Should I be worried about drilling 3/4" glass?

[Peter Eichler]

I've drilled tanks before, but never anything as thick as 3/4". Should I be more worried about drilling a tank this thick or am I being silly? I have a drill guide and the proper diamond hole saws. I think most of my concern involves cracking a tank that costs $1000+ as compared to other tanks I've drilled that are much cheaper.

Thanks for any help!

[hobogato]

i have found that thinner glass cracks easier than thick.

[Peter Eichler]

Yeah, the only tank I've ever cracked when drilling was a 10 gal., and that's probably because I was doing a bunch of them and going too fast. Still, it freaks me out a little to be drilling into something that's going to cost so much.

[hobogato]

i know the feeling. of all the tanks i have drilled, i have only cracked one tank that wasnt a 10 or 20 gallon (only cracked three of those), and it was a very old 60 gallon cube.

still, i know what you mean - always makes me nervous too(especially the really big ones :) )

[rguyler]

I agree to what's already been said. You would be hard pressed to break 3/4" glass...it's pretty tough stuff. Vibration kills though so just be sure to brace everything nice and solid and keep the drill and glass well lubricated. I use a mixture of antifreeze and water.

[scaryperson27]

I don't see the point of using Anti-Freeze. It's a lubricant, so it would take the roughness away from the bit wouldn't it?

[hllywd]

This debate comes back every couple of weeks or so in the DIY forum. Water, vegetable oil, mineral oil, antifreeze, etc... Essentially water serves as a lubricant in this application, it also cools. Anything else is a waste of money and creates various issues from being a big mess to being potentially poisonous/hazardous/dangerous... Stick with plain old ordinary H2O. With H2O you end up with silica sand, and, well... H2O. With antifreeze you end up with a puddle that will kill your dog, or at least be environmentally irresponsible. Oil leaves a goopy mess...

Drill the 3/4" like any other glass go slow and keep the saw wet with a constant drip of water, the whole job even in 3/4" glass shouldn't take more than a pint or so, if you build a dam even less. support the backside to prevent it from chipping when the saw breaks through and you should face few if and difficulties.

[Peter Eichler]

Thanks guys, I think I just needed a little encouragement to stop being such a pansy :lol:

[scaryperson27]

The profanity filter is in place for a reason, please do not alter words to get around it.

Thank you

[rguyler]

Scaryperson, the lubricant is an advantage as it reduces friction, therefore reducing heat, which can shorten the life of your drill. It does not cause the drill to grind the glass any less efficiently.

If hllywd chooses to knock my opinion then that is okay with me. He obviously feels passionate about not allowing his dog to lick up his drill mess. I personally find that there are much more toxic substances in my home than antifreeze and I am responsible enough to not allow my animals to lick them up. Besides, the noise of drilling glass is enough to keep the dog hidden under the bed and the cat firmly attached to the ceiling so for me, the benefit of the lubrication (over plain water) outweighs the potential hazards.

[hllywd]

http://reefcentral.com/forums/showthread.php?threadid=1048010&highlight=antifreeze

[scaryperson27]

But the drill uses friction to cut the glass. Why would you want to reduce it?

[scaryperson27]

Also, we aren't even using antifreeze for it's soul purpose. It is used to change waters boiling point, and to KILL INHABITANTS like algae. If you are looking to use something to lubricate, then you should look towards a light oil that is pure so that you can use it and not be afraid of it killing off a reef.

[rguyler]

That thread has no more basis of fact than this one but I digress.

My original post was an opinion based on 25 years of glass drilling. Read it again and you will find I didn't even suggest the use of antifreeze, merely provided some encouragement to the original poster.

Everybody reading this may choose their own method of cooling and I make no bold proclamation that one method is more or less correct than my own.

[scaryperson27]

I'm not trying to shut you out, or discredit your 25 years of experience glass drilling. I'm interested in a discussion. I would rather my opinion be shot down to better understand how your method works. Where exactly does the lubricant reduce the friction?

[rguyler]

That's how lubricants work in a general sense. Reduce heat-causing friction which in turn cools. There are also conductive qualities depending on the medium in question. I find ethylene glycol to work better than water in my experience.

[hllywd]

Peter Eichler, Sorry this took a tangent. You shouldn't have any difficulty with the 3/4" tank if you're confident with thinner tanks. Just use the same methods you have before and take all the standard precautions.

[hllywd]

unsubscribed.

[coralnut99]

The only thing I can add here is to reinforce the suggestion to reinforce. 3/4" is pretty tough to crack as mentioned. The thing to keep in mind is that it's gonna take quite a bit longer to get through the stuff. So patience at the very end of the hole, and reinforcement at the back side of it are pretty much the keys to success here. Fwiw, I've used both antifreeze and water, and saw no benefit to antifreeze, so I now just stick to water simply because it's just a snap to clean up by comparison.