I haven't had that issue with my first box mod...but I plan to purchase lots more of them. I am glad you gave the heads up that this may happen. I think what I will do for my next one to be safe is put some super hard epoxy around the inner surface of the hole and let it dry, to build it out some (make the hole smaller). Then I'll carefully open the hole back up to work the 510 connector in and lock that down with some more adhesive.
Oh btw, I did have to build up the positive side of the internal battery connector with a small dob of solder, because my protected 14500 battery positive end didn't quite reach. I am SO glad I read that tip before I made the box because when I first tried to fire the thing and got no power...at least I didn't try to trouble shoot the whole circuit. I just opened it up, looked at the positive end of the battery and realized it wasn't quite making it to the positive battery connector! I think Hoog suggested that in a thread somewhere...thank you for that!!
ice