's brother-in-law has been able to leave the hospital after his cancer operation.Then comes the step where experience pays off. The moldmaker has to cut the gates in the mold that allow the sprues to form and the metal to get into the mold cavities, and also vents in the mold that allow the air to escape so the mold fills completely. If not enough rubber is cut out, or if it is done improperly, the castings don't form; if too much, then you have a lot of excess to cut off. Since the rubber is so tough, each mold generally requires a single surgical blade to cut the channels. These are quite sharp, mind you. (Sorry, Al, I really didn't mean to distract you... How's the finger?) Once the channels are cut, alignment notches are also cut out and the mold is marked and labeled. The finished product(s) can be seen in the photo below.
Note the locations of the air channels, pouring channels, and the alignment pieces. The picture below shows the labeling system and exterior alignment notch.
But here's one section of the real mold storage area!
