you can buy them at a tobacco ot drug store
The answer is yes. Most pipes need screens to keep you from sucking in the ash. Bongs usually dont use a screen , but you can if you want.
pipe
with a pipe
If you are screwing in -- yes -- If not -- you do not use pipe dope
Pipe nipple is use as connector to both pipe which have female end. It does not same as pipe reducer which nipple has same diameter throughout both end and threaded. Pipe reducer has different diameter for both end and it is use to join different pipe diameter.
Mainly for making water pipe.
You should use black pipe -- Galv. pipe will flake off inside of pipe
pipe dope and teflon tape
You can use copper pipe.
Minimum 3/4" pipe.
Absolutely Not!
A pipe cutter is the best tool to cut PVC pipe.