anyone good at drilling?

[svynx]

If you look at an earlier post by me, I have a 120 gallon tank that I was looking to sell. The only reason I was selling, besides the fact that it takes up a lot of floor space, is becasue I got into salt tanks. And I don't ever want to get into overflow boxes again. Then I got to thinking, I could drill it. So I tried on a few spare 10 gallon tanks I had sitting around. Needless to say, I'm not comfortable drilling such a big tank myself.
Are any of you good at drilling glass, and wouldn't mind drilling mine? All the holes would be in the back, since I think the bottom is tempered. I would make a closed loop on it if I went this direction.

Let me know.
Joel

 

[NCNBilly]

What size? The largest I have is a 1 3/4" for 1" bulkheads. I've drilled plenty.

 

[2turtles]

I've drill a few too. I have a diamond hole saw made for drilling glass for 1 inch bulkheads. If you don't have one you need one first. A couple thoughts: If you have a drill press, use it. However pending the size of the press and tank may limit where the holes go. GO SLOW and use a spray bottle to keep adding water to the bit as it cuts. Oh yea be sure to GO SLOW.

Before you start resolve to yourself that I don't want this tank and if it works - sweet - but if it cracks well you didn't want the tank anyway.

If you were successful at drilling the smaller ones, you will be successful with the bigger one.

See you on Sat Joel

Greg

 

[svynx]

Hey Greg
I drilled one with a hole saw that had a pilot bit and that one worked well. The other one that i drilled didn't have the pilot, and it broke. I guess if worse comes to worse, then I could always replace the back piece with one that is predrilled. I haven't even thought about what size holes I would need. If I went ahead with this project, I would do a calfo overflow with two drains, and two returns. Then there would be 3 holes for the closed loop. two returns and one supply. I wouldn't be looking for a lot of flow, just something to take a powerhead or two out of the tank. So a total of 7 holes. I think that 1" bulkheads would be enough GPH.

 

[2turtles]

You need to go to a shop that deals in making stained glass items or order a diamond hole saw online. When I bought mine it was about $75.00. If you are wanting to drill 7 holes in one piece of glass you need the right stuff. Most I drilled was four in one piece of glass. That was for a custom tank I was building

 

[NCNBilly]

I got mine of ebay - a whole set for around $8 and I've drilled probably 15 holes with it. It doesn't cut as well as it did when new, but its got a few left in it before its dead. Going slow and lubrication are the key. (aint it always)

 

[svynx]

I've got a set from ebay as well, but it doesn't have a pilot bit. I used to work for a flooring company and the first time I drilled glass was with a tile hole saw. You use the pilot bit which puts about a 3/8" hole, then the actual hole saw has a 3/8" dowl guide that goes into the pilot hole. That way it doesn't move around, and it's centered exactly where you want it to be. The next time I did it was with just a diamond saw, and it moves around quite a bit. I guess I was just too excited to keep it still long enough for it to get started.
Joel

 

[2turtles]

<a href=showthread.php?s=&postid=13926930#post13926930 target=_blank>Originally posted</a> by svynx
The next time I did it was with just a diamond saw, and it moves around quite a bit.

This is the reason for the drill press. Bit does not move, it goes in square and use can control the drilling pressure.

 

[svynx]

The only issue I see with using a press would be supporting the tank so it doesn't move around. It's a big tank, and weighs quite a bit. I guess I could just set it on a low table even if the drilling area isn't on the press itself.
I'll start asking around.

 

[Jandree22]

I drilled 4 holes in my 75g with a 18V cordless drill. The trick to stopping the bit from sliding all over the place is starting the cut by putting a slight angle on bit-to-glass. This will start cutting a semi-circle, maybe 1/3'ish. After you've got a little groove started on the one side, you can slowly work your way to flat on the glass with the entire bit and the groove will hold the bit in place.

For lubrication, I drilled my tank over the summer, outside in the lawn with a garden hose and full stream flowing over the cutting area. Obv. that isn't ideal now that it's < 40*F outside, but maybe a garage with drain would work okay for this? You can't use too much lube, and water is the best lube for cooling.

And regarding the time it takes, I agree. It took me 5-10 minutes of full speed to get through each hole. You don't want to apply hardly any pressure, just the weight of the drill is good. It'll slowly grind through. Too much pressure results in excess friction and heat. It's better taking 10 minutes to get through a single hole, than it is taking a half hour drive to TFP to buy a new tank

I also used copious amounts of duct tape on the back side of the hole to assist with dampening vibration and preventing the circle of glass to fall on the opposite pane once I broke through. Not really necessary, but I figured it couldn't hurt.

Ultimately, while initially a little scary, it's not hard at all... just some things to take into consideration and good prep work goes a long way in success. Take your time is the most important. FWIW, I successfully drilled through a 20gal tank on the first try without cracking it, and that glass is MUCH thinner than my 75 (more prone to cracking).

I too used a cheapo 1 3/4" Chinese Ebay diamond bit.