I’m working on an art project and I’d like to try frosting the inside of some bottles. The bottles will potentially get hot so I don’t want to use the spray on stuff. There appears to be a “glass frosting powder” that might do what I want but it sounds like nasty stuff. Does anybody have any ideas? Thanks!
You could use acid to etch the inside. Many etching products designed for working with glass are a paste but I am sure there are more liquid ones available.
I’d have to go with a glass etching solution. It comes as a liquid or a cream, but obviously for your application you’ll want the liquid. Pour it into the bottle. Leave it long enough to get the level of frost you want, pour it back into the storage container and rinse thoroughly.
Note that this stuff is extremely caustic and hazardous and observe all safety and handling precautions.
What about using a sandblaster on just the inside? You won’t have to deal with caustic chemicals, and if you already have an air compressor, you can pick up a cheap blaster and some blasting media at Harbor Freight for 30 or 40 bucks.
I think it’s going to be tricky to sandblast the inside - even if you have a nozzle that will reach inside the bottle, you’re blowing a load of air inside it, which is going to rush out of the neck, tending to eject your sandblasting apparatus from the bottle.
If you manage to constrain everything so that the nozzle stays inside, the escaping air is still going to blow out all the abrasive through the neck - possibly abrading the neck area more than anywhere else.
Yeah good point. Sandblasting might not work in the case of a bottle, unless you just frost the outside rather than the inside.
Cover the outside of the bottle in numerous layers of tape/anything else that would withstand the sands/ can be gotten off with water and elbow grease. Sandblast the inside by holding the nozzle a few inches above the opening and slightly to the side… Problem solved.
What about just dry sand? Put it in the bottle, and put it in a rock tumbler, or a paint can shaker, or something. It might take a while, though, and it might not be as uniform as using the acid.
Thanks for the responses all.
Do I have to do anything special to dispose of it? I’d prefer not using anything that is so hazardous I can’t just throw it out or dump it down the toilet.
I’m sure that would work eventually. I knew someone who used a rock tumbler and raided the neighborhood’s recycling bins to make their own “beach glass” for resale.
Unless the OP already has equipment like a rock tumbler, the liquid glass etching solution sounds like a better bet to me.
What about thinning some white glue with water and swirling it in the bottles. Drain out the excess and let it dry. Should make a nice slightly opaque film on the inside of the bottles. You could even add a little dye to the glue if you wanted a colored inside. Obviously these would just be decorative and you couldn’t put water inside them.
I have used Armour Etch and Bath and tried a thin white paint. All gave unsatisfactory results when compared to a commercially etched or sandblasted look.
The Armour products are need very clean glass and still give an uneven etch in many cases. Paint is also very hard to get an even coat.
Turn it inside-out first! Duh!
Do you guys thing I could create my own sort of tumbler? I was thinking of rigging something up to rotate a bottle on its side for a few days, filled with some sand. Do you think that would work?
A strong aqueous NaOH (Lye) solution will etch glass. It may not be as deep or exactly what you want, but you can buy Lye at Home Depot (or similar). You have to be careful as lye solution will eat your skin, make you go blind, and is very nasty stuff. It gets very hot when you mix it with water. It is nasty stuff, but anything that will eat glass is going to be nasty.
It isn’t as bad as Hydrofluoric Acid (which does a wonderful job, but is really, really nasty). If your bottle isn’t too big, a tablespoon in 12 ounces or so should work in an hour or so and that you can pour down the drain if it is clogged.
Keep in mind that lye is nasty, nasty. It will eat your thumb, blind you, and if you drink it, you die as it will dissolve your esophagus before it gets to your stomach. Gloves, goggles, face shield, a plastic apron, and old clothes. Outside with plenty of ventilation. Even then, it is pretty nasty.
But, it will give a light frosting to the glass.
Did I mention it is Nasty?
rp
I understand that frosted light bulbs are coated internally with a thin layer of white clay (kaolin). It is very temperature stable, can be rinsed in with water, but it is not mechanically strong.
There was a lovely story that the process was invented by a new employee. Instead of sending him off for “striped paint” or a “left handed screwdriver”, they explained to him that what the world wanted was an internally frosted light bulb, and sent him off to design one.