Right
A straight edge or a straight edge is a test equipment , which is used in the "Align" to slight differences in height on flat ( planar ) declare areas to check and measure. In contrast to a spirit level , a straight edge usually has no vials , but only a straight surface on which the workpiece is "aligned".
It is usually used in construction , for example in earthworks , masonry or stone processing . Originally it was only made of wood (hence log ). It is a long, straight bar , now mostly from aluminum - hollow profiles , in smaller versions rarely also made of steel or hard plastic .
The straight line receives symbolic meaning in the Confessions of Augustine .
After fresh screed , plastering mortar or concrete has been put in or applied , a straight edge is also used as a leveling batten to level out any unevenness in the surface.