What could I use to blend into glass to block UV light?

What could I use to roll red hot glass into(so it will stick to the glass) that will help it block ultraviolet light(aside from broken/crushed glass that's already UV resistant) and will let the glass stay relatively clear and colorless?

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Steve's got a good point. Regular soda-lime window glass is a good UVB barrier without modification. Float glass specially manufactured for extra UV resistance (Low-e glass) would block most of the UVA, too. Maybe a separate enclosure around your chamber?

The idea of rolling hot glass in UV-resistant frit probably won't get the results you want. It'll most likely either hose the transparency through refraction (best case) or shatter upon cooling from COE issues (less than best case), or probably both (much less than best case).

If you really want to formulate your own UV glass, I'd suggest Cerium Oxide as an additive. That's what is most commonly used in sunglass lenses to increse the uv resistance. You want optical grade, not the cheaper industrial grade. I don't know the usual proportions, so you'll have to experiment. If your glass turns yellowish when it cools, you used too much.
The Ideanator (author)  RavingMadStudios7 years ago
That is something I will have to try. Im going to be using the colorless variety of alcohol bottles as they are usually pretty thick(I think. I'd have to test it out) for the basis of my bulbs.
DISCLAIMER: I am now totally making this up, as I have never tried anything like it.

If you want to coat an existing bottle rather than blowing a new one, I think your most likely approach would be to pound up a few identical (to the one you want to coat) bottles into frit, add the cerium, do a pot melt in a furnace, then dunk a preheated bottle into the melt to coat it. Using identical bottles from the same manufacturer doesn't eliminate the possibility of COE incompatibility, but it does improve your odds a bit.

I don't know if rolling a hot bottle in a pile of Cerium Oxide would work or not. My suspicion is "not", but since I've never tried it....
The Ideanator (author)  RavingMadStudios7 years ago
Would it work if I made cerium infused glass, ground it to powder and rolled the hot glass in it then heated it some so the outer layer just melts so as to have a smooth surface?
See previous disclaimer.... That said:
You'd have to get it really hot but still take care to not let the bottle melt, and probably marver the surface to smooth it out, but you might get past the refraction & COE issues that way. It would be a pretty finesse-y operation, though. In the long run, it might be easier to just blow a new bottle, because by that point you'd be using all the same tools and most of the same techniques anyway.
In theory, that is. I'm a kilnworker and occasional lampworker, so my understanding of real-world glassblowing technique is entrely academic.
Most glass is already somewhat UV blocking. Define "UV blocking" in terms of wavelength.

The Ideanator (author)  steveastrouk7 years ago
Think miniature ionization chamber, a wide variety of gassified substances, like mercury, neon, argon, helium, hydrogen, etc
orksecurity7 years ago
There are UV-blocking films which can be applied after it cools; that may be a better bet than trying to find something which will survive glass-forming temperatures.

lemonie7 years ago
You'd want to melt it in a kiln.
Look out for RavingMad' answering this.