i want comments on a diy plywood build

[john73738]

They say exterior, but I am using 3/4" 7 ply cabinet grade. I have seen some that use hardwood ply, It just depends on how you want to finish the exterior of the tank. I want to stain rather than paint so I needed the better plywood (and I got it on sale for $22 a sheet)

Your design would just be sexy Cant wait to see you get started..

Bear

 

[xdragonxb0i]

They say exterior, but I am using 3/4" 7 ply cabinet grade. I have seen some that use hardwood ply, It just depends on how you want to finish the exterior of the tank. I want to stain rather than paint so I needed the better plywood (and I got it on sale for $22 a sheet)

Your design would just be sexy Cant wait to see you get started..

Bear

thank you. Now that i have figure out how to build it structure. My original picture would not allow me to fit two side view panels on the left side.

so here my new design. it would be 10x48x26. Although garf dont recommend building anything over 96'', if i can find a solid 10 foot plywood. i dont see why i cant build it. i realy want to keep the left viewing panel. and i dont think it would look good a window on the right end.

I already have the glass, which is the main cost of the build. Only thing stopping me is lazyness, its a PITA to take apart a large tank

 

[john73738]

That is still a pretty sexy design, however going beyond the standard 8' plywood I personally would get into the design similar to this...

http://www.monsterfishkeepers.com/forums/showthread.php?t=305927

By Badoleross.

when you get to that level trusting butt jointed plywood to hold back 650ish gallons of water. Now you are getting to another level of building. Look at many different designs, and construction methods. And post pics while you build that monster.

Bear

 

[xdragonxb0i]

i hate to use, the termm "in theory" It should hold, because it contain the same amout of Pressure per squar inch.

i would really love to copy greenterra design. But i am inexpereince with the use of fiberglass.

http://www.monsterfishkeepers.com/forums/showthread.php?t=254175



Its just a though. but i wonder if anyone tried to use rhino lining on a plywood tank.

 

[CJH]

Its just a though. but i wonder if anyone tried to use rhino lining on a plywood tank.

Rhino Lining and other truck bed liners have been used. Very expensive but they do work. They do present problems with glass adhesion as silicone does not bond to it well, which is one of the characteristics which makes them so desireable as truck bed liners.

If you want to use truck bed liner or anyting with similar chemistry then you need to attach the glass first. Personally I would get a small kit of epoxy or polyester and paint a small 2" strip on the wood where the glass will be attached. Then I would use a moisture cure polyurethane caulk to attach the glass to this resin covered area. Once the polyurethane caulk was fully cured I would then have the bed liner sprayed, including a slight overlap onto the glass.

Very similar to what RedO did with his polyurea sealed tank. But I would take it a step further and seal a small section of the wood with resin first and would use polyurethane instead of silicone.

[EDIT] FWIW, one of the international distributors of Pond Coat recommended basically exactly what I suggested above but said to use polyurethane to attach the glass or acrylic directly to the wood. I recommend the resin as an additional step and because it's easy to get in small kits.

 

[john73738]

I am looking to use Sherwin Williams Macropoxy. It just paints on, and you can use glass cloth to reinforce the seams. Fiberglassing I agree is a daunting task to me because I have never done it. But a friend of mine that is a glasser, and has worked professionally in the epoxy biz told me that the plywood if the strength, so the fiberglass cloth over all is not necessary. So you will just epoxy as if you are painting the wood. Not difficult. (We'll see)

 

[CJH]

A friend of mine that is a glasser, and has worked professionally in the epoxy biz told me that the plywood if the strength, so the fiberglass cloth over all is not necessary.

I agree with your friend... fiberglass really is not needed for strength in an epoxy sealed tank. But there are two other reasons that I can think of to use fiberglass.

One is if you're using a cheaper polyester which will not flex as much as a 3/4" plywood tank filled to a 24" depth.

The second is less important but glassing can help avoid putting stress on the glass which even with a thick silicone joint will not flex as much as plywood. So glassing can help avoid stressing that joint

But in both cases there are other ways around dealing with the flex.

And contrary to popular belief, epoxy resin and epoxy paints are more than flexible enough to be used in plywood tanks. I know there is one epoxy product that has not worked well but this should not be used to characterize all epoxy resins and epoxy paints.

 

[john73738]

Gonna get my friend's opinion on the macropoxy. Will post his opinions in my 250g thread in my sig line.

 

[xdragonxb0i]

So I'm thinking about glueing and screwing in the walls and add support around the frame.

And avoid fiberglass. Since you guys say that fiberglass isn't a nesscary reinforcment

From what I read padrmi pond coat is flexible and is fairly strong

 

[xdragonxb0i]

bump. What do you guys think.
The purple is plywood, and the "metal looking walls" are plywood.

the design is a plywood box, but has been reinforced. Im thinking this will work just as well as a tank like greenterra, minus fiber glassing and thicker wood. The only thing that i consider a possible problem is that the screws will be holding the wall together, and the water would be pushing it out. But the plywood box design, rely on the same principals.

(i dont understand what people mean, when they say dont put any pressure on a screw)

but any who, I would build the box, out of 2x4, and then apply 1/2'' plywood on the outside of this frame. After that i would apply Pond coat, and lay the glass.

Tank would be 120x48x27

i have 4 panes of glass, 1 i might not use because if large chips
1- 90x24x.5
3- 23x24x.5

http://img.photobucket.com/albums/v606/skylinexk1ng/photo-5.jpg