Best instructions/technique for large tank assembly

[karimwassef]

I'm about to embark on a dangerous journey and would like to ask for help.
I've built glass tanks as big as 6' x 2' x 2' and they held up well. But assembling 0.25"-0.5" thick glass isn't the same as 0.75"-1".

I'm looking for a recommendation (or link) to the best tank building technique or instruction for very large tanks. It's 8' x 8' x 2.5' and is a mix of 3/4" starphire and 1" regular glass. The bottom will have a metal frame with double stacked 4" eurobrace 0.75" thick. The top is completely open with a double stack of 4" x 0.75" eurobrace too - but no cross braces and no metal frame.

In planning: I've gotten as far as the room, a truck and a forklift to get the precut glass panels in the room.

Is the pin method still the recommended approach?

Also, if you're in the DFW area and would like to participate, please let me know.

I'm not in a rush so plenty of time to plan this out.

[Brunzy]

Can I ask what the pin method is? I'm looking at building a 6x2x2 haha! I would love to pick your brain on how yours went!

[jccaclimber]

I'm game to help, no clue what the current advice on spacers is.

[karimwassef]

actually the pin method is for acrylic tanks



here's a big glass tank build



and here's the easier small glass tank build



and here's how a pro does it fast

[karimwassef]

Here's Joey's 6'x6'x2'

[karimwassef]

So, here's what I like so far:

From Dramatic Aquatics:
1. I like the tape method for keeping things clean
2. I like the smaller 2nd glass plates on the bottom to keep the sides in place and add bracing.

From Joey's build:

3. I like the plywood bottom with pond armor epoxy.
4. I like the outside lip to keep the sides in place from the outside. Allows silicone to act as a sealant like a plywood tank window. I can see this working with item #2 from DA above to create a plywood groove for the side glass to fit into. This might be a good substitute to the metal frame bottom.

and here's what I'm worried about:

A. The professional assembly is fast. This means that the silicone doesn't have time to skin over. I won't be going fast, so I need a slow deliberate method.
B. My glass is large and thick and heavy. This will likely need at least 4 people to do safely.
C. I'll be buying the glass precut - if the panels are not perfectly square or slightly off in dimensions, it could seriously compromise the build.

[karimwassef]

Here's the equivalent to the "pin method" - the idea is the same - to create spacers and clamp the pieces in place, then apply the adhesive into the gap. This is Simuengco's build

[karimwassef]

Here's another advocate of the gap method









He uses toothpick thickness instead of zip tie thickness. He uses tape for the edges and on the opposite side of the gap.

[karimwassef]

so what is a reasonable gap for 3/4" thickness?

I'm thinking 1/8" to 1/4"?

[karimwassef]

Originally Posted by jccaclimber

I'm game to help, no clue what the current advice on spacers is.

Thanks! Glad for the help!

[SFish]

I've never used pins. I know Joey doesn't as well.

[karimwassef]

I haven't either but I've never done a very large build with 3/4" - 1" glass

[SFish]

I don't think you use pins on glass

[karimwassef]

Some people are using it. Some aren't.
It looks to be the most controllable method for someone who doesn't have the skill to go fast (like me).
It also should help reduce bubbles.

[karimwassef]

After looking at these different techniques, I'm changing the build method from all glass to hybrid.

The bottom is very large 9' x 8' and I would like it to be solid enough to support my weight walking in as needed.

I also have more experience with plywood tank building.

The base was always intended to be wood studs with a 3/4" plywood top.

So I'm changing the bottom from flat glass to a multi-layer 3/4" plywood with epoxy -OR- 3/4" PVC sheet or board. The bottom is made up of two sheets creating a 3/4" base first.

Then the sides will also be the 3/4" vertical sheets (originally part of the base only) creating a 2" lip all the way around. The plywood sides will still go all the way to the floor.

Then a smaller 3/4" plywood sheet (3/4" from the sides and 1" from the back wall) inside to create a groove between the outside lip and the inside stack. I might double this up to make it 1.5" inside and 2" outside.

This should create a stable base for the glass to slide into like a frame.

If plywood, then I'll use the epoxy to seal. If PVC, it should be sturdy enough as is.

Overall I think this will be more structurally solid and cheaper.

[karimwassef]

I don't expect the silicone in the bottom to be functioning as an adhesive. The structural integrity is provided by the "glass in groove" 1.5" pocket.

The silicone will be creating a seal against the pocket with the pressure from the glass weight and the water pressure against the wood or PVC.

The glass to glass will be clear silicone with the gap method.

I haven't decided on whether this design needs eurobracing on the bottom...?

The top will remain a double stack of 3/4" eurobrace at 4" wide.

[Diokhan]

Some of these build techniques may help what you're after. This guy uses the bottom lip as a clamp while he builds.

You may have better luck and might find it cheaper to use 1 pvc sheet for the bottom than using epoxy coated pvc. You can always add plywood as an underlayment depending on how you have your stand. I would use a strong solvent like Weldon 711 vs the Oatey stuff to chemically bond the two pvc panels together for the bottom. I'd look into something like Dow 795 to seal it.

[karimwassef]

yes. That's the direction I'm going.

[karimwassef]

here's the walk through:

[karimwassef]

and here's the closeup of the edge grooves

[karimwassef]

basically, the tank and its base are one piece. At this scale, I don't expect there is a need for the two to be separate or separable.

[karimwassef]

I like his technique in not permanently fastening the side plywood until after the glass is seated, then using the plywood there to clamp the glass in place.

He doesn't use the side plywood as a window edge though. I plan on applying silicone between the glass and the side wood lip to seal.

I can still keep the wood loose and tighten afterwards. Using the "gap method", this should be pretty straightforward since the different sections can be "seated" in the gap on the bottom with the sides intentionally gapped. Then the sides can be siliconed to each other.

[karimwassef]

I realize that if the wood is epoxy coated and I use the gap method, the actual dimensions of the wood and glass will change to account for the gap spacings. I just don't know what that gap needs to be yet.

I'll assume a 1/8" epoxy thickness and 1/8" silicone gap for now.

[karimwassef]

I thought for sure that someone would offer up a definitive guide to building large glass tanks?

Are you all really going to let me do this without advice?

[karimwassef]

For the sake of completeness

I did consider construction UV for glass last year but never had the time to run the testing

http://www.crlaurence.com/adv/catalo.../zips/gb10.pdf

http://www.reefcentral.com/forums/sh....php?t=2562238

I am wondering if using the UV cure CRL UV770 wouldn't be a good option for the very top of the glass-glass interface. I'm thinking of something like a spot weld section at the very top to minimize the need for the top eurobrace.

The idea is that the two 2" of the tank are usually not subject to water pressure like the bottom of the tank.

I can minimize the bottom eurobrace by using the plywood/epoxy groove structure.

I can likewise minimize the top eurobrace by using a splot-weld UV glass adhesive.

I guess that would make this a hybrid plywood glass hybrid silicone UV epoxy tank.

Thoughts?