turning my hand into a bluff: does this ever work?

[Jinx]

8 handed 10/20 game. Folded to me OTB, I raise Q[img]/images/graemlins/spade.gif[/img]K[img]/images/graemlins/club.gif[/img] OTB. SB calls, BB calls. SB is a fish, BB is a tightish player who I don't think bluffs very much. BB should view me as the same way, we don't tangle much and I don't think I've ever tried to bluff him. I've been very quiet this session.

Flop comes 7[img]/images/graemlins/heart.gif[/img] 7[img]/images/graemlins/club.gif[/img] 4[img]/images/graemlins/heart.gif[/img]. Checked around.

Turn is a Q[img]/images/graemlins/club.gif[/img]. Sb checks, BB bets 210 into a 210 pot, I call SB folds.

River is 2[img]/images/graemlins/heart.gif[/img]. BB thinks a bit then bets 500 into a 630 pot, I think then realize my hand probably isn't good, so I push for 1500 more. Meh? I'm not repping much but given my image I don't see how he can call with a 7 or even a flush. FWIW I sometimes play QQ or 77 this way, probably not 44 or a fd this way though, but not sure if he knows that.