Originally Posted by Carbon
I don't think it's important for the nipple to be able to 'thread' itself into the drum. With the larger diameter pipes you're working with I don't think you'll be able to properly thread the nipple because the drum is curved and more pronounced the larger you go.
If you're using a locknut it doesn't matter. The hole should be just large enough for the nipple to slip through. Just make sure to use an elbow that's threaded on the inside on both ends.
that makes sense.. i didn't think of it that way.. if they say the OD is 1.9.. im guessing a 2" hole saw?... and i planned on having a support on the virticle pipe exension so that should help too..
also.. are people using the 'close' nipple where it is really short and fully threded.. or are like a 3" nipple where the middle has no thread