| 摘要 |
An attachment for a drafting machine having a protractor head has a scale which is securable to the head. By operation of the head, the scale is movable on the drawing board between a first position and a second position disposed at a predetermined acute angle to the first position. On the ruling edge of the scale, there is an index point which is usable when the scale is in the first position to mark the location for the placement of a required symbol. A template is mounted below the scale for rotation about an axis perpendicular to the drawing board and this template is provided with a plurality of outlines which serve as stencils for applying symbols to a drawing. An indicator on the structure supporting the template enables a particular symbol outline to be selected and placed in a position which will coincide with the marked location when the scale is moved to the second position.
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