Cheese
Member
1.1. With injection molding... the cost is in the machines, the supporting energy infrastructure, the building, the molds... not so much the very few guys needed to operate them. Running them more often is just pure profit out of the same cost. If you offer enough money... there are always people willing to work. In fact, if you stop a production run... you got to clean the whole thing out which costs..
2. If you have a mold with multiple chambers you might want to use a chamber number. In case you find faults in the end-product you can way easier deduce if it's random or chamber-specific and act accordingly.
Or it stands for production run number X in that month.
Yeah that makes sense too. They came out later so they probably included known possible improvements into the mold. Removal of the two notches on the side meant adding metal back into the mold, something that isn't very popular... then when the mold wore out, the new one got the improvements too.
2. That's a possibility that this is a multiple cavity tool.
3. Ya, mold makers hate to add metal, they'd rather come up short and then have to machine a little more metal away. If they did insert the tool or weld the tool, there should be some very faint witness lines visible in the area.