I just thought of something. I wonder if CGBEADS can make a graphite mold for the bases with the ribs in them. That would be ideal.
I did have to grind them... and in the pix, there are several that won't work because they need more grinding off the bottom. These are still not a good solution tho... they work with a bunch of o-rings yes, but I want them to fit like a plastic one, and be as easy to pop on and off as the plastic ones. Here, the o-rings can slide off the glass because it's glass, so am still needing a better way to handle the groove for the o-ring.