Drilling Glass for Closed Loop: Part I

[Matt L.]

I am gearing up to drill my 90gal AGA tank for a closed loop, however, I need help! Can someone please give me advice???

I am fairly confident in what I need to do to drill the glass. I have acquired the diamond hole saws from AmeriGlass. I have duly read the old thread back on RC, and know how to set up a dam out of modeling clay to keep the drill bits and glass bathed in water during the drilling process. Finally, I have read the maximum drilling speed information on the AmeriGlass web site. For hole saws of my size (1.5" and 1.75" for 0.75" and 1" bulkheads), a speed between 150 and 300rpm is recommended, being closer to 150rpm.

However...

I have one lingering question I cannot resolve on my own: how do I go about drilling the holes? More specifically, what type of power drill would I use to generate a specific speed? I went to Home Depot (first mistake) and asked them if they carry a power drill where you can set the maximum speed. They claimed to have no such drill. I have a power drill with the traditional trigger, but I am afraid to use it, as I have no idea what speed I am generating, and fear that while holding it in place for the n minutes it will take to drill through the 3/8" thick glass, the speed may increase to a dangerous level, and once I crack the glass, it is all over. I noticed that Home Depot did have a few cordless drills for sale where the maximum speed wasn't much greater than a few hundred rpm, but still, how would I make sure I'm not drilling over the 150 to 300rpm speed? Its hard to look at a rotating drill bit and tell. Therefore, I ask: what type of power drill did you use to drill your glass?

Matt

 

[Ray]

You can set the speed on a dremel

 

[Matt L.]

At Home Depot, I had thought about using my dremel, but I: a) didn't think the dremel was powerful enough to drive such a large diameter hole saw (1.5" or 1.75" in diameter) through glass, or b) could accept such a large bit (the part that goes into the drill is 5/16" in diameter)? Also, I thought the speeds on the Dremel were all much higher than 150rpm. If you did use the dremel to power a hole saw, please let me know what type of adapter you used, and what speed setting,

Matt

 

[mapster]

I used a power drill with 2 settings, one for high speed drilling and one for low speed drilling. This is not uncommon with power drills. I used the low speed setting with the trigger fully depressed.

The speed is not the most important thing, keeping the drill level is. The suggested bit speed is mostly to maximize the life of the bit. My best advice is to buy and use a drill press. In my experience (I didn't use a drill press) the most challenging part of the whole thing is getting the hole started. Without the drill press it was nearly inpossible to keep the drill steady to start the hole and the result was chipping. Another problem I had was keeping the drill level, on little slip and the bit will snag and you will either break the glass or break your wrist. My bit snagged a few times, not bad enogh to cause damage to me or the tank but enough to crap my pants. A drill press will make the job so much easier and you wont have these problems.

Be prepared, with these bits it takes a long, long time to drill the hole. I had to start and stop a bunch of times. All in all it took me a week to drill three holes. I wanted four but was so sick of drilling after three there was no way I would drill another. The drill press will take the fatigue of holding a drill steady for 3 hours and will make the job so much easier and faster.

I used play-do to create the water dam, worked well. Its a nerve racking experience, I wish you the best of luck.

Oh yeah, tape of one kind or another (I used painters tape), one both sides of the glass, where the bit will go in and come out, will minimize the likelihood of chipping.

HTH
MAP

 

[ScottM]

matt,
i can help you.
i've done them free hand with a power drill, spray bottle and some duct tape.
when i did karls 180g it was ~ 8 min for the 1" bulkhead and ~15 for the 1 1/2 bulkhead.
your 90 will be quicker
pick a day next week and i can meet up and show you how to do it.

 

[Matt L.]

Thank You So Much

Scott,

Thank you so much for the offer! I really appreciate it

I was going to practice on a ceramic tile today from Home Depot (should be approximately the same hardness), and see if I could manage to drill a hole with just my power drill, but if you could come out and at least help do one, I would be so so much more appreciative. In short, any night this week is fine, and in fact, most any time tomorrow is okay too*. Thank you again,

Matt

* I can meet any time tomorrow (Memorial Day) after 3PM. I can meet any time on Tuesday, Wednesday would have to be before 5:30PM, Thursday not until the night (like after 9:30), and any time on Friday.

 

[Matt L.]

Oh, and of course I can thank you for your efforts with beer, money, beer money, etc.

Matt

 

[ScottM]

hows tues afternoon, you pick the time. oh and don't drill tile. no sense in extra wear on the bit.

 

[Piscevore]

Scott, I was talking to Matt about this once and I'm pretty sure I know the answer already, but I'll try once more ...

Ever drilled tempered?

 

[ScottM]

Scott, I was talking to Matt about this once and I'm pretty sure I know the answer already, but I'll try once more ...

Ever drilled tempered?

nope.
can't. or at least i haven't tried it because it WILL shatter.
you can tell if its tempered with a pair of polarized lenses on either side of the glass + some light.

if the whole tank is tempered.... get a new tank, if only the bottom, then drill the back. you can still use internal overflow boxes and drill thru the back.

 

[Piscevore]

Just bought a pair of polarized shades yesterday As far as the tank, only bottom is of "bad" temperment *grins*.... I will plumb the overflow out the back....reading a good book on it right now.

 

[ScottM]

you'll need one lens on one side of the glass and another lens on the other side. hope you bought 2 pairs
check out calfo book, coral prop techniques.
i like the idea of an internal overflow box that doesn't go to the bottom.
you still get surface skimming and you keep your sandbed real estate.

although the shelf idea seems to block alot of light......
somewhere in between?

 

[Piscevore]

That's the one I gots !!

 

[Matt L.]

Tuesday Afternoon

hows tues afternoon, you pick the time. oh and don't drill tile. no sense in extra wear on the bit.

Greg,

Are you still on for Tuesday afternoon? If the weather holds, how about 6:30PM. The tank is currently in my garage. We can move it right outside so we can affix the hose with duct tape. I also have some modeling clay to make a dam.

Matt

 

[ScottM]

john,
6:30 it is.. email me an address and i will see you then.
we can leave it in the garage.
no hose or clay required.

 

[Matt L.]

Where did I come up with 'Greg'???

john,
6:30 it is.. email me an address and i will see you then.
we can leave it in the garage.
no hose or clay required.

I think I was responding to a Greg Hiller post at the same time... I wonder if I called him scott???

Oh well, my apologies, Scott. I will PM you my address, and will make sure I have a spray bottle on hand. In the mean time, do you want to use my power drill? Or will you bring your own. I have both bits, though.

Matt

 

[ScottM]

i have a spray bottle and a drill.

 

[Matt L.]

Thanks to Scott

Four down, and one to go. I will try the last on my own. Thank you so much Scott, and I will post pictures as soon as possible,

Matt

 

[JustDavidP]

Scott.... that's an impressive thing. It's cool to see BRS members come to the aid of others...like some salty brothers!

< D >

 

[Matt L.]

I don't think I would have been able to do it safely without Scott showing me how,

Matt