Originally Posted by cjgenever
I just don't get how a good seal is being made between the pipe and compression nut
As said above, with Teflon tape and silicon sealant.
The weak link will still be the pipe connection and plumbing nut.
I have made and repaired heat sticks for years, and have found cleaning contact surfaces with rubbing alcohol and sealing with silicon sealant to work pretty darn well, yea nothing lasts forever, but that's why I keep a spare or two ready to go.
Fwiw, I would still coat the electrical connections on the element with silicon sealant as an extra measure. Also, leave the end of the stick open for a few days, as I found out the hard way uncured sealant is a conductor not an insulator.