3 ms·

If you’re engineering to protect against fraud then maybe you would make them different sizes? Or only make one kind of part?

zaarn 8y ago
That would be my first instinct as well. Atleast when I interned metallworking, the supervisor did have atleast one lesson where they talked about making sure components don't fit into places they shouldn't. If two gears on a machine have different requirements then they should be made to not fit into eachother's places. It makes maintenance easier since there is only 1 correct way to build the machine from any set of spare parts.
- Jabbles 8y ago
  Sometimes that is not enough: In this rocket malfunction, a part was installed upside down. It had arrows indicating the direction and only fit in its place in one orientation. Still, on finding that it didn't immediately fit a technician forced it in: http://www.russianspaceweb.com/proton_glonass49.html#culprit http://www.russianspaceweb.com/proton_glonass49.html#culprit By July 13, investigators simulated the improper installation of the DUS angular velocity sensors on the actual hardware. As it turned out, it would be very difficult to do but not impossible. To achieve that personnel would need to use procedures and instruments not certified either by the design documentation or the installation instructions. As a result, the plate holding the sensors sustained damage. Yet, when the hardware recovered from the accident was delivered to GKNPTs Khrunichev, it was discovered that the nature of the damage to the plate had almost exactly matched the simulated version.
  - zaarn 8y ago
    You can't do much against an engineer willing to weld and cut their way through the parts. Similarly, we can't do anything about people using a soldering iron to make customizations to their motherboards. Everything that happens, it's on them.

3 ms·

If you’re engineering to protect against fraud then maybe you would make them different sizes? Or only make one kind of part?

by viburnum 8y ago

zaarn 8y ago
That would be my first instinct as well. Atleast when I interned metallworking, the supervisor did have atleast one lesson where they talked about making sure components don't fit into places they shouldn't. If two gears on a machine have different requirements then they should be made to not fit into eachother's places. It makes maintenance easier since there is only 1 correct way to build the machine from any set of spare parts.
- Jabbles 8y ago
  Sometimes that is not enough: In this rocket malfunction, a part was installed upside down. It had arrows indicating the direction and only fit in its place in one orientation. Still, on finding that it didn't immediately fit a technician forced it in: http://www.russianspaceweb.com/proton_glonass49.html#culprit http://www.russianspaceweb.com/proton_glonass49.html#culprit By July 13, investigators simulated the improper installation of the DUS angular velocity sensors on the actual hardware. As it turned out, it would be very difficult to do but not impossible. To achieve that personnel would need to use procedures and instruments not certified either by the design documentation or the installation instructions. As a result, the plate holding the sensors sustained damage. Yet, when the hardware recovered from the accident was delivered to GKNPTs Khrunichev, it was discovered that the nature of the damage to the plate had almost exactly matched the simulated version.
  - zaarn 8y ago
    You can't do much against an engineer willing to weld and cut their way through the parts. Similarly, we can't do anything about people using a soldering iron to make customizations to their motherboards. Everything that happens, it's on them.