Est. 1998 — 27 years of woodworking knowledge
A weird accident
Howard
>I had a Pyrex measuring cup with a thin layer of either dried hide glue or shellac in the bottom and decided to let it soak overnight with warm water and detergent in it. About a minute after I put the water in it, it exploded and sent small pieces of glass flying all around, luckily I was wearing safety glasses.
Howard
Re: A weird accident
Denis Chenard, Orleans, Ont.
>I suspect hide glue, it is known to pull glass off, actually it is used with that intent in some glass work, AFAIK.
DC
A similar problem
Steve Antonucci
>I had a Pyrex baking dish explode simply by placing it on a countertop (straight from the oven.) The cold counter caused a thermal shock, and it exploded after a couple of minutes of just sitting there (wasn't immediate).
Ruined my dinner...
Steve
Re: A weird accident
Bill Earl
>Pyrex used to be Corning's brand-name for its borosilicate glass products. Borosilicate glass is very resistant to thermal shock and found wide use in laboratory and kitchen-ware.
However, the Pyrex brand name was sold off by Corning a while back. As I understand it, many products now marketed under the Pyrex brand are made of cheaper, conventional glass.
Re: A weird accident
Chicago Bob
>Pyrex or borosilicate glass that has not been annealed properly after molding or being blown has significant internal stresses. Thermal or mechanical shock will �set it off� seemingly at an unexpected moment. Also older Pyrex glass that has been reheated or microwaved a large number of cycles also has the tendency to shatter unexpectedly due to build up of internal stresses. I don�t think Corning much liked to advertise this fact!
Regards,
Bob
GO Tennessee, Beat Penn State!
Re: A weird accident
Miles
>Could it be the dried material swelling as it absorbs a bit of water, but is still stiff enough to develop significant stress against the constraint of the beaker? Like wetting a wooden wedge to split a rock. If your water was just warm, unless the beaker was pre-cracked it seems very unlikely to be thermal shock.
Miles