I've done a lot of reading around here but here's a few things I couldn't find-
Is PVC safe if it is only used for the chamber? The bowl would be a socket or something.
I got some brass plumbing today, should I take it apart and plug the ends to hide the smell (when not in use) or will that go away after a few minutes?
Is 1/8" parts too small? I haven't had a chance to test it yet...
Is there an advantage to an actual mouth piece or is the opening in the brass pipe good enough?

Yeah so I got some lame "noob" questions... Any advice appreciated

PVC is NOT safe.
Just put it in a baggie, it won't (read: shouldn't) smell bad in a baggie.
1/8ths might be a little small. I have a 3/8ths and it is a little too big so IDK.
No advantage that I am aware of.

Don't be afraid to ask man, this is a safe place

Hey, we were all in your position at one time.
Your idea seems like it would work to keep the smell in, and if not, you can one of those glass mason jars. If you don't have one just lying around, go into your pantry and look around, you're likely to find some type of jar that would work. Rinse it out and give it a shot.
You don't want to use PVC, plastic vapors are HORRIBLE for you. I don't think 1/8 inch is too small, it should work fine. Try just sucking through it without smoke, if it seems like its too small, then get a bigger size. This isn't an exact science, experiment! .
And finally, the opening in the brass pipe is fine, the only thing that may happen is that it may get hot, but thats the risk you take with metal parts. I smoked out of a metal piece that had about a one inch plastic(A clear plastic tubing) around the mouthpiece. It was snug, but I'm not sure how that was done. If the hot metal gets to be a problem, you might want to look into that.

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