Originally Posted by INTO10s
That right there may be the source or at least adding to the problem she is having. Does HW know she is using polyester strings. To much for a 10-11 yo to handle and not necessary especially now as she is going through a grip change. Consider this setup to soften things up a bit. Stay with the Black code (technifibre brand), 18G OK or can go with 17G, put them only on the mains. For the cross string consider using Technifibre X-One Phase (multifilament) 16G. String the mains 4-5lbs looser then the cross strings ex 50Lbs mains w/ co-poly, 55lbs cross w/ multifilament. If your daughter is playing at least 10-12 /wk then you will probably restring them every 2-3 weeks which is what you would need to do anyway if you are using only the polyester strings. This is done whether they break or not.
That sounds like a sweet setup I'm gonna give it try after this weekends tournament. I restring her rackets every two weeks.