How to drill a hole in glass

[Spiritus]

I want to make an electroscope, a device looking like this http://en.wikipedia.org/wiki/Electroscope and was thinking eazy way to do it is by drilling a hole in the bottom of a glass (drinking glass)... but I got almost no experience with glass.
It is possibile to do it with normal metal/wood drills? or mabye someone know a nice trick?

I will really need this to test my future project.

[Narsil]

There are several issues with drilling glass. Firstly there is the safety concern that a) the glass could well shatter b) getting glass dust every where, ground glass is nasty stuff and you definitely don't want to inhale it or get it in your eyes.

Ordinary drills definitely won't do it, glass is considerably harder than steel. The only practical way to drill glass is with a water cooled diamond bit. It's possible that you might manage it with a diamond burr in a Dremel. but you will definitely need some way to contain the dust and keep the glass cool enough that it doesn't break from thermal shock.

There's also a risk that just drilling a hole will cause the glass to shatter as glass tends to contain quite a lot of residual stress so even a tiny nick (or hole) can make it shatter.

A possible alternative is to search ebay etc to see of you can find any lab glass which already has the required hole.

[Spiritus]

I got a dremel 300 and I seen they have 2 drill heads for glass, but I thought I cheat my way instead to buy a diamond one just to drill one hole.

[Der Tinkermann]

I have successfully drilled holes in the bottoms of jars(not drinking glasses though)with one of those tile/glass drill bits.

Spoiler: ShowHide

[Lady Ashgrove]

go to your thrift store -- start at the lamp section

maybe you can find a lamp with a glass base that is the right size and shape

look through the vases as well - sometimes you find the glass part of one of those lamps "hiding" as a vase

[Mr. Boltneck]

If you have something like a drill press that can give you a low speed and a steady, controlled feed, you might consider the old lapidary technique of using a copper tube as a bit, fed with a mix of water and a fine abrasive like corundum. I know that some people also do this with a wall of modeling clay built around the spot to help confine the slurry. It's not necessarily fast, but it's simple and fairly versatile.

[Wormster]

I once watched a friend "drill" a hole in a glass bottle by using 2 drills HSS ones from memory (first one about 2.5mm and second about 5mm). He did it by hand, gently tapping the drill bit against the bottle whilst at the same time rotating the bit in his hand, it took a fair while to get the first hole trough and even longer to enlarge it!

useful link:

http://www.wikihow.com/Drill-Holes-Through-Glass

[TVC15]

Has anyone tried using a torch to heat the glass to near melting point and then using a heated 'needle' to drive a hole through the spot where needed? I've not tried this 'technique' and really just wondered if anyone else has.

[Arvis]

Has anyone tried using a torch to heat the glass to near melting point and then using a heated 'needle' to drive a hole through the spot where needed? I've not tried this 'technique' and really just wondered if anyone else has.

That just sounds like a bad idea, especially if as a first attempt by a novice.  Sounds like a trick for the expert glass blowers.
So "no" that leaves me out. 

Arvis

[Spiritus]

Has anyone tried using a torch to heat the glass to near melting point and then using a heated 'needle' to drive a hole through the spot where needed? I've not tried this 'technique' and really just wondered if anyone else has.

I used torches before, but personaly... I'm not going to do that, probably cant control the temperature just by looking at the glass.

If you have something like a drill press that can give you a low speed and a steady, controlled feed, you might consider the old lapidary technique of using a copper tube as a bit, fed with a mix of water and a fine abrasive like corundum. I know that some people also do this with a wall of modeling clay built around the spot to help confine the slurry. It's not necessarily fast, but it's simple and fairly versatile.

I will try that

[Miles (a sailor)Martin]

If you have a drill press avalable to use another tequnique that i have seen used(by my grandfather) is a wood dowel with valve grinding compound on the end
slow speed(450rpm or less) and light pressure. He was cutting holes in the side of a Mason Jar,also worked in plate glass and ceramic.
wear your safety gear(face sheild,gloves,long sleeve shirt buttoned all the way up as said above the glass can break as the change in stress is variable.              good luck

                             Miles

[Angus A Fitziron]

I drilled a hole in the bottom of a whisky bottle for a gentleman's challenge. I used a drill bit purchased for the job - a "glass and ceramic tile" drill bit. Brace the work piece in a strong box to stop it moving and to contain the bits if the glass does let go. Eyeshields of course and gloves, Miles' advice is all good!

I created a well around the hole using bluetack and filled it up with water to cool the bit and to contain the slurry. The amount of slurry being produced is also a good guide as to progress which will be slow if my experience is anything to go by. It is also a good guide as to when you have actually broken through (the water runs out!) I was also very surprised how hot the water got. I used a standard electronic control drill at low speed (few hundred rpm). Be very careful as you get through and do not press as the drill will break through and cause a jagged edge. If you can get to both sides of the surface, drill from one side until you have an actual hole, then attack it from the other side. It should give you a better result. You will also need to think of a way to cool the galss once you have got the hole through as the water contained in a bluetack well won't work! I cannot recomend you use my method, so won't give it...

In any case - be very patient - this is a case where slower really is better.

[thren]

Ive used a dremel and the cone shaped grinding stones before to sucessfully put 12mm holes in alcohol bottles.
Looks like this........http://www.hobbytools.com.au/prod1471.htm

Takes a while though

[H. MacHinery]

I don't have any advice, but I have heard of an incident where a cable TV installer managed to drill a hole through a sliding glass door with a regular drillbit - apparently it took quite a long time, but did not shatter the door.  however, once the cable was run through it, it was discovered....

[Angus A Fitziron]

I don't have any advice, but I have heard of an incident where a cable TV installer managed to drill a hole through a sliding glass door with a regular drillbit - apparently it took quite a long time, but did not shatter the door.  however, once the cable was run through it, it was discovered....

[Jedediah Solomon]

I remember seeing a glass pastry cover that looked quite funky, but can't remember if the handle on top was extended from the glass, or had a brass knob. Try a restaurant supply store.

[celephicus]

The inimical Charles Babbage taught himself this skill in order to have a talking point with mechanics (as skilled tradesmen were called in Victorian times). He described it in his entertaining autobiography "Passages From The Life of a Philosopher". I don't have a copy handy, but I recall that it involved a centre punch held point uppermost in a vice and tapping with a second centre punch from above.

Aha, Igor has informed me that there is a copy on Google Books, the bit I refer to is on page 377-378. Quartermaster, an extra tot of rum for that stout fellow! Actually the entire book is highly entertaining, Babbage is an example to us all.