Don't know if it is so much of a modelling block, just so many other distractions.

Internet, FB is a big time killer, as well I play a few games.

Sometimes it is easier to fire up NHL '09 (last one they made for the PC) and play a game of PC hockey for 15mins (or more) than it is to drag out the tools and paraphernalia to work on a kit.

As well, I bounce around from kit to kit when I do, work on something that holds my interest for awhile and then the new shiny toy comes through the door and tears my interest away from what I am currently working on.