I'm Gonna Do It!!!! Drill!!!

[sumphead]

OK the only thing that can stop me now is a stern warning from my friends here on AA. I'm going to drill my 72G Bow. I contacted all glass and made SURE only the bottom was tempered. I got a circle glass cutter. WISH ME LUCK!

Now for the ???

-is an inch and a half too big or big enough (i plan two holes drain and return)

-anyone know the [acronym:1237411364="Gallons per hour"]GPH[/acronym:1237411364] flow through that?

-would you go 1" to ensure stabilty of the back wall?

waiting patiently
R-

[peterp]

Oh man that is scarryyyyyy

I'd head over to a large fs with a small tape meassure and see if I could get some measurements of one of their pre-drilled tanks if they have any

I've been over to mine a few times to measure tank sizes & stand & hood & lighting sizes for a planned "future" installation.
They don't seem to mind so long as you don't start disassembling things in the store.

[fishfreek]

Do you know what size of bulkhead you intend to put in those holes? That will govern how big the hole needs to be.

For example according to the bulkheads that marinedepot.com sells a 1" bulkhead needs a 1 3/4" hole. A 3/4" bulkhead needs a 1 1/2" hole.

http://www.marinedepot.com/a_ft_2.asp?CartId=#bh

See above link for more information.

Good luck in cutting the glass on the 75 [acronym:a6c28cc452="Gallon"]gal[/acronym:a6c28cc452] that must be close to 1/2 if not 3/4" thick with a scoring style glass cutter.

Do you intend to have two drains? Do you intend to have holes for your return or do you plan on plumbing your return above the tank.

It sounds like you might need to plan this out a little more first. How are you going to keep fish from getting taken into the drain lines? WIll you use a simple screen or cone over the hole or will you do an internal overflow with acrylic?

[alrmc4]

good luck my fingers and toes are crossed for you

[sumphead]

Thanks so much guys. I am planning and planning and planning...

...I want at least a one inch bulkhead. I plan on converting a cone off of a pengiun 330 to prevent suckage (hehehe) of critters. a returm hole as well.

it seems to be a 1/4 inch thick glass. i also plan on placing a piece of 1/8 plexi as a buffer under the fitting against the glass.. sound good?

R-

[sumphead]

Saturday morning bump! Need all the help I can get. And now placing on hold until I've seen a 48" dank with the back drilled.

[justDIY]

ok, so this hole - how are you making it again?

are you using a water-cooled diamond+carbide drill bit?

[sumphead]

No, it's actually a circle class cutter. It can be attached one of two ways; either drill a miniscule hole with a diamond tip on a dremel or with a small tight suction cup. It has an arm on a swivel that rotates 360 around the central pivot with an extendable diamond cutter. Set it up and spin it 'till it cuts through. I ran a trial on a relatively thin piece of glass from an old picture frame. Cut like buttah' perfect circle. As for the bracing I mentioned I intend if all goes well to support the entire back wall (decision after embracing fear) with 1/8 plexi and attach it with silicone and under the bulkhead.

Still pondering...

Thanks yet again,
R-

As for the bracing I mentioned I intend if all goes well to support the entire back wall (decision after embracing fear) with 1/8 plexi and attach it with silicone and under the bulkhead.

Bracing What? I don't understand, Are you talking about as you cut the hole? or after... If after, I would say definately overkill.. It will be just as strong cut as it would be whole..

[peterp]

The more I thnk about it, [acronym:24cf6195bc="In My Honest Opinion"]IMHO[/acronym:24cf6195bc] I think you would be much better off to take the tank to a aquarium shop that has the proper tools to drill glass. They will charge a bit but a lot less than a new 72 [acronym:24cf6195bc="Gallon"]gal[/acronym:24cf6195bc] bowfront.

We cut a lot of glass but it is all straight cuts, you put the glass in the Fletcher cutter pull the handle across the glass to score it and wack the side you don't want to keep.
The thought to scoring a tank bottom and trying to wack the little circle scares me quite a bit. Cuts are usually predictable but sometimes the wrong side fractures into little pieces and that would totally ruin the tank.

Also from what I have seen glass likes to break along mostly straight lines, if the break dosen't follow your score and heads off on its own....

I agree with JustDYI, if you don't have the proper large 1-1/2 or 2 inch cooled diamond+carbide bit don't try it.