钢琴在用过一段时间之后,琴槌的击弦部位会出现严重的弦痕,甚至平头,致使击弦面积增大,影响钢琴的良好音质。遇到此种情况,可用打磨的办法使其复原。方法是:先用利刀以击弦点为基准,按原弧度将槌毡削掉一层;然后用砂纸板(将砂纸折裹在长条木板上)从上下两面分别向击弦点处打磨。打磨时,切不可过多打磨触弦处或磨偏。打磨后,要用专用的弯形烙铁或电熨斗将其烫平,但注意不可将槌毡烫焦,变黄。槌毡如果太硬,发音单薄、刺耳,可用排针(将3--4根缝衣服针并排固定在金属 After the piano has been used for a period of time, there will be serious string marks on the striking parts of the hammer, or even flat head, resulting in an increase in the area of ​​the striking strings, affecting the good sound quality of the piano. In such cases, it can be polished to make it recover. Method is: first with a knife to strike point as a benchmark, according to the original arc will hammer off a layer of felt; and then use sandpaper (the sandpaper wrapped in strips of wood) from the upper and lower sides of the hammer point were polished . When grinding, must not be too polish grinding string or grinding bias. After sanding, use a special bent iron or iron ironing it, but be careful not to burnt the felt, yellowing. If the hammer felt too hard, pronounced, harsh, available pin (3 - 4 stitches needles fixed side by side in the metal