Glass and Mirrors - Glass/tile drill bit chips then breaks my bottle

I'm trying to drill a 1/2" hole in a glass bottle as part of an artistic endeavor. ;)

The glass/tile drill bit starts off great until the glass is penetrated through. Then the surrounding hole starts chipping and large pieces of glass breaking. :mad:

Should it put a piece of tape over where I'm drilling ... I'm running out of bottles :o

Any insight is much appreciated,

TIA,

-MC

This might work better. Diamond Drill & Tool (http://www.diamond-drill-bit-and-tool.com/Diamond-Drill/MAIN.htm)
I have used grinding compound and a blunt rod, but that was years ago, long before the diamond age. Now, I have several diamond blades for stone and concrete and they are awesome. So, the link above or other sources of diamond drills look reasonable in price and because they grind their way through there should be less chance for chipping.

GL
Bud

Can you describe the type of bit you are using. Some require lubricant and others coolant. Diamond is the way to go as Bud9051 suggests. If you plan on making many holes it should offset the cost.

It only says Black & Decker Glass & Tile Drill Bit 3/8" fits most major brands

The guy at Home Depot only said to use running water over the spot being drilled.

Maybe I use a three pronged approach:
- Smear vasaline over both the area to be drilled as well as the bit
- Put a piece of tape over the area to be drilled
- Run water over the hole being made as I'm drilling

Sound like a plan or a disaster waiting for a place to happen?

TIA,

-MC

These "spear shaped" bits should be used with a slow speed drill. The low setting of a cordless drill is fine. Start the hole dry until the point begins to dig into the glass. A lubricant such as kerosene or any solvent mixed with some oil should be applied to the bit as you drill. Have someone apply it to the bit with a small brush as you guide the drill bit. Press just hard enough so that the bit is cutting through the glass and stop as soon as the glass is punctured. Now continue with a little less pressure, continue lubricating until the entire bit goes through. You may get some chips around the hole on the under side. Sometimes the problem of drilling the hole is that glass bottles are not the same as flat glass.

would vasaline or engine oil work? just trying to save a trip to the h/w store

Oil will work. I didn't mention in my previous response to keep the bottle from moving and the drill as straight as possible. Good luck.

i found a 1/2" diamond particle drill but, I run water over the glass as I'm cutting and it works MUCH better

thks for all the tips Beer 4U2