Documentation/ Drafting of Complex Components Inquiry

Hi all, as a mechanical drafter for the past 3 years, my main subject matter has primarily been sheet metal design. Per the attached image, I've designed, modeled & 3d printed this fan blade, & I am in the process of documenting the design, however my experience has generally involved more rudimentary shapes, & components. Does anyone in this group have any experience with more complex shapes similar to this, that can tell me the best way to go about documenting the more critical aspects of this component. Perhaps provide sources, or samples of their own that explain the bast way to document a complex shape such as this? It would be most appreciated. Thank You.

1 Answer

I would not say it is the right way, but I often get very sparse drawings from customers with a note reading something like "This drawing is produced from a 3D CAD file. Any required dimensions not shown, are to be obtained from the 3D file of the same revision".

In the above case, the 3D file is the documentation. The 2D drawing is mostly just a reference, or a place to show additional details regarding material, tolerances, labeling and marking requirements.

I think you (or the company) need to decide how the drawings will be used in the future. Is it a source of information, or is it THE source of information?

If it is THE source, then it needs to contain enough information to recreate the part using only the drawing. Dimensions, notes, callouts, tolerances, angles, thickness, section views....etc.

That fan blade looks to have a solid core, unless the section happens to pass through two ribs. Solid masses are not a good choice if it is being injection molded. Cutting it via CNC could be OK, but it will make for a greater load on the motor when it tries to start due to the added mass.