel. What do? I am thinking of using 3/4" birch/oak ply, but will that bow? I'd like to avoid going too thick with 2x4s sticking out. Would laminating a second sheet of plywood fix it? Would a Euro-style plywood brace work?

Thoughts? Any critique of the design is welcome. My pride is worth less than my fish.

I would say use 2 3/4 plywood on each side to be safe. I did a 600 gallon plywood bottom tank with 1/2 Inch Tempered glass and 3 3/4 plywood and I used white pond shield 2 coats

 

[Tinyfish12345]

I would say use 2 3/4 plywood on each side to be safe. I did a 600 gallon plywood bottom tank with 1/2 Inch Tempered glass and 3 3/4 plywood and I used white pond shield 2 coats

Did you do any of the sides or back with plywood or glass on all sides? The only part I'm concerned about is the corners where I'm siliconing the glass to the wood.

 

[kelz]

Did you do any of the sides or back with plywood or glass on all sides? The only part I'm concerned about is the corners where I'm siliconing the glass to the wood.

I did all 4 plane glass. But the pond shield is really good. And when u do 2 coats just sand it a bit to silicone the glass to the plywood and u should have no problem. Just make sure u add enough silicone. Everywhere and touch up after clean and silicone again.