Any advice on how to play against and beat calling stations (players that call constantly on shitty hands and just get lucky)?

This is usually the case when I play amongst friends; they're new to the game and so they do unpredictable things. I had a game last night and ended up coming 5th out of 8. My opponents were constantly calling my raises with shitty hands (7,2 off etc.) and they just kept getting lucky on the flops. Bear in mind that my raises were decent sized raises in the circumstances. I just had a really hard time getting my stack up.

The only thing I can think of is to play exceptionally tight and play agressive when I have the nuts. Every hand that was played, except one ( I bluffed him out of it), went to a showdown. And they were always big hands: full house, four of a kind, etc.

Any ideas/help?

Cheers.