How can I fix a tap that still drips after I have replaced washer?

I have twice replaced the washer in the bathroom cold tap and initially it's fine. Then after a week or so, it starts to drip again, not only drip but a contant trickle. There seems to be a certain point where it doesn't drip, but if you turn the tap off all the way it drips and you have to go back the other way a little to get it to stop or at least slow the dripping. I used some supposedly super new style washer with a reservoir shaped bit of rubber, I don't really understand what's meant to be so much better about them. I've put 2 new ones on and have the same problem?
Sue Hastwell, September 2004


done
I have just had the same problem with my outdoor tap - replaced valve and reseated but it was just as bad. In the end we had to replace tap.

Jane, January 2005
get yourself a tap reseating tool,you can buy cheap ones.then reseat tap by grinding out the damage in the seat

nick s, October 2004
Have you checked to ensure that the seating for the washer is free of limescale, both on the spigot and inside the tap? Sounds like something is warping the washer when you fully tighten the tap down.

Mike, September 2004