For all the stringers that string for themselves or for friends i was just wondering what do you do when you face stringing rackets with grommets that need to be replaced? Some rackets i see have a one peice grommet system, so does that mean if 1 grommet breaks off you have to replace the entire thing? Also, is tubing for only the center main strings? or can you use that to replace grommets? thanks for helping a newb out.