Can you make marbles using Bullseye & Boro together?
 

My partner has just started using Boro & loves it but I’ve seen some Bullseye for sale - can it be added to Boro or are they totally incompatible??
Please excuse my naive question as I’m a novice at this.

Hi! You absolutely cannot use boro with any other glass besides boro. Same goes for Bullseye. The 104 glasses are compatible sometimes, but not always. Explore the tips and techniques page, as there's a ton of info in there on mixing COEs (or not).

No, absolutely now. The COE's (Cohesions of Expansion) are too far apart. Think of it like jello and ice. They're both solid forms but they don't stick together... and with glass incompatibilities, you could be talking about some glass explosions you don't want to be close to.

Sue

DRAT-I always do that! It
s COEFFICIENT, not cohesions. Why can I never remember that word?!?!?!

The coefficiency of expansion for borosilicate glass is 33 COE, and for Bullseye, 90 COE. That is very far apart in terms of glass compatibility, and as has been stated, likely to shatter dramatically even if you can get them to combine.

Hey Smokaijo, glad to see you found this great glass site! There's so much info here it's glorious.

As my friend Phill says, "Welcome to the Addiction!"

Aye and hide the bank numbers to the grandkids college accounts.

The most addictive glass can get real spendy in a hurry.

There are epoxies that work with glass. You could always make some soft parts and some boro parts and then 'combine' the different glasses by adhering them to each other after cool down. Not quite the same but it's an idea...

You cannot use Bullseye & Boro together, since there COE is too far apart.

I made marbles and mixed soft glass into Boro mistakenly before, and here is the result:

1. The Boro mixture became soft (because soft glass was added).

2. It is full of cracks inside, like cracked ice. But is still a marble shape.