Injection molded toy dinosaur technical info

[Leonardo Aguiar]

Hi guys,

I am new to the injection molding process and want to understand it better.

I'm looking for more technical information related to how the toy dinosaur in the following video is made.
https://www.youtube.com/watch?v=w5KRawOXy4U

I understand what is going on in the preproduction part involving CAD, clay sculpting, silicone molds and then the foundry part. In this case mold for the injection was made at a foundry by casting metal, right?

I have read online about injection molding design guidelines and some of the things I read about state that draft angles and undercuts are key issues to be considered when designing for injection molding. When the part has texture (like the dinosaur) draft angles need to be considered also (stated in the 3DSystems link).
https://www.protolabs.com/services/injection-molding/plastic-injection-molding/design-guidelines/
https://www.stratasysdirect.com/resources/injection-molding/
https://www.3dsystems.com/quickparts/learning-center/injection-molding-basics

The Stratasys link states: "If no draft is acceptable due to design considerations, a side action mold may be required." The mold in the dinosaur video has no side action right?
A side action mold has extra moving parts right? For example, the grey pin assembly that moves up and down at the bottom of the mold in this video classifies it as a side action mold right?: https://www.youtube.com/watch?v=1VZwKAnmpAo

In this toy dinosaur's case are draft angles and undercuts not important because the chosen material for the injection is flexible and it allows for the part to be manually "ejected", right? If the material was rigid the part would stay stuck in the mold right? What flexible material could this be?

Thanks for the help.

Best Regards,

Leo

[MTUHusky]

Hey Leonardo,

Yes, that mold appears to be cast aluminum.

There does not appear to be any side actions (This would be almost impossible to do by casting, would have to machine by cnc after). Yes, a side action would be a moving slide controlled by a horn pin, servo motors or hydraulic pulls.

Correct, the ejection stage is only possible because of the softness of the plastic at the ejection temp. A stiffer material would most likely stick in that mold.

For the material type, my guess would be a thermoplastic elastomer. Something with rubber base but I am in the automotive field and am not really familiar with soft toy materials.


Husky