Carpenter's trick
Fig. 1 shows a carpenter's trick that is applicable when trying to line up elements of a beam. Stretch a piece of fish line or string taut along the side of the elements from the end of one to the end of the other. Place a block of wood approximately ¾% inch square under the string at either end. Take a third block of wood of the same thickness and using it as a gauge, move elements from side to side until the gauge blocks shows the string to be equidistant from elements at all points. Secure the elements in place.
Fig. 1. A methode of lining up beam elements.
Edward P. Foster, jr., K4BZL.