Yea, the nano was off, never turned on. I just received it today, still sitting in the shipping box. The glass isn't a ground glass joint, so its not like they slide together. The stem fits but it doesn't slip off or on with zero force, I just assumed this was to make a good seal and that these items had been tested to fit before they were sold and shipped. I guess I'm just reiterating what you said, don't put any force on these glass parts, they are weak. I've had a lot of different glass pieces in my life, none of them have shattered so easily as this did. It's not like I was trying to hammer it into place.
Sorry about that... probably should have been clearer. The glass should slide on very easily, especially if nano is cold. Never measured (or even compared) but would guess the heating element port expands some when it is hot, so if nano is cold it should slide on even easier. All of my glass slides on very easily and most is even loose enough to tilt about a degree or 2 in any direction when on.
As I alluded to above, and has been brought up at least a few times in this thread, the glass is made by 3rd party vendors and varies from producer to producer. I know Epic has been trying to find a good solid reliable manufacturer to do them right, but am guessing this still hasn't happened. I think they were test fitting every piece, but with haste to get the MassDrop and what seems from here a bunch of other orders out, this apparently didn't happen with yours.
I've got more than half a dozen GonG adapters and 3 or 4 stems rotating in use and have never had this problem, nor have I broken or cracked even one. Some of mine are over 2 years old now, some are only a couple months old. And, have procured them for others I have turned on to the nano and no problems with theirs either. Hopefully your replacements will be of the same quality. And not sure of the extent of your experiences with glass, but I can tell just from the pic you posted that I have weaker/thinner glass that I use regularly that doesn't usually break either (best example M > M connectors that come with cheap Chinese bubblers).
If you want to use your nano while waiting for replacements, just put them end to end and hold or use the silicone as I mentioned above. Can't recall offhand who else had this problem recently, but may want to look at posts from
@The Stranger from about a month ago. He had this problem and IIRC, there was some discussion about it then.
Also if you haven't yet, get in touch with Epicvape about it. They've been very good in the past about getting replacements out quickly. Not something you or anyone else should have to deal with, but it is what it is.
Whatever you do, don't try to force glass on to metal! I guess stronger glass could squeeze the metal instead (tho don't think any of my glass would), but the glass is more prone to break than the metal is to be squeezed. And, any nano glass I've seen slides on VERY easily, most with plenty of room to spare. Hope some others may learn from this in case their glass also isn't right.
