Modifying glass bottles

bio · Working Bee

Not exactly glass blowing but done by glass blowers nevertheless.

When drilling holes in glass bottles made of soda lime I have had limited sucess by starting a tiny hole with a broken file then enlarging that with a conical grinding stone.
This does work but is very tedious (takes hours) and some break.

What would be the correct stone material and RPM to use? Also would the all metal stones work as I never tried them?

Also to cut a bottle end off without a diamond saw have also suceeded very seldom by the lighted string method on a scored line then plunged into cold water. Also tried heating wire to do this which also doesn't really work well. What usually happens is most of the break is clean but most of the time a small portion is not on the circle.

There must be a way to do this without a lot of fancy equipment or perhaps my technique is faulty?

primathon · modified

diamond drill bits

As for RPM? Probably as high as you can get it... Also, I've heard of people running a stream of water across the drilling surface to cool both the bit and the material, along with providing a bit of lubrication.

Damn I want a set of those...

Guest · Tue Jun 14, 2005 2:47 pm

Bio,

I have worked with soda glass for a few years,

I have even blown a coke bottle into a RBF flask, it's all about heating slowly,

The reason you are having problems drilling the glass is because of heat, that's all.

Just run water over the drill bit, as it is drilling, and you won't have any problems,
No need for sand, Just a nice diamond bit, and go for it,

For a bit of fun, what you can do, is just get a lpg gas torch, and slowly heat up the bottom of the coke bottle, slowly, and when hot, blow, and watch the majic,
You must put it in an annealing oven though, which is just a fancy word for getting the glass back to its softening point, and then slowly bring the heat back to room temp,

If you want to know more, just ask,

syn

bio · Working Bee

Cool, I'll try that with this carborundum cone stone grinding bit which does work dry but takes f......g forever.

Turpentine mixed with camphor is recommended as a lubricant for starting holes with a broken file and I always wondered what is the significance of this instead of say regular cutting oil?

Speaking of modifying bottles yesterday I tried the heating wire in the scored line cutting method and it really works great. Cut the bottom off of 2 big thick wine bottles and also the top off of a thin 1L bottle. Came out almost perfect just needing some sanding.

Now full of confidence I thought now I know why I've been saving that glass pot with the star crack about 1/2 inch from the bottom so I turned a Pyrex glass 2L coffee pot into an evaporating dish. Took a little more heat and made a different sound when cracking but came out just fine.

Sure beats the burning string method which I never could get to work very well.