在清绘地形图的作业中，用小笔尖描绘小符号和短直线，都要求笔尖下墨流畅、绘出的线条光滑实在、两端方正平齐、粗细均匀一致，普通笔尖较难达到这些要求。我在工作中试将普通小笔尖修磨成“小方头笔型”（如图1，其数字单位为毫米），克服了这个困难。目前，我们单位多数同志已经使用。现将修磨方法介绍如下： In clear topographic map operations, with a small tip to draw small symbols and short straight lines, require the pen to ink smoothly, draw the line is smooth, both sides are flush, uniform thickness, common nib more difficult to meet these requirements . At work, I tried to trivialize ordinary small nibs into “little square pen type” (Figure 1, the unit of number is millimeters). At present, most comrades in our unit have already used it. Grinding method now introduced as follows: