Glass cuts

[Steve-O-]

So i want to create my new tank before i do so just want to ask people who have built there own tanks about glass cuts.
I will be getting the glass company to cut it and drill but i will put it together with my jig i made for it.

My tank will be made from 1/4in glass

16H-20W-20L

so would my cuts be like this
Sides 19 1/2 W - 16H
Front & Back 20 x 16
Base 20 x 20

Now i know sitting on the base would make it 16 1/4 tall that is ok with me. But do i take off 1/4 of each side or is it like 1/4 and 1/16 for silicone

[The Grizz]

You dont want the sides sitting on top of the bottom piece of glass you want a floating bottom. If you want 20 x 20 ID you need sides to be 20 1/8 x 16 (+ thickness of bottom) front and back 20 1/8 (+2x thickness of sides) 16 (+thickness of base)

[Steve-O-]

Oh i was going from this site
http://saltaquarium.about.com/od/diytanksrefugiums/ss/diyaquarium.htm

Said to place your glass ontop where does the 1/8 come from just curious all new to me.

[The Grizz]

I read the whole thing & it said onto not on top. When putting say the back piece on you silicone the edge of the bottom pane, then align the back piece with it leaning back at an angle, as you bring them together you tilt the back piece upwards to make it 90 degrees to the bottom.

When you build a tank you want to have 1/16" of silicone in-between every piec of glass.

[Steve-O-]

hmm i saw this
We have always constructed our aquariums with the two end pieces of glass fit inside of the back and front panes, and the front, back, and two side panels set on top of the bottom base pane of glass.


But thanks for your help i will do it the way you said. :biggrin:

[Aquarium_Medics]

I read it as the 4 sides are on top of the bottom also, However, I also agree with Grizz. Any tank i have taken apart to reseal, have had the bottom inside the side panes.

[Steve-O-]

Ya that is why i asked just to be sure so thank you guys for your help

[KrazyKuch]

I have a 180 that i made myself sitting on the bottom, and its been fine for 4 years...you can do it either way really, I personally would rather have the seams holding back just water instead of holding back everything!

[LeeR]

it just looks better if the sides are wrapped around the bottom. I've built both and they both work fine one just looks nicer.

[Ross]

The reason to have the bottom floating is that silicone is far superior in tension than it is in shear. A small nick in a seam, can fail catastrophically if it's not in tension.

That being said, I have a 20"Wide x 20"Tall x 7" Thick that is sitting on the bottom pane of glass for over 3 years without any issues.

[The Grizz]

With the side glass on top of the base glass all it takes is your stand to be a little wonky and the bottom is sure to crack. Even the cheap Hagen tanks are footing bottom when you take the trip off. I have had a couple tank built with not a floating bottom & both have cracked shortly after being set-up. ( I didn't build them )

If you post exactly the inside dimensions you want I can tell you what sie to get your glass cut & I would suggest to go with 10mm glass it is much nicer to work with and looks great.

[ScubaSteve]

Ross hit the reason right on the head. I can be done either way but a floating glass pane is superior. If you give day or two I'll put together a tank building tutorial. It's something I've been meaning to do for a while. This will give me an excuse. I called on several professional tank builders to answer questions, so this isn't me preaching but passing on what I've learned over the past two months.

[Steve-O-]

Cool thanks guys for all the info on this.

[Steve-O-]

Still waiting on my glass, Again big thanks to grizz for all the calculations and Scuba for the overflow directions.

My glass company phoned me today and decided to tell me that my tank will Blow out if i do not use tempered glass. I of course just told them no it wont its 3/8 glass with euro brace. So what do you tank builders think of what they told me. they tryed and tryed to talk me out of it.

[The Grizz]

Just tell them you do not want tempered glass & not to worry about what you are building. Being 20" x 16" it could have been made out of 1/4" glass & still would not blow out, so being 3/8" it will be just fine as long as you get it sealed right.

