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The Molding Cycle, continued


Now, let's make it a bit more complex. The addition of the draw at the bottom of the mold makes things considerably more complicated. There are several different names for the blue parts in the above animation. I'm used to them being referred to as "sliders", so that is how they will be referenced here.

These sliders are most likely the pieces that have been lost from JoHan's tooling, which has been the subject of great debate among many modelers lately.

The animation is not 100% accurate, but I wanted to keep the pictures somewhat simplified - for my own sake.

1. The mold closes, with the guide pins aligning the sliders and pulling them tight to the "protrusion" (for lack of a better term) and builds pressure to keep it closed.
2. The plastic is injected into the mold under high pressure (up to 1000psi) to form the part to the cavity.
3. The mold stays closed while the injection unit refills, also allowing time for the part to cure.
4. As the mold opens, the sliders move away from the "protrusion" on the stationary half of the mold. They are spring loaded to move to this position, with the guide pins to pull them in tight to form the shapes needed. The mold opens fully, with the part staying on one half of the mold. The protrusion on the stationary side is set up as a group of wedges, allowing it to collapse upon extension of the ejectors.
5. When the mold opens, the ejector pins come forward to push the part off of the mold face.
6. The ejector pins retract, and it all starts again.

This is a very simplified explanation of the process, but there are more complex mold manuevers yet to come. The new pages and animations will come as time allows. I'm not a great artist, so the page updates, with the animations, take a couple of hours to put together.


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