Strain point

This is the temperature at which the molecules in the glass stop flowing and moving. Below this point if the bead has not been annealed correctly these stresses will remain in the glass. (unless the glass is then subsequently annealed).

The strain point varies for each glass depending on the manufacturer, elements contained within the glass and the coefficiency of the glass

Effetre glass

The annealing temp is between 493C - 520C but the strain point is 448C

Bullseye

The annealing temp is 504C and strain point is 437C