Shock threshold of glass

[EaglesLegacy]

Hi all, I'm not sure I'm posting in the right area, but it kinda seems like a safety issue to me. I haven't lampworked since November because I lampwork outdoors (until I can afford to safely ventilate my garage). How warm should I allow the weather to get before attempting to lampwork again? It's supposed to reach the 50s sometime this week. What is the shock threshold of glass?

[NMLinda]

Cindy - Glass is most prone to shock when heated too quickly through and past the strain point (~600 degrees). It's not an absolute temperature effect so much as a rate of temperature change. Depending on formulation or how well the starting rods were annealed, some glass is more sensitive to the fast rates of change experienced when introduced into a flame (ie 'shockier') than others. The only thing I've found when working during cold weather, as you're asking, is that I have to be slightly more patient (maybe 15 seconds more) when introducing a rod into the flame than when it's summer. Occaisionally, I find have to also pre-warm certain colors during the winter that I may not have to when it's summer. If you're annealing your beads as you go, then the air temperature won't matter to your finished product, either.

I think it's really more a matter of your personal comfort and how well you can shield you and your setup from the elements since you're working outdoors.

Linda

[RSimmons]

When you consider the temperatures involved with working molten or semi-molten glass, a few degrees here and there in the ambient temps won't make much difference. Linda's right, it's more your own personal comfort than anything else.

Robert

[EaglesLegacy]

Awesome! Thank you guys so much. I've missed lampworking incredibly over the cold months (but not enough to compromise my health) and I'm so eager to get back to it.