nothing over 18lbs even on the best machine in the world. those rackets are never made to take high tension, and they'll bend inwards instead of deforming and bouncing back into shape when unstrung like new generation rackets. btw y dont you keep the racket? i certainly for one would buy it.
do u no any site that tells u the maximum string tension for that racket?...just making sure cuz i dont want ma US$15 racket to crack
If it's only $15, definitely NOT even worth for a string job in New York area. The string + labor will easily cost more than the racket.