This is strange

[Anna]

My GD called and told me one of my candles exploded.The strange thing is it wasn't burning.It hasn't been burned in three days.She said the house was cold,so she turned the heat up.and the vent was blowing on the jar.could this have cause this.Thanks

[SpaceGirl]

Was it a glass jar? Maybe, could be possible if there was a flaw in the jar. Could have started to crack (miniscule) while burning and then the temperature difference from going to warm/hot from cold.

[Anna]

Yes it was a glass container,I called myself inspecting all my jar.It could have had been dropped after it left me.Thank goodness it wasn't burning.

[HeavenScentU]

Could have been the warmth of the heat that made the candle burst. We have our rock candles outside in the garage today and as soon as my DH brought them in to box them up the glass started to condensate, so we let them warm up. We were afraid the glass was going to break but they didn't.

[Lantern Light Mama]

What kind of glass did you use? We only buy glass from candle suppliers because it can withstand temperature differences. Thin walled glass from dollar stores etc might not be tempered glass and is meant as decorative only.

[Stella1952]

Some glass has extra ingredients in it to help withstand temperature changes, such as Pyrex® borosilicate glass. Interestingly, the Wikipedia reports that:

Recent reports suggest that due to the change in manufacturing,[1] notwithstanding the claims made for Pyrex, the glassware can shatter violently and unexpectedly, even when used in accordance with manufacturers' instructions.[4] Claims have been made of severe personal injury during these events. The tendency to break into large pieces, rather than shatter like tempered glass, can produce large cutting edges capable of causing serious injury. Some reports have suggested that older Pyrex was not as susceptible to these problems as currently produced Pyrex. It is unknown whether this has anything to do with the recent change in ownership and location of manufacture of the Pyrex brand.

Flaws or internal stresses in glass are usually not visible to the naked eye. It is best to realize that glass suitable for candles in general is sensitive to rapid temperature changes and one should avoid such. The thickness of the glass is NOT an indicator of higher resistance to thermal shock; in fact, the reverse is frequently true as thick glass takes longer to change temperature, thus it stress cracks more easily when subjected to sudden temperature extremes.

Purchasing good quality glass (Libbey, Anchor-Hocking, Crisa, Corning, etc.) from a quality glass manufacturer is generally worth the extra bucks. I agree with LMM about buying candle glass from reliable candle suppliers.

[PurpleHippie]

I recently purchase very thick glass from Libbey and Anchor Hocking because I thought this would be safer. So even if it is from a reliable manufacture the thick glass isn't as safe as thinner glass? I am just venting here because it has been a fustrating weekend...I stopped using tin because of reports that the tin was burning too hot and the entire candle turned into one big fire ball. I read that there were problems with thin glass and some suggested that foreign manufactured glass might be a problem. Ok, I switch to a thick glass from Libbey. Now there might be a problem with thick glass? So do we now need to add to the warning lable that the container must remain at the same temperature? There isn't any more room to add to the warning lable, at this point we would have to write a small book of instructions. I can't take it anymore. After doing this for many years I think I need to go back to knitting and forget candles! :tiptoe:

[Stella1952]

So even if it is from a reliable manufacture the thick glass isn't as safe as thinner glass?

Sometimes this is the case. Your glass is manufactured by two excellent glass companies. I think their products are as safe as glass can be made affordably.

I stopped using tin because of reports that the tin was burning too hot and the entire candle turned into one big fire ball.

Some tins HAVE caught on fire. It happens rarely and people discuss things like that to hopefully make sure it happens even MORE rarely.

I read that there were problems with thin glass and some suggested that foreign manufactured glass might be a problem. Ok, I switch to a thick glass from Libbey.

Foreign manufactured glass, particularly from China, has had quality control issues. This is a surprise to anyone?

I can't take it anymore. After doing this for many years I think I need to go back to knitting and forget candles!

C'mon, PH! NOTHING in life is 100% safe. We DISCUSS problems in order to be as well-informed and careful as we possibly can. One has to be able to weigh issues and calculate risk. Candlemaking does involve more risk than does knitting, although there's always a chance of impaling oneself with a knitting needle. :laugh2:

[PurpleHippie]

Stella you are right! I know everything has a risk and I have just had a fustrating weekend after calculating my out of pocket cost. So I think I am just being a grouch and maybe a little stir crazy from standing over a pot of hot wax for the last few days.

Do you guys think we should add this information about temperature changes to the warning label?

I am glad all issues are discussed, it's just that sometimes when I finally feel like I've got all my bases covered some new issue turns up. Always a problem.

Now this old grouch is going to go enjoy a few Apple Martini, turn on some holiday music and start decorating!

[cindym]

Enjoy and forget about candles for a while. Good advise, I think I will too.

[bugtussle]

Purple, I agree with Cindym, relax for a while. I have poured nearly 10,000 tins this year. I did report one catching fire, however, the customer never contacted me so I could examine it. Even though 1 in 10,000 is TOO many, it will happen. The good news is that not one glass tureen (fairly thick glass) imported from Spain (or France, I don't remember,) has exploded or cracked while burning, I have poured about 3,800 so far this year.

The most important warning you can put on candles is "Never leave a burning candle unattended" and "remember a burning candle is fire." I would certainly hope all purchasers would know the above before they even think about purchasing one. Carole

[blazerina]

DH spoke with a gentalman who had previously been employed by the local dairy that still sold milk in glass bottles, that you could then rinse and return to the market for a deposit or discount off your next jug. They had recently switched to plastic and DH was saying how they always have to go and change things and make them go from nice and sturdy to cheap feeling, etc etc. He explained that glass has an inherent nature to develop a memory for each bang and knock it receives. It may not break at the time, but very often will at a later date with little to no abuse just because of all the bumps it has had in the past. Of course, temp change and expanding wax, etc are definite triggers.

I think if you buy NEW glass you are being as safe as you can be. Personally I don't trust anything that has been around the block more times than I know. Nor would I ever put $ store thin glass on a hot plate type warmer. I'd burn a candle in it, but never apply it directly to heat in that way. Now, if you KNOW it's got something in it that makes it candle/heat and temp safe- fine. Put it on the sales tag and I will probably warily trust you, lol. But other wise... it just isn't worth the risk. Not that there are any glass/ candles that come with NO risk, but I consider certain things to be a known risk, lol.

But then again... having an OCD hubby has rubbed off on me and you may just call me paranoid, lol.

[Stella1952]

Do you guys think we should add this information about temperature changes to the warning label?

I don't. I would rather concentrate on good wicking and good quality glass. If you give customers a handout on Candle FAQs & Dos and Don't, then by all means include a blurb about it. If you have a website and have an information page with tips and warnings, then include a blurb there, but there just is not enough room on those little bitty labels that NO ONE READS to add more information. I personally have a problem with stupid product labels, such as "Caution: Product will be hot after heating." While some warning labels DO contain information of which people may be unaware, candles, especially candles in GLASS containers are a no-brainer to me... Fire, glass, heat...:rolleyes2

Please don't add any more to your overhead costs by editing your warning labels! There will always be risks and unfortunately there will always be idiots - the two seem attracted to one another... Just do the best you can and make a peace with the rest.

You DO sound tired! I hope the Appletinis did your nerves some good! If not, I recommend chocolate - dark, dark chocolate.