Part of a die for casting/extruding plastic?
Close enough, its a bottom plug for the blow mold cavity.
This customer wants four molds built (12 cavity), that means we have to build four Parison molds, four blow molds, 72 (plus 4 spares) core rods, and slew of other misc parts. (They want two spare mold sets)
I turn this part to plus .005" over size, and cut the top detail (angle & diameter) to make that little protursion I have to turn a ring on the top of the part, then machine most of it off, I cut the grooves into the body, and then I have to remove all the machining marks from the top (perfectly smooth).
Then it is sent out for heat treat to 46-48 RC, when I get it back, I have to grind the length to +.0005" -.0000"; then grind (on center) the OD to dimension with a tollerance of +.0000"
-.0004" , i have to grind the section just above the top groove .0004" smaller then the body. This .0004" smaller and the grooves are there to allow the air to escape when the air is blown in to form the plastic to the blow mold cavity.
once that is all done I polish (10 different steps) the top (Mold area) to a mirror shine, there is no plating just polished tool steel.
I also make the neck rings for this job, the neck rings are the part of the mold that put the threads on the bottle, (no I don't use a tap to cut the threads :wink
My friend that has the CNC's does the cavity's for me, and I turn the core rods.
Ton of work in this project, it's cool to watch one of these injection blow molds run.
The plastic is injected into the Parison mold around the core rod; the parison is what controls how much plastic is used, and the shape of it and the core rod is critical.
Then the machine opens the mold's the 12 core rods (with the plastic on them) are lifted and moved over to the blow mold, while 12 other core rods are put into the parison mold.
The molds close the plastic is injected to the parison and air is blown in through the core rods in the blow mold to shape the plastic bottle.
The molds open and it rotates again (there are three set of core rods in the machine) the molds are closed (parison injected with plastic) (Air blown into the blow) and the finished bottles are removed from the core rods by the pick tree. Three different stations.
Really cool and it's amazing how quickly this all happens.
