Hi guys, I am new at stringing. When I tried to string a raquect with my Klipper M140 and Yonex BG 66 today (18 lb x 20 lb, according to the coversion chart) , I started following the instructions in their manual. For some reason, the string slipped in the clamp, it was like the clamp was not able to hold the string tightly and the coat of the string got some damage. I heard that Klipper clamps may not be able to work on thin strings, is BG 66 too thin? Or I did something wrong? Do I have to buy new clamps? Any advice would be appreciated.