DeVitaf
Member (Sr. Member)
Posts: 862
From: Boston, MA
Registered: APR 2002
posted July 18, 2002 06:58 PM
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Drilling Glass...
I saw a tank today with sump returns up through the bottom of the tank. Is it very difficult to drill glass (if it's not tempered)? Should it be done by a professional? Does it structually weaken the tank?

Thanks.



slipknottin
Moderator (Moderator)
Posts: 4975
From: new britain, CT
Registered: JAN 2002
posted July 18, 2002 07:06 PM
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haha, just my kind of question
drilling glass is actually pretty simple and straightforward. it does take a great deal of patience, so if you dont have that, it might be best to have a glass shop do it.

however, you can order the bits from www.ameriglas.com. before you order bits, i suggest you taking a trip over to www.savko.com and checking out what size bulkheads you would need to plumb it. all the bulkheads will tell you the size of the hole they need, and you can then buy the corresponding bit or slightly larger.

the reason i say it takes some patience is the actual process itself. because of how it makes the hole, it doesnt actually drill, it grinds the glass down. you need to stop every couple of seconds, and spin the bit in a cup of water to dislodge all the glass pieces stuck in it, and you need to keep the hole reasonably wet to help the bit work. you also need to keep the bit rotating very slowly. (you can use a hand drill, this is what i used and it worked fine.( it took me about 25 minutes to drill each hole on the tank im currently working on.

all that being said, if this sounds like something you want to attempt, the process is fairly easy, and ill help with any specifics you want. just remember, make absolute 100% sure that what your drilling is NOT tempered glass. you drill tempered glass and it shatters.

[This message has been edited by slipknottin (edited July 18, 2002).]



DeVitaf
Member (Sr. Member)
Posts: 862
From: Boston, MA
Registered: APR 2002
posted July 19, 2002 07:15 AM
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I am very nervous about drilling glass. Especially on a $400.00 tank.
This may sound like a stupid question but here goes,
How fragile is the glass? I mean will it break very easily if you don't do this right? Is it prone to cracking while drilling if you go too fast or at the wrong RPM? If I screw this up there is no repairing the tank .



DeVitaf
Member (Sr. Member)
Posts: 862
From: Boston, MA
Registered: APR 2002
posted July 19, 2002 07:18 AM
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Follow up, out of curiosity how would you put a hole in tempered glass? Or would you?


slipknottin
Moderator (Moderator)
Posts: 4975
From: new britain, CT
Registered: JAN 2002
posted July 19, 2002 09:50 AM
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i dont think glass is all that fragile at all, the only tanks i have seen crack happened for one of the following reasons
1. they used a drill press and pushed down too hard

2. it was a very small tank (10 gallons) and they pushed too hard with a hand drill

3. they tightened the bulkhead too much (your supposed to go one turn past hand tight)

4. they put a piece of hard PVC from the bulkhead and forgot it was their, then they moved the tank and the PVC and bulkhead snapped the glass

other than that i dont believe ive ever seen glass break under drilling


AGA and other aquarium manufacturers that have drilled glass thats tempered actually drill the holes first, then they send the glass out to be tempered.

there is no way to drill tempered glass. if you try it the entire piece shatters.