# Anim Dynamics Causing Mesh to Disappear **URL:** \ **Category:** Character & Animation\ **Tags:** unreal-engine, question\ **Created:** [November 14, 2026, 9:36pm UTC](https://forums.unrealengine.com/t/anim-dynamics-causing-mesh-to-disappear/2856014 "2026-11-14T21:36:36Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![Dead\_Dogma](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@Dead\_Dogma](https://forums.unrealengine.com/u/Dead_Dogma)\ **Post date:** [November 14, 2026, 9:36pm UTC](https://forums.unrealengine.com/t/anim-dynamics-causing-mesh-to-disappear/2856014/1 "2026-11-14T21:36:37Z")
Hello, I am attempting to create a procedural animation system. Similar to what was done in Overgrowth. In overgrowth the arms / ears have a softness parameter for the bones which allow them to sway with movement. [https://www.youtube.com/watch?v=LNidsMesxSE](https://www.youtube.com/watch?v=LNidsMesxSE) (12:40 - 13:20) I have my character and used an Anim Dynamics node to attempt this. However, this results in the mesh disappearing. I have also watched other tutorials of Anim Dynamics [https://www.youtube.com/watch?v=ez\_9xdZWOcU](https://www.youtube.com/watch?v=ez_9xdZWOcU), [https://www.youtube.com/watch?v=Oe7fYS9qxmk](https://www.youtube.com/watch?v=Oe7fYS9qxmk), [https://www.youtube.com/watch?v=tXnw6nh09N8](https://www.youtube.com/watch?v=tXnw6nh09N8) and in each of these examples it just works for them. They don’t come across any part of the mesh disappearing and just tweak the settings to fit their needs. If the issues I am experiencing are not from settings in my game could it be the way my bones were created for my mesh? If so what is to be expected for the skeletal setup when implementing the Anim Dynamics node? The setup I have is using the simulation space as Component. The bound bone is my upper arm bone (ARM\_L) and I set the Chain End to true with the bone being the hand bone (Hand\_L). The Physics Parameters Body Definitions has 3 array elements. The arm, forearm, and hand. I experimented with the Box Extents for each. The default values are 10. I have increased up to 10000 and even decreased it up to -10000 for each the x,y,z axes. I also changed the gravity amount from it’s default of 1 to .1 because I have a procedural floating animation. I have also removed the procedural floating animation to see if that was interfering with the Anim Dynamics but the mesh will still disappear. I have also set the bound bone to a different bone and that will cause that bone to disappear as well. I even experimented with the constraint setup and the Angular limits. I have set the max to small values like -180 and even higher values like 180. Does anybody know what causes the mesh to disappear? How can I debug this or fix it so that the mesh does not disappear? Additionally, although the section of the mesh disappears the bones do act how I would like them to. In the preview viewport the bones sway along with the procedural float animation. _ **Photo of preview viewport displaying the mesh and it’s bones. The left arm of the mesh is gone:** _ ![image](https://d3kjluh73b9h9o.cloudfront.net/original/4X/4/7/3/473012d3647d068b646e5b0cdbb5e154a32a0ce9.png) _ **Photo of preview without seeing the bones:** _ ![image](https://d3kjluh73b9h9o.cloudfront.net/original/4X/e/3/a/e3ab381c062b865a0a9c0a66bd856a6b54c995c6.png) _ **Photo of mesh in idle without the Anim Dynamics node:** _ ![image](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/a/2/2a2160b0c5cf6209b7bc5c6d03db860d6e073e93.png) _ **Photo of mesh with bones without the Anim Dynamics node:** _ ![image](https://d3kjluh73b9h9o.cloudfront.net/original/4X/a/e/a/aeab9238ff1fafbb6009148f76dd159db5c07a19.png) _ **Changing bound bone to the forearm instead of the upper arm:** _ ![image](https://d3kjluh73b9h9o.cloudfront.net/original/4X/9/7/2/97265773785ba55ced16fa5a34f408623828b5de.png) _ **Anim dynamics setup settings:** _ ![image](https://d3kjluh73b9h9o.cloudfront.net/original/4X/0/a/8/0a8e9d482a9eb34b5ac1f198c25e5aec3c74a26f.png) _ **Physics parameters for Anim Dynamics:** _ ![image](https://d3kjluh73b9h9o.cloudfront.net/original/4X/c/5/0/c50a1ef8b19310d47207be317b9e9f2f447b0267.png) _ **Body Definition settings for an array element:** _ ![image](https://d3kjluh73b9h9o.cloudfront.net/original/4X/8/e/0/8e0c69dd64d1c048a4a6a42395c9977f3b7730ff.png)