Wow! I think I’m becoming obsessed! Hah hah hah! Here is tonight’s handiwork. I made a low D flute then I made flutes in D, C, and Bb. I still have a little bit of pipe left. I wonder what I’ll make tomorrow… I’m thinking a low G maybe.
Of this batch, I’m sort of partial to the Bb which is pictured on the left and turned upside down.
Your are not obsessed! Pipe is just a whole lot of fun to poke holes in; thats all. 
Where did you get your cork? That’s the only thing that has kept me from cranking out a bunch of PVC flutes.
You could just use a piece off of a dowel rod.
Really? And this seals well enough?
…I guess if it’s a tight fit it would, maybe with some added cork grease… Hm.
You could seal it with cork glue.
Just go to your local craft store. It comes in a little bottle with a squirt tip.
(and yes it will stick to PVC. I’ve tried.)
That sounds too permanent. I’d think you’d want to be able to change the intonation.
Yeah, but it would stay in there 
.
Use a dowel slightly smaller than needed, wrap it in thread, and use cork grease or chap stick on it.
dem whistlers…
…ya gotta explain everything! 
Two sources: You can buy corks at your local craft store. Wine bottles, the kind with the plastic top to pull it out. Cut off the plastic top. You may be able to get a local establishment to save you a few.
Ron
I wish. Michaels fell down on the job this time.
If I do find cork there, it’s in a sheet.
Can you cut cork without having it crumble at the cut edges?
Wine bottles, the kind with the plastic top to pull it out. Cut off the plastic top.
I was making a flute w/ 3/4 in. PVC, and I would have needed a cork
from a jug. Maybe that was my problem…
Yep. I make flutes/whistles on occasion [using the same instructions that S.B. is using…i think) and I have no problems. I buy 1/2"pipe, but the rod is just a little too big for the inside. So after a bit of sanding, its a nice, tight fit.
Rock on! Now I see what Ron meant about the plastic tops (I’m not a wine drinker).
Many people make wine. Corks are easy to find.
I use pieces of dowel rod. The 7/8" is just barely too big to fit in the bore of 3/4" PVC and 5/8" dowel is just barely too big to fit in the bore of 1/2" PVC. I cut off a piece for my respective pipe size and sand around the circumference of it till it’s a snug fit down the bore–just enough that it has to be lightly tapped in with a hammer. It can be adjusted by tapping it from either side with lengths of smaller dowel and a small hammer.