Plywood Tank project. Jr. MFK

[salty joe]

Dont use gorilla glue near anything you like or dont want ruined
(hmmm nice hardwood's) idiot

A famous furniture maker, Maloof I think, tested Gorilla glue against good wood glue, Franklin I think. He gave the glued wood pieces hell and the Gorilla glue failed way before the wood glue did. I'm sure Gorilla is great for some projects, maybe not so much for gluing wood together.

 

[salty joe]

Did you glue those joints as well as screw it together? If not, I think it would be a good idea. Also, I've seen 2x2s screwed & glued to all inside corners. Looks good practice to me.

18" of water on a 96" span supported by a single 3/4" plywood might work with a euro-brace as well as a center brace.

 

[Bud8Fan]

Looks bulletproof to me!

 

[AttackFish]

lol, but this is a tank!!!!! and you guys need to get over yourselfs, because this will work


screw dovetails when you have 20 screws

This is not going to work, how are you going to brace the front so that it doesnt bow?

I think you should turn it into a turtle pond. IMO, this will not hold water as a tank.

 

[Bud8Fan]

He's talking about the corners not the bracing. He is actually asking for ideas on bracing.

 

[cvermeulen]

what you have now wont support ****

Spoken like a well educated engineer, no doubt.

What you have now will be fine for not flying apart, but it'll bow. I'd add braces like has been suggested, either screw 2x4's lengthwise along the top of both long sides, or else add a top piece that has cross braces. Don't waste your time bracing the corners, unless you just want to for your own creative benefit. You're absolutely right that you're better off doing any fiberglassing before you put any supports in the way... but I'd also like to say that the fiberglass is not a requirement, and it will complicate the build significantly. A few coats of epoxy, or gelcoat, or MFK Vetted your sealant of choice will be fine. I skimmed through this thread, so maybe I missed it, but how are you planning to work your window? 2 short ones, or one longer one? If doing 2 short ones, I'd suggest screwing a 2x4 in, standing upright between the windows, and then screwing your top piece to this 2x4 when it goes on... 2-pane fronts always seem like they're gonna blowout in the middle to me for some reason.... whatever you do, if you're gonna add any bracing inside the tank near or under the waterline, do it before you start applying your sealing.

 

[cvermeulen]

A famous furniture maker, Maloof I think, tested Gorilla glue against good wood glue, Franklin I think. He gave the glued wood pieces hell and the Gorilla glue failed way before the wood glue did. I'm sure Gorilla is great for some projects, maybe not so much for gluing wood together.

Gorilla glue is waterproof though... a nice selling feature. It does foam though, which sucks unless you're filling gaps with it. Epoxy is your best bet if you really wanna go nuts... but with a screw every 2" like he has, glue is just icing on the cake anyway.

 

[cvermeulen]

This is not going to work, how are you going to brace the front so that it doesnt bow?

I think you should turn it into a turtle pond. IMO, this will not hold water as a tank.

I'd like to know what you're basing that on? Did you guys all miss the 700gal build someone did with coffee table tops and NO corner bracing at all, just 2.5" deck screws driven into end grain? Did you realise that a 2.5" screw, driven into the edge of 3/4" plywood has a pull-out strength of something like 1500lbs? One screw. This tank has about 300 screws holding it together, so unless it's being filled with mercury, it oughta be fine.

 

[cvermeulen]

Also, instead of using butt-joints to connect each corner, you should have used dowel reinforced butt-joints wich would be much stronger.

Dovetail joints would have been good aswell.
Pictures included of both joints.

Right because drilling a 3/8" hole 3/8" away from the edge of a chunk of plywood (which is what you'd be doing, think about it a bit, draw a picture) is going to make a great joint. Plywood is also the perfect material for dovetails in your world too I guess?? Have you ever built anything?

 

[basslover34]

Going to have to Agree with Cvermeulen on these Points and say to all those haters on this thread that


Add some bracing to the inside top and you'll be fine if you want to go one step further you could add a frame all the way around the inside using 2x2's it's not a huge tank so I wouldn't go any more than that as you'll be giving up space which goes against everything we MFKer's believe in