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so I am a beginner at blender. I am currently making clothes for my character and I ran into a problem. So I have a some kind of tie, and I'm trying to simulate it. When I bake the simulation it "cripples". I don't have an idea how this happens, any help would be appreciated.blender fileenter image description here

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    $\begingroup$ Most likely due to self-collision or starting in collision with another mesh. Try disabling Self Collision and see if that helps. $\endgroup$ – Rich Sedman Mar 19 at 11:30
  • $\begingroup$ Thanks, that works! But now how do I make my tie collide with my shirt? If I add collision physics to it my tie cripples again $\endgroup$ – Uhmzzzzmmmm Mar 19 at 11:57
  • $\begingroup$ Try 'Apply Scale' on each of your meshes. Then reduce the 'Outer' distance of your Collision on your mesh and check your normals . Most likely you've got the meshes too close to each other or intersecting at the start of the animation, messing up the collision right from the start. One thing to try is to move them further apart and run the simulation to ensure it's working fine without them being so close then bring them together to see where the problem starts occurring - this will help you troubleshoot the actual issue causing the problem. $\endgroup$ – Rich Sedman Mar 19 at 12:38
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    $\begingroup$ Check your normals of the collision mesh - if they’re in the wrong direction then any collision will grab and drag the cloth vertices into the mesh. $\endgroup$ – Rich Sedman Mar 19 at 13:12
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    $\begingroup$ Yes - probably best to share the file. Can you upload it to blend-exchange and edit your question to include the link to it. $\endgroup$ – Rich Sedman Mar 20 at 11:16
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A large part of the problem here is with collisions and the boundaries of collisions. This is resulting in some of the meshes being effectively intersecting at the start of the simulation - or becoming trapped below the surface part way through the simulation - which is then dragging the surface into the mesh in an unpredictable manner.

The first thing to change is the collision on the button meshes - these are hooked onto the front of the shirt and have their own collision settings. This is having two effects - one is that it is interferring with the shirt itself (since it is pinned to the surface and is also colliding with the surface it is causing a conflict in the forces that result). Since the buttons are small and should not significantly affect the simulation it is easiest to simply remove the Collision from all of the buttons.

Secondly, I noticed that the 'neck' section of the tie is getting dragged under the surface of the shirt at the start of the simulation. This is a sign that the meshes are starting the simulation effectively already intersecting. While they don't appear to be intersecting, the collision settings (in the Collision physics modifier and also the Cloth settings themselves) include 'bounds' that can extend beyond the mesh surface. When diagnosing such issues it is a good start point to change those bounds (the Inner and Outer settings in the Soft Body and Cloth settings of the Collision settings and the 'Distance' in the Cloth Collision settings). Note that as soon as you get one cloth vertex dragged below the surface of a collider, it can result in more of the cloth being pulled through the mesh.

Once the above changes had been applied I re-ran the simulation with a much better result. Any further discrepancies should be able to be resolved by ensuring the meshes start slightly further apart in the problem areas, by reviewing your geometry to avoid large variations in edge lengths (areas of cloth where the vertices are close together will behave differently to those where they are further apart) and I also noticed that the tie itself is made up of two layers of faces - it would be better to model as a single surface and then add a Solidify modifer to give it thickness.

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  • $\begingroup$ Ok, so i tried to remove the collisions on the button but I can't get the proper result because somehow my clothes explodes now imgur.com/a/HMbcom5 (Nothing pinned and self col is off, have tried to remove the body but still explodes) does it explodes on your side? or maybe its because I'm using an older version of the shirt? also can you explain about what the "two layers of faces" mean and are there any values I should change in the cloth sim settings, Thanks! sorry if you're bothered. $\endgroup$ – Uhmzzzzmmmm Mar 24 at 23:37
  • $\begingroup$ I did get some weird effects which was why I disabled the collision on the buttons as I'd tracked it back to there. Just to be sure, try deleting the buttons to ensure they aren't present at all. Also, ensure you change the Outer and Inner on all of your mesh's collision settings to as low as it can go and also turn down the Cloth Collision Distance. 'Apply Scale' to each of your meshes. If you're still getting problems, try separating the meshes to determine whether there is anything overlapping at the start of the simulation. I managed to get it successfully simulating. $\endgroup$ – Rich Sedman Mar 24 at 23:53
  • $\begingroup$ The "two layers of faces" is referring to the way the tie is made up of separate 'front' and 'back' faces rather than being just flat planes with no 'thickness'. For cloth it's generally better to simulate without thickness and to add that later with a Solidify modifier that's after the Cloth modifier in the Modifier Stack. $\endgroup$ – Rich Sedman Mar 24 at 23:54

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