Note on alignment
to special sockets and bocals
About the grinding: be careful not to grind more than neccessary. The steadier the bocal is in the socket, the better. Grind the whole surface at the same time, but emphasize slightly the pressure at the bottom end. When you can begin to insert the bocal, you know its soon time to stop emphasizing the bottom. Focus more on the upper section. May sound complicated, but it's not.