Hi, so i created a tail skeletal mesh around a year ago in UE4.26 pretty much using this tutorial as the basis Ponytail physics Tutorial in Unreal Engine 4 - YouTube except obviously a tail instead of a ponytail. This worked fine in ue4.26 and ue4.27 since upgrading to ue5 the tail now gets stuck at random times quite often when spawning and the skeletal mesh will stretch from the stuck tail to the skeletal mesh/character it is attached too, the stretching looking at the physics asset appears to happen on the simulated body after the body with the default physics type. As far i can tell this happens randomly maybe 2/5 times. Seems like a bug but i canât find anybody else reporting this
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Iâm having a similar problem where my tail grows/stretches when i spin. Did you find a solution? I also followed that tutorial.
No unfortunately i didnât find a solution for my problem i assume itâs a bug, hopefully itâll be fixed in 5.1, The stretch can be reduced by playing around with the physics settings; i think on the attached skeletal mesh in the blueprint thereâs a few settings in there like dampening which will help i believe, theres also a ton of settings which can effect this on the physics asset. Iâve managed to reduce the normal stretching when moving mostly but if for whatever reason the character moves really fast then it will still stretch temporarily.
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This happens because the skeletal mesh physics bodies set to simulate will go to sleep, and because the simulation had stop, it will remain behind in place.
There are two ways to fix this.
The first one is the hacky way which will work fine, but not sure about performance impact. On tick you add a delay node, just to avoid running any frame, and you add this âReset All Bodies Simulate Physicsâ node. Off course you need to target your character skeletal mesh component
The second solution is the proper way, but unfortunately I donât know the precise settings that you need to use. I didnât found anyone explaining how to use this, most assume the behavior you have explained is a bug, which is not, and they use the hack way.
No one knows how to use it and for some strange reason unreal team forgot to explain how to do it properly. Or maybe they did explained but we all missed the explanation.
If someone from unreal see this can you please explain how to set these settings correctly, some of us want to create breast physics correctly. is the only reason we have learned all this complex stuff from unreal and then, when we got to the point of what we want to do, we get this âbugâ 
So inside the âPhysics Assetâ when selecting the physics bodies that is set to simulate, you need to create and add a proper physics material.
If you add the material with correct settings the physics bodies will not go to sleep anymore. All physics bodies set to simulate needs to have a physics material
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I tried the first method you mentioned and that doesnât work and the second one i doubt works either as this shouldnât effect the issue i mention, i think perhaps your experiencing a different issue either way seems like a bug in UE5 as i donât remember this happening ue4
this is a UE5 thing. both method works. you most likely did not implemented the methods properly or you have a different issue as you have said
ye i have the issue which i created this post about - attached skeletal meshes, i tried your methods and they do not work, not sure how you can implement them incorrectly but again the issue your talking about seems different or your solutions do not work
I can confirm that the above methods do not work. Iâm dealing with the same issue- I have a tail with a rigidbody simulation that likes to fall asleep and get stretchy until its manually poked.
Yes, itâs so hacky but I havenât found another solution. I had exactly the same issue: the simulating bodies of my characterâs physics asset (the tail) just stayed static and were left behind, with massive stretching to my meshâs body moving around the level. It looked awful.
I tried both the solutions here. Surprisingly, the custom physical material on all of the simulating bodies worked with the following settings. It seems that it works by not allowing the simulating bodies to sleep. Surely there is a better way though.
By the way, this might also be useful, hereâs a recent physics dragon tail setup on the official channel in the middle of this video.
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I started working with the 5.1 (preview) and was able to remove the hacky physical material workaround. It seems to work as expected now. Fingers crossed 
Just one more data point for the pile:
I also followed that pony tail tutorial with ue4 and in ue5 ragdoll bone chains often stretch like crazy especially during fast animation or when I teleport the player. And also often ragdoll pouches on the belt would be left behind in mid air.
I tried the physics material trick and it did not work for me. Fingers crossed for 5.1
thanks a lot,it troubles me for a long time,simulate go to sleep is the reason 