[Steve-O-]

Ya scuba said 3/8 is 9x saftey factor and 1/4 still would have 4x safety factor. Just kinda made me mad.

[The Grizz]

When I order glass from a glass shop I don't tell them what I'm doing with it, there not tank builders & have no idea what the hell there talking about. Only a glass shop that actually builds tanks have a clue.

[Ross]

Ya scuba said 3/8 is 9x saftey factor and 1/4 still would have 4x safety factor. Just kinda made me mad.

My 6mm (1/4inch) tank is 20x20 and its holding up fine...

Do at Grizz sayes and dont tell them what its for.
I've heard of places wanting wavers signed for liability reasons.

[CherylMcKay]

I would love to read your guide. I live up north and shipping is killing me but I want a bigger tank. Starting my research to see if this is the way to go.

[StirCrazy]

hmmm a weird things in this thread. first is if the bottom is floating then it is in shear and tension, unless the bottom is fully supported.. then like was mentioned you better have a good stand or something to make up any unevenness.

I have 4 tanks in the garage and I just went and checked them.. all 4 are built with the sides on the bottom, and the 25 I redid 4 years ago had the sides ontop of the bottom.

My 33 was the other way around but it had a plastic moulding that suported the bottom and the sides, but my custom made 94 gal had the same moulding but the sides were ontop of the bottom....

as long as you suport the tank properly for the method you use it doesn't matter which way you build it.

the shear strenght for the silicone we use far exceeds anything well ever subject it to. now maybe if you build extreamly tall tank it would be different but you would also be looking at more than silicone to support the bottom edge.

Steve

[Steve-O-]

OK have my glass here. So i will make a writeup from start to finish inc the bean overflow build. I could be wrong in some area's of my documentation but will have you guys to help make it proper. Also again thanks for the help

[Steve-O-]

ok wanted to start and tape the glass. Was gonna run green tape over each pane to make nice even silicone lines.

So is 1/4in a good line on each pane or should i go bigger?

here is a example of my bottom pane i taped.
http://www.bcinteriorreef.com/pictures/bottom.JPG

[ScubaSteve]

ok wanted to start and tape the glass. Was gonna run green tape over each pane to make nice even silicone lines.

So is 1/4in a good line on each pane or should i go bigger?

Depends which panel you are taping. If it's an piece that has other glass butting up to it like all around the front and back panels or the bottom edges of the sides, you'll need to tape for the thickness of the glass then add a bit more. Personally I left 1/8" seams. So some edges where taped at 1/8" and some were taped at 1/2", depending which edge was butting up to what. For the bottom is doesn't matter because you're not going to see it but I still taped mine for 1/8" because... well... I'm an anal-retentive perfectionist.

Bit of a detail note: try to make little tabs at the end of the tape for you to grab on to. It doesn't seem sticky now but once it's been on there for a bit that green stuff can stick pretty good and once everything is all gooey and covered with silicone it can be a pain in the ass to remove the tape and still keep things looking nice.

[Funky_Fish14]

Tanks built with 1-piece trim, like say a hagen, oceanic, perfecto, or all-glass tank, will have the front, back, and sides, resting on top of the bottom pane of glass. (there may be some exceptions with shape tanks or drilled tanks, but im referring to 'boxes').

Uneveness can definitely cause cracking in any build type or fasion. It is always best to make sure you have a proper installation surface anyways.

When building your own tank... any custom tanks I have built myself or have seen built at the glass/tank shop I worked at, or ordered myself from other builders, always have the sides, front and back, around the bottom piece. Even if you are adding trim after, if its cut-to fit trim, I still recommend going around the bottom.

[lastlight]

All the custom tanks I've had made were done with sides around the bottom as well. I helped hoist the 3/4" glass into place. I think had that been installed on top of the bottom... well all the silicone would have squeezed right out under the weight of itself!

[Steve-O-]

Ya scuba i was gonna add the extra amount on the sides also with easy pull off tape thanks for your help yet again. Any my surface is 100% true