2 piece tank ideas

[dawnmarie]

I don't have a 100% clear picture in my mind but I do not see why the metal cannot be sandwiched between plywood and only structuraly supported to the outer layer... (In other words Sheet the metal on the inside) Then you should be able to seal the slight gap with silicone...

Why can't the pond coat , or whatever, go over metal ?
The problem (if there is one) is if the fasteners coming through the plywood are only supported on one end. The plywood doesn't count structurally and the fasteners are prone to shearing, IE single shear. I also feel the clamping action of a plate on both sides would be bulletproof.
I have been known to "over engineer" stuff so take this with a grain of salt.

 

[Satan's Goldfish]

I think the biggest problem with the flat idea is that the bolts go from inside the water to outside the water, and the best way to get that water tight would be for each half of the tank to be metal and the holes going through to be threaded, to the bolt size, and the bolt threads covered in PTFE tape to make sure each hole is 100% properly sealed.

I have seen a large water tank built out of metal and is fish safe as long as it's well coated in a pond coat or some such compound. I'd trust metal a hell of a lot more than plywood for joing something like this together.

Using the flange idea with the bolts going horizontally through the outside, if the flange was made out of a good metal angle then i'd trust it not to bend under the water pressure. I built a TV table out of 50mmx50mmx3mm thick 90 degree steel angle all held together by m12 bolts a while ago. Yes it's heavy, but it would probably be able to hold a couple of tons of weight if the metal frame holding up my 6x2x2 is anything to go by. It's a hell of a lot stronger and less flexible than anything similar built out of wood would be and the forces required to start bending that 90 degree angle out if it's bolted at regular intervals would have to be absolutley massive

 

[dawnmarie]

Using the flange idea with the bolts going horizontally through the outside, if the flange was made out of a good metal angle then i'd trust it not to bend under the water pressure.

I like this idea, I just can't visualize how the plywood tank bottom is going to be attached to the angle iron effectively without exposed fasteners.

If you mean to construct the entire bottom of the tank in steel then just have the supplier brake (bend) a 90 degree x 1 1/2" lip on both halves. The more I think about it the more I prefer this idea.

 

[Satan's Goldfish]

I like this idea, I just can't visualize how the plywood tank bottom is going to be attached to the angle iron effectively without exposed fasteners.

If you mean to construct the entire bottom of the tank in steel then just have the supplier brake (bend) a 90 degree x 1 1/2" lip on both halves. The more I think about it the more I prefer this idea.

That looks like what i was thinking. I'd go all metal if it was me too, but even using what you've drawn there the ply could be fitted above the metal flange and a lot of screws sunk through the metal into the wood in a staggered pattern at various distances from the join. If it has a 2x4 frame for strength then it'd probably be better screwing to that than just onto the ply as you'd then be able to get larger screws in deeper. Cover both halves of metal and wood in pond sealant before bolting then together. Only difference from what you've drawn is i'd have a rubber gasket between the flanges to help with sealing and distributing pressure when the bolts are torqued up. Caulk would be optional then too.

 

[I<3fish]

Why not just build two tanks-or build one tank that is as wide as your tallest exit door? Seems much cheaper, easier, seems like there would be less problems that would arise, ect. And if you're worried about losing gallons, make it taller.

 

[redman88]

8'x8'x2' turned the right direction would go through a door, then you just make a stand that could be bolted together and no need to worry about water leaks...........nvm i thought about that some more. just shorten a side down to the hight of the shortest door and problem solved

 

[I<3fish]

8'x8'x2' turned the right direction would go through a door, then you just make a stand that could be bolted together and no need to worry about water leaks...........nvm i thought about that some more. just shorten a side down to the hight of the shortest door and problem solved

how original... Oh wait, look up one post... lol.

 

[The1and only]

Standard front door is 6'8" tall and 34" wide some 36 so take off 2 inches for play and you still have a 8x6'6"x2'6" tank which would be just under 1000 gallons. that is a pretty big tank that can still be moved with relative ease.

 

[Just Toby]

Standard front door is 6'8" tall and 34" wide some 36 so take off 2 inches for play and you still have a 8x6'6"x2'6" tank which would be just under 1000 gallons. that is a pretty big tank that can still be moved with relative ease.

I hope you do not get flamed by the post above LOL

 

[I<3fish]

I hope you do not get flamed by the post above LOL

This guy gave good info; the only reason I "flamed" the post below me was because it was the EXACT thing I had said.