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I'll probably post this in some other "things" comments as well. I'm wondering what you would suggest to seal a fdp 3d printed vessel like this to make sure it holds water a long time. Ill tell you why...

I am working on a bud vase like thing. Of course, it needs to hold water for a long period of time. The problem is, when I put my lips to the top and blow, air comes out somewhere very slowly - slow enough that you can't hear it, but quick enough that my cheeks lose inflation :)