Metal straightedge

Get a long metal straightedge! Wood blanks work as well, but they do not have that well defined edges and they can bend out of shape without you knowing, depends on the humidity of the room. We started out with something similar you see below the long straightedge – no, you don’t want that. Get a long one, this is 1 meter stainless steel. Not that expensive when compared to a disproportional boat.