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Technical Program Outline
Note NOTE All dimensions, axis and angles are defined from a top view
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Rotate2 - the rotate3d function is used to rotate pipe3 about the y axis, with its own origin as the pivot point, -90 degrees.
AutoCAD Grit Chamber Program
layer2 creates a new layer "grit-elbow" for all the elbows in the program
layer3 freezes the "grit-pipe" layer. When a layer is frozen, you can neither see nor alter the objects set under that layer. You only want to work with one layer at a time to avoid interference with other objects. Some elbows and pipes for example over overlap at times and this sidesteps that problem.