>Now admittedly the guy does put the responsibility on the operator, but it appears CAD packages can indeed calculate this for you. So long as the right info was input into the program, the formula should be programmed correctly and the operator should be able to have confidence in the results!
"Should" is the operative term. I can tell you with that having hand checked the automated results of several CAD packages at developing sheet metal flat patterns and finding unexplained variability and errors too many times to count that if you want confidence in the dimensional accuracy of a sheet metal part, you need to develop it by hand. Especially for anything over 5mm in sheet thickness. As far as I'm concerned you really can't engage in sheet metal design without being able to manually verify the development results, so in a sense it is up to the designer regardless of the capabilities of the CAD software.
To be fair, I'm picking on one of the hardest physical manufacturing processes to actually get right - even CNC brake presses have a great amount of variance in calibration (e.g. the amount of bend allowance you need to make for various sheet thicknesses...) across different suppliers, materials, etc to produce physically identical parts. The valuable lesson for a fresh designer is don't trust your 3d representation of the part, don't trust the manufacturer specs on ANYTHING and always prototype. I'm guessing this is why people tolerate it - the world with 3d CAD is still a vastly nicer place to be an engineer than otherwise, so we just rationalise away the shitty parts as a reasonable price to pay.
I'm guessing this is why people tolerate it - the world with 3d CAD is still a vastly nicer place to be an engineer than otherwise, so we just rationalise away the shitty parts as a reasonable price to pay.
Yeah, I know. In my experience, engineers are normally immensely pragmatic people. My dad was an engineer, so I have a lot of respect for the profession. It would just be nice if CAD would be more open.
"Should" is the operative term. I can tell you with that having hand checked the automated results of several CAD packages at developing sheet metal flat patterns and finding unexplained variability and errors too many times to count that if you want confidence in the dimensional accuracy of a sheet metal part, you need to develop it by hand. Especially for anything over 5mm in sheet thickness. As far as I'm concerned you really can't engage in sheet metal design without being able to manually verify the development results, so in a sense it is up to the designer regardless of the capabilities of the CAD software.
To be fair, I'm picking on one of the hardest physical manufacturing processes to actually get right - even CNC brake presses have a great amount of variance in calibration (e.g. the amount of bend allowance you need to make for various sheet thicknesses...) across different suppliers, materials, etc to produce physically identical parts. The valuable lesson for a fresh designer is don't trust your 3d representation of the part, don't trust the manufacturer specs on ANYTHING and always prototype. I'm guessing this is why people tolerate it - the world with 3d CAD is still a vastly nicer place to be an engineer than otherwise, so we just rationalise away the shitty parts as a reasonable price to pay.