Bullseye have always been good about publishing info on their glass chemistry and potential reactions, but they have now updated this to include info on rods and stringers, in addition to sheet glass. See
http://www.bullseyeglass.com/images/stories/bullseye/PDF/other_technical/reactive_potential_of_bullseye_glass.pdf?utm_medium=email&utm_source=ExactTarget&utm_campaign=email_20120913_glass_reaction_chart_update&utm_content=email_Download+yours+today!
very useful info !! thanks ;)
I think this is the same one that I posted a little while ago?
http://www.frit-happens.co.uk/forum/index.php?topic=38385.msg615608#msg615608
It's a great chart for Bullseye users!
so it is!