Glass Container Thickness

[EmpressC]

Does anyone know what the minimum thickness (in inches) should be for a glass container? I wouldn't want to use something that might crack from the candle heat. TIA.

[EmpressC]

Anyone??? :embarasse

[kandlekrazy]

I don't know if there is a "standard" thickness. If you look at votive glass, it's usually thinner than that used in container candles. The mason jars are thinner than the tumblers I use, but they work just fine. That being said, I personally would never buy anything less than a restaurant quality glass because it is thicker than regular drinking tumblers. I think if you stick to suppliers for candles, you'll be just fine. If you're trying to save some $ and don't want to use canning jars, try IKEA if you have one near you, or a restaurant supplier and you can find some heavy duty tumblers there. HTH

[EmpressC]

Thanx for the reply. Actually, I wanted to make candles using some unique glass containers. The glass is 1/8" thick and I just wasn't sure if that'd be ok to withstand the heat. But you make a very good point with votive containers. I also looked at my jelly jars and they seem to be about 1/8" thick too, and they are ok. So I think I'll be good to go. As always, I'll test test test!

[Bella Luna]

I think it's not only the thickness of glass, but also the quality. Kinda like Pyrex is a lot more heavy duty than some other types of glass.

Also, whether it's pressed or blown would make a difference in the strength/durability/heat tolerance.

[melissa1955]

I beleive I read on this board that if the container can withstand boiling water than it should be safe for candles...

HTH

Melissa

[Stella1952]

Some glass containers will withstand boiling water - a couple of times - before they fracture from the heat stress. The quality of the glass must be considered. Sometimes, thick, cheap glass will fracture before thin, quality glass. Beware of glass from China! HTH

[kandlekrazy]

Some glass containers will withstand boiling water - a couple of times - before they fracture from the heat stress. The quality of the glass must be considered. Sometimes, thick, cheap glass will fracture before thin, quality glass. Beware of glass from China! HTH

Gee Stella, you're bursting my bubble here! All of the glass carried at Gen Wax is from China! On the other hand, I've been using it over and over for testers for about 2 years now and haven't had a problem. I particularly like the square tumblers there and they are very thick and heavy, but I haven't really had any problems with their round tumblers or status jars either.

[EmpressC]

So what do you guys think about stained glass? Would it withstand the heat of a candle? It's 1/8 inch thick.

[Stella1952]

I make stained glass candle shelters but I have never poured wax directly into anything made from stained glass and never will. Stained glass is either handblown and rolled, or machine rolled to have imperfections in it that are lovely to behold. A stressometer will reveal weaknesses and stresses within a sheet of glass. People who do warm and hot glass work have to pay close attention to internal stress to be sure that after annealing, the glass doesn't still have stress that will cause it to fracture.

If you use stained glass, it should be adhered to more stable glass, as in the case of mosaics, or should be so far from the source of heat that it won't be affected. I always contain the wax in a heat-resistant container and set it inside the stained glass shelter. Mosaics are honestly the hot setup because the pieces are much smaller, and therefore less likely to fracture from heat stress.

I'm sure many folks DO pour candles directly into stained glass objects and report never having a problem. Great for them, but I wouldn't want the liability because I have worked glass for 30 years and seen it fail under circumstances I never believed possible! Use tealights or votive glasses to contain your candles inside of stained glass.

[EmpressC]

Thanx for the info, Stella.