A notepad includes a sheet in the notepad having a first line in a first direction, a second line in a second direction, and a third line in a third direction. The first line, the second line and the third line may form an isometric pattern, and the first line is in a first direction. The second line may be in a second direction, and the third line may be in a third direction. The first line may be substantially perpendicular to the second line, and the third line may be substantially perpendicular to a edge of the sheet. The notepad may include a cover having indicia, and the indicia may include special offset solutions, and the indicia may include conversion constants. The indicia may include decimal equivalents to a fraction chart, and the indicia may include piping angles and solutions to the piping angles. The indicia may include pipe circumferences divided into equal parts, and the indicia may include dimensions and formulas for welded fittings.