which bit?

[reefnut]

what kind of cutter should i use with my dremel?i tried a silicone carbide bit and got halfway through then i cracked the glass.after a little more research i found the diamond wheel points.they come in all shapes.which ones is best for cutting glass?

[Rikko]

I've been using just a #7134 for all my cuts and it's held up like a champ. Just do a lazy circle when you make the first hole (like drawing a very bold period) and you're golden.
Just make absolutely sure that you keep the cutting area soaking wet. Some guys have had luck just spraying with a misting bottle, but I prefer hauling it outside and keeping the hose gently soaking the workspace.

[reefnut]

a bold period?do you mean i should star from the center and grind/cut my way out till i gett the diameter i need?

[Rikko]

Yeah, basically. The idea is simply that you're grinding this glass and not drilling it. You can't cut glass the way a drill bit cuts into wood. You're basically chipping away a bit at a time. The only reason for this is so when you finally plunge through the thickness of the glass (call it your pilot hole), you don't accidentally slightly twist the Dremel and break the glass... Picture drilling a pencil-sized hole in a piece of styrofoam and then snugly sticking a pencil in it. Now punch the pencil from the side. Crunch. Once you're in, you just want to grind away in as straight a line as possible.

I know I'm not describing this well... Obviously you're already well underway, but I wonder if any others would be interested in a mini seminar (scary word.. let's call it a demo) some Saturday afternoon at the Pet Gallery?

[reefnut]

whats the thickest glass you have "cut" with a dremel?

[Invigor]

there was a thread on this earlier, about 2 weeks ago...

sears sells these fancy diamond coated bits for $6.99 for a 2pc set. one's a round bit to do the "drill like" pilot hole, and the other to cut away as if you're using a jigsaw..without the jig..

http://www.sears.com/sr/javasr/product.do?BV_UseBVCookie=Yes&vertical=TOOL&pid=00953161000

Craftsman 2 pc. Diamond Point Set
Sears item #00953161000 Mfr. model #5007150-50

[Rikko]

As far as making actual holes in a tank, i"ve only done 3mm glass. For testing and playing around I've done some 2mm and 5mm glass but nothing that I applied in a tank. From the sounds of some of the RC guys, the increase in glass thickness makes the cutting time increase almost logarithmically. I think if I needed a 10mm tank drilled I'd rather carry it out to Jack and Wendel on my back (from North Van to boot) than try Dremeling an overflow hole. :D

[Willow]

why wouldnt you just buy a diamond hole saw if you drilling all these holes?

[Rikko]

Well, partly because I'm an idiot, largely because the only one I was able to locate nearby was $75 (and no glass shops were selling used ones nor terribly polite about being asked). That expense just isn't worth it to me when I did 3 different-sized holes for just one project.