Well I voted 2 disks, even though I've only made one that I consider successful. (and it was really hard to send it off to You Pick 9, but I did it)
I'm hoping that I will be able to make more now that I did one that was actually hollow and didn't just have a bubble inside, LOL.
I need to go do a search for using the puffy mandrels I guess, because I just assumed you built the discs but blew them out a little thinner than just heating the glass until it expanded as far as it would go.
And I see I was more or less right!
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I'd love to hear some actual user feedback on the difference in the beads.