How to Drill Into a Glass Teacup

Clean and Prepare the Glass Teacup

1). Wash the cup with mild dish-washing soap and let it dry thoroughly. Alternatively, you can put it through a cycle of the dishwasher.
2). Highlight the area you want to drill by making a small mark on the teacup with a fine-point marker pen.
3). Stabilize the cup by putting it into a vise or pressing it into a small amount of modeling clay in the bottom of a shallow tray.

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Appropriate safety wear is essential when drilling glass.gardening gloves image by Sandi Chetwynd from Fotolia.com

Put on your safety gear: goggles, leather gloves and a long-sleeved shirt. Cover your head with a hat or scarf in case the glass shatters and shards go into your hair.
2). Choose the correct size of drill bit to use. You may want to use a smaller bit than the intended finished size of the hole and change to a larger bit after the initial hole is in place.
3). Pick the shank size that fits your tool and screw it onto the drill. Put the diamond bit into your drill.
4). Set up your lubrication method. The bit and the glass become very hot and need to be continuously cooled. You can have someone working with you to pour water onto the heated area, you could set up a hose to deliver a water stream, or create a pool with modeling clay around the area to be drilled and fill it with water. Another option is a spray bottle of water.

1). Start the hole by using a drill press to hold the drill in place. Alternatively, make a hole in a piece of wood or cardboard and place it on the marked drilling area.
2). Start to drill the hole at 2,500 to 5,000 RPM. Lubricate continuously.
3). Drill using light pressure and increase the drill speed slowly. Stop when you reach halfway through the glass.
4). Turn the glass over carefully and drill from the other side if possible. The new hole should meet the first hole. If it's not possible to drill from the opposite side, then continue drilling in the same direction.
5). Reduce the pressure on the drill when you are about to break through the glass.
6). Increase the size of the drill bit and repeat the drilling steps until you have the size hole that you want. Remember to keep the drill and glass cool by lubricating.

1). Remove all stray shards from the glass and hole.
2). Polish the drilled hole using silicon carbide sandpaper if the hole is rough.
3). Clean the glass teacup and the work area before you remove your protective wear.