3 ms·

can you explain what "cavity IDs on the DIP molds" means?

• exmadscientist 3y ago
  Things that are mass-produced in very high volumes by injection molding are never molded just one at a time: the molds have multiple cavities to make many parts at a time in a single molding shot. Very often, each cavity will have a marking to identify it: sometimes just a number, sometimes alphanumeric, sometimes dots. So you can tell that if everything coming out of cavity B12 is having quality problems, you probably need to inspect that cavity. Now take a look at the picture in the article of the undersides of the DIP-40 parts. There are two circles, which are either ejector pin locations or just things that look like them. (Ejector pins are the things that kick finished parts out of the mold once they're done.) Inside a few of those circles you find those cavity markings. I'm not sure exactly why the ejector pins and cavity markings (appear to?) coincide, but it's pretty common out there in the wild. You'd need someone who's more of a mold specialist and less of an EE to answer that one.
  • jacquesm 3y ago
    I've looked at Lego bricks more than I care for and I've noticed similar mismatches over the many years that a particular brick was produced, but they were all still original Lego. It could simply be that at some point a completely new mold was made and it has its markings in a different spot. There are also so called modular molds with interchangeable inserts.
    • exmadscientist 3y ago
      Yes, mismatches over the years are completely normal... but not with the same date code and site code.