Yes please be sure to thoroughly clean whatever you spray flammable fluids onto. People on fire is not cool. Neither is having to call poison control.There's no place like this community. It made me smile reading through all the suggestions. Friends helping friends, that's what it's all about.
Not sure about the WD40, you would have to make sure you cleaned everything afterwards. WD40 is also flammable. I would want to hear from @OF. You could give him a PM.
.................................................I'm done with it for today. I still need to get the two adapters un-stuck, but will continue to work on that tomorrow. Thanks for all the help guys.
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So in an effort for all to learn, what method did you try that didn't turn out so well?
And which piece cracked---bubbler (hopefully not) or adapter #1 directly in the bubbler, or adapter #2 (at the top of the glass chain?
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You have been given the answer to your problem at least four different times now, by at least three different people, yet you have not reported trying the prospective solution, nor have you reported solving your problem. Every other prospective solution failed horribly.
You don't have a thermodynamics problem; you have a mechanical problem. I have the same issue multiple times every day, except I don't have a problem. Entirely because I keep a piece of rubber handy.