在平磨上磨一个工件的两面相平行是件容易的工作。但是,要想获得另外两个侧面与该两个平行面相垂直就不是那么容易了。这里有一个行之有效的加工方法:首先,把工件的两个侧面磨平行,然后把工件竖起来,在一个边上磨出个平底凹平面。该面两边上留出二条窄边。用精密角尺仔细检查,直到将这两个凸窄边磨到与工件的两侧面相垂直为止。然后把工件翻个,磨底面与侧面垂直,最后,再把工件翻个,磨去两窄条,完成顶面磨 It is an easy job to grind a workpiece flat on both sides. However, it is not that easy to get the other two sides perpendicular to the two parallel planes. Here’s an effective method of machining: First, rub two sides of a workpiece parallel to each other, then erect the workpiece and mill a flat, concave surface on one side. There are two narrow sides on both sides of the face. Check carefully with a precision square until these two convex narrow edges are perpendicular to both sides of the workpiece. Then turn over the workpiece, grinding the bottom surface and the vertical side, and finally, turn the workpiece over a mill to two narrow strips to complete the top grinding