i hawe a few normal drill bits and a propane/mapp gas torch.
5 months ago
Can you not be able to heat glass without the mapp gas
8 years ago
trying to make a bong? i recommend just buying a bit for it, i screwed around for years of broken bottles until i just stopped whining and got myself a glass bit for like $10 but you could probably get one at Harbor Freight for less than that.
10 years ago
try wraping insulation tape arund the area you want to drill. then get a lubricant like butter and smother the drill bit with the butter( a tungsten carbide tipped bit will be needed) and comence drilling through the tape slowly and with light pressure. keep adding lubrication and with some time you will have penertrated the glass.
Buy a glass drill bit. Then you can make bongs for your friends too.
10 years ago
Agreed, then when it breaks it just cracks instead of exploding like the glass bottle my friend put a propane torch to.
Plus torch temperature required depends on the glass type and temper does it not? (i.e. Oxypropane instead of just propane for hard glass)
I would assume so.
I once needed to drill a hole near the bottom of a glass vase and I used a bit. The trick is to go slow (like barely touch the trigger) and to not put a lot of pressure on the bit or else the sharp edges of the bit will get snagged up on the glass and crack it.
Then, you can use a torch quickly to melt the sharp edges.
At least, that's how I'd do it.
A jet torch will easily get a bottle to malleable temperatures, poking it through once it's soft would probably be the best way to make the hole.
slowly let it cool by heating it less and less or it'll shatter while cooling down....
If you can bring the entire bottle to a high temperature before focusing more heat in one spot, it might do the trick. Though you might need to put something through it.
At those temperatures, the whole bottle might lose integrity and collapse under it's own weight.
Otherwise yeah I'd say go for a diamond grinding bit.
You might want to fill it and hold it underwater to reduce vibration and heat, just go slowly.
You could probably get the desired effect with the propane torch, depending on the size of the flame. I've seen a guy turn a beer bottle into a goose sculpture with a tiny little chef's torch and a pair of pliers.
To avoid cracking, you really just need to avoid thermal gradients/shock and vibration. Have you experimented with your torch yet?