CAD sheet metal parts drawing drawing specifications, bending line needs to be how to say

The bending line is expressed as a dotted line, which is the same as the center line ...... In fact, it can also be said that the bending line is the center of the bending angle...the picture is not the right representation...the owner needs to pay attention to: the bending line is a virtual line, which is drawn only for the convenience of bending, this will be different according to different bending angles. This according to different bending angle in the direction of positioning will be different, generally are for reference only ...... There is also the unfolding of the map can not be used as a machining of the fixed Xing map, he is only a reference to the material map. Some complex graphics by the three-dimensional direct unfolding after laser cutting material, but rarely out of the formal drawings of the material drawing ...... issued by the official drawings should be the final shape of the part ...... hope to help you