Read and analyze fabrication drawings and other design documentation.
Create 3D models and fabrication drawings using parametric solid modeling CAD software.Create sketches using hand drafting instruments to communicate design intent.Upon successful completion of this course students will be able to: The roles of engineers, designers, and drafters, and how they relate in an engineering environment, will be covered. Students will use 3D parametric Computer-Aided Design (CAD) software to create solid models and fabrication drawings. This course introduces methods of communicating technical information in engineering design. Institutional Research & Grants Development.Direct Transfer Agreements/Major Related Programs.The whole purpose of technical drawings is to disambiguate so you should avoid situations where you could cause issues. The rule probably comes from cautioning that in hand drawing you might have a mistake that causes misinterpretation. The question of extra views is most probably not a problem if you are using a 3D application to generate them. Therefore extra dimensions should be made reference only. This could mean you need to accept parts that at worst are unusable for your purpose. Therefore you dont want to over dimension as this might cause a conflict in your tolerance stackup.
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For example in mechanical engineering typically your dimensioning scheme is interpretted as acceptance criteria. Download as PPT, PDF, TXT or read online from Scribd. Remember that the technical drawing is often interpretted as a contractual obligation. You also dont want to overwhelm the recipient with dimensions. Each projection requires the recipient to think more unless its clear they can skip the image. It can be useful but you also have limited realestate on the sheet, more can be harder to read. Adding a nondimensioned view can be neccesery to clarify some things. But you should take care to minimize confusion. There is no reason why you can not add more views. If in doubt, check with your boss, as it may vary from company to company, or job to job.
So, is there a standard industrial-wide drafting standard/rule? I don't think so. However, for a civil-structural or architectural project that contains numerous drawings, it is sometimes can be considered unfriendly to the users, who have to browse through multiple drawings just to find the information. It seems adequate and better for the drawing of mechanical parts not to provide the redundant dimensions to prevent conflicts, especially when changes require re-dimensioning. My personal view is it depends on the complexity of the work. There are controversies on whether no-redundant dimensioning or dimension-it-all is the better method. But, you need two side views to deliver the complete messages, with or without the top view. So, it can be a complete drawing by itself for documentation purposes. The top view of the sheet metal (with "t" stated) will show all necessary information for fabrication. In my experience, when giving out drawing for plasma/laser/hydro cutting of metal sheets only one view is provided (because through holes are assumed and the thickness is provided in the legend of the drawing). So normally you don't need all three view. Also, in most cases you should be able to provide the hole depths in a well placed section view. Regarding your example with the sheet metal, in one of the two orthonormal view the thickness of the sheet can be seen in one of the views. I can't really comment to whether its in a standard (there are a few), but its generally considered good practice and encouraged. lettering and text, orthographic projections, geometric dimensioning and tolerancing, ASME Y14.5 standard, parametric modeling, drawings and assemblies. Having said that there are exceptions where some redundant dimensions/views might be useful and they are included in the drawing. So, dimensions that can be derived from other dimensions are discouraged. To put it another way: include only the necessary bits to have a complete picture. My understanding is that redundancy and/or views that are not repeated should not be present in the a drawing.