The complexity of ascertaining that the drawings during the drawing thereof remained in accord with proper and correct dimensional relationships of other portions of the drawing(s) required constant diligence and care, all contributing to increased difficulty in the drafting as well as requiring extended times periods of exacting work per drawing or portion thereof. Some of those problems and difficulties arise from the historical approach to drafting, using pin-pricks and the like on the paper on which drafting drawings are being applied, and making the drawing(s) and thereafter applying to the sheet a scale-data line of varying complexity. While the invention of the above-noted patent utilizes a tripod arrangement of helve-head-mounted three spaced-apart roller surfaces positioned for bearing on an upright flat edge surface extending along an x-axis of a drafting board, the present invention while utilizing the same principal and arrangement also discloses another comparable embodiment, but together with additional problem-solving features directed to entirely different problems and difficulties facing a draftsman with the state of the art prior to the present invention.
This invention, inclusive of the non-wobbling and rollers features utility of the above-noted patent, is directed additionally to a novel T-square and to a combination thereof with a novel drafting board.
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