requirements, the scale of the drawings, and the scope and size of the final structure. Trace and vellum may be purchased on rolls that require sizing the paper properly. Trace may be sized by measuring the length needed and using a straight edge, T-square, or parallel rule to rip the paper off of the roll. Trace rips easily and slightly rough edges are expected. Vellum from a roll should be measured to its proper length and then using a straight edge and an X-acto knife on a proper cutting surface trim the paper to its proper length. Scissors should never be used in cutting trace or vellum.