topic Re: Injection molding animation in 3ds Max Animation and Rigging Forum

Injection molding animation

maarten9K38F — Mon, 04 Sep 2023 08:50:56 GMT

I would like to create an animation of a cross section where a plastic rod is slowly pushed into a (heated) steel element (like a slow version of injection molding). The aim, of course, is for the plastic to take on the shape of the steel element.

I tried to do this myself using MassFX. I marked the plastic as a soft body and the element as rigid. However, when I do this, the plastic tends to behave more like rubber, bulging and buckling in all sorts of directions.

Due to the NDA I can't share any models or images.

What is the right way to animate this?

I’m using 3D Max 2022 for the animation the models are created in Autodesk Inventor.

Re: Injection molding animation

leeminardi — Mon, 04 Sep 2023 13:03:02 GMT

If the shape of the material is straight coming out of the steel plate can you just animate the amount of the extrusion? If it takes some other trajectory you can animate the "amount" variable via a path constraint as I do in this tutorial. A representative before and after image of a non-proprietary example would be helpful in understanding your goal.

Re: Injection molding animation

maarten9K38F — Tue, 05 Sep 2023 05:13:23 GMT

No, it is not a continuous/extrusion process. Like injection moulding, the plastic is forced into the metal element (mould). Once the plastic has taken the shape of the mould, the heating stops, the mould is opened and the plastic is ejected.

Side note
I must say you have wonderful tutorials on your channel, I will definitely use them for other animations.

Re: Injection molding animation

leeminardi — Tue, 05 Sep 2023 12:22:23 GMT

@maarten9K38F thank you for the compliment.

Is the process that you are trying to animate something like the following where the plastic is being transferred from the barrel to the mold?

Re: Injection molding animation

maarten9K38F — Tue, 05 Sep 2023 12:57:33 GMT

Yes, that's very similar to what I'm trying to achieve. But my situation does not have a barrel, it is just a plastic rod that is pushed (by force) into a heated steel mould.

I've created the following illustration to show what i'm trying to accomplish without breaking the NDA.

The ejection of the bar from the mould will not be shown in the animation.

Re: Injection molding animation

leeminardi — Tue, 05 Sep 2023 16:47:00 GMT

You can animate the movement of objects used in Boolean operations as I have done here.

In the attached file I animated the movement of a box that is being subtracted from the shape that fills the mold.