I fought this.........to the piont of purchasing new brake pads.......I fiddled with the old ones....I cleaned them degreased them and I found no change....untill I talked to a sailing friend that said there was nothing wrong with my wheel brake.....he went on to tell me that its not built to lock down the wheel...
it is used when you have the sails up and trimmed nicely when you almost dont need to steer the boat...the point where the sails are steering the boat......then you tighten the knob and it will hold you for a bit....
but my understanding is it is not going to stop your wheel