I can’t tell you how many hours I’ve put into this stupid coat in the last 3 years (inconsecutively {I give up a lot}). I’ve remade it SOOOO many times. Sometimes the cloth Physics work and sometimes they don’t. I don’t know if it’s my computer or me, but for some reason I’ll get this nonsense. Why does my cloth explode?!?!?!?!?!?!?!?!!?!?!?!?!?!?!!?
The bottom is a different object than the top part and is connected by pin.
My first question/tip is at what scale is the model? Given it’s a person, have you made it at real life size, ie the person is a bit under 2m tall.
In my testing so far I’ve found that the cloth sim just doesn’t have enough precision in it’s settings so once the mesh gets too small (vertices too close to each other) things can start to explode.
The solution is to scale your mesh up (10 times is a good starting point and easy number to work with) and either do everything at that size or export the simulation and apply it scaled down to the original mesh.
Nope. That didn’t do it….
Must be a cloth setting then, it can be surprising how fine a adjust can make all sorts of a difference. Or quality/steps.
Other possibility is collisions, maybe mesh isn’t dense enough and a vertex or two are cutting into the collision object. The moment that happens all hell usually breaks loose.
I assume you applied scale (reset the objects scale to 1) after making it 10 times bigger?
I tried making a cube and applying all of the cloth settings to it and it worked just fine.
I tried scaling it up x20 to no avail, both applying the scale and not.
I tried it on its own in a completely new scene (without any collision objects or self-colisión) No dice.
Eh. Nevermind. I never figured out why it kept betraying me but I just made a new one and it worked fine. 
I’ve done it so many times I’m good at it.
I don’t know if this is why it suddenly worked or not but the first one was made with a cylinder (or cone… don’t remember) but when I remade I, I started with a cube.
Yeah, who knows, the whole simulation system in Blender is rather old and fiddly. It could be one little setting or the random placement of vertices and all of a sudden it’s find.
For that reason I try to keep the ‘cloth’ object as simple as possible, my next usual trick is to just run the simulation on a very simple version of the mesh (one that is high enough density for good simulation) but no extra modelling details at all. Then using a deform modifier I bind that to the actual full cloth mesh, with extra modelling details, solidify modifer, etc.
Is there a tutorial I can follow on this method? I use the solidify modifier, but I don’t really use (or know anything about the deform modifier. How does that come in?
There maybe, but I mostly just figured it out and tested it myself. I’ve had thoughts of somewhat doing a tutorial, more around how I expanded on this method to animate hair. I guess if there’s enough interest I may well give it a go.
But basically, you have 2 objects pretty much on top of each other, run simulation on one and apply that to the other.
So in this first image is the Cloth Sim Mesh, it is nothing more then a subdivided plane, no extra details, no extra modifiers (other then the armature for animation) and as such it deforms fairly cleanly (all at like 10 times real scale).
In the second image you see the actual cloth (what you want to be rendered). This has extra details, the crease down the middle, somewhat like real clothes, is in fact modeled, as is the end part which is like a thicker sleeve or cuff on a shirt. Now yes, you could do this with a texture(bump) map, but it’s just a couple of extra edge loops and highly detailed without having to create and use a 4K image, etc. Of course it could actually be a whole lot more, like a pocket or loops for a belt. Anything that sticks out a little from the main cloth but is near enough that it should still basically deform and move the same.
If you had say that crease on the Cloth sim object, it would just totally fall apart and look like rubbish as part of the simulation, but by using the Surface Deform you can have the higher detail mesh follow the more simple cloth sim mesh and it all looks pretty good.
I used the same method (all be it with a few more levels of complexity) to do a hair test animation.
In this image the three front purple strips are the cloth sim and using weight painting they are more loosely bound to the selected front hair strips which with the surface deform modifier follow the general overall movement.
Only 2 cloth sims objects are used to then control all the hair objects and of course only the hair objects are actually rendered.
Here’s how it all looks as an animation:
Wait wait wait wait wait… You did that second image without any cloth physics?
Oop. Nvm. I reread more carefully. That’s pretty impressive. I’ve bweb spending so much time trying to perfect my cloth physics knowledge. I need to learn that other deform modifier
Well, your in luck, I’ve recently done a bit more of an overview for some cloth simulation. It doesn’t directly cover the hair, but it does discuss pretty much all of the techniques that I did use in order to animate (simulate) the hair.
Hopefully you find it of some use.
Listen. It took me a while to get it,… (still learning a bit) but this has been a life changing lesson. Thank you for showing me this.
Nice to hear it’s been of help, cheers.
