first of all thank you all for all the effort that everyone make answering questions and solving other people problems :)

I'm quite new in blender, I've started using it during the summer, following all the tutorials that I've found on youtube. I've started with the "classic" donut tutorial, and with some simple animations, and just few days ago I've approached the "physics simulation". Everything started with the "couch tutorial" where Andrew suggest how to model pillows using the physics simulation (link here). Unfortunately something is going wrong (as from the picture below). ![enter image description here

Now, I'm not sure about the origin of the problem, however I've an idea. It seems to me that the computer is trying to simulate everything too fast, and doing so it skip passages or frames and make errors, causing impossible situation in the simulation. The idea of this came to me when I saw this in the timeline, as if some frame were correctly calculated and other no: enter image description here

This behavior happens also in other occasion when I've tryied to make some liquid simulation.

Since this, I'm wondering if in your opinion this could be the problem and if there is a way to tell Blender "take your time to run the simulation, there is no hurry".

As suggested, I'm also attaching here the blender file.

Thanks a lot to everyone will try to help me.



PS: the PC that I'm using for this simulations in not the best but is working fine in general for my needs: [Intel(R) Core(TM) i5-10210U CPU @ 1.60GHz 2.10 GHz, RAM 8,00 GB, SO Win 64 bit]

PPS: I've tryied to look around to see if someone already had this problem, but I wasn't able to find anything, with the exception of how to slow down simulation speed (but not hot to force to simulate all the frames or something similar). In case I missed something around, just let me know. Thanks.

  • $\begingroup$ normally tutorials work, but you have to do exactly(!) what the tutorial says. Don't use another method. Don't do other things in between. This is all can change the result. just an example: scaling in edit mode and scaling in object mode make a huge difference in the result (if you don't apply scale afterwards) and we all made these mistakes. So i would suggest: start from scratch and try to follow every single step. Since you don't link the tutorial and you didn't provide your blend file it's nearly impossible to help you because we can just guess what the reason might be... $\endgroup$
    – Chris
    Commented Dec 11, 2021 at 15:49
  • $\begingroup$ Thanks Chris for your fast answer. As suggested I've highlighted the link of the tutorial and added also a link to download the .blend file. $\endgroup$
    – Tommaso
    Commented Dec 11, 2021 at 16:05
  • $\begingroup$ Also note that too often tutorials do not state which version of blender they work with, and often updates to blender "break" the tutorial as you then have to figure out the updated way of accomplishing the workflow. $\endgroup$
    – james_t
    Commented Dec 11, 2021 at 17:51

1 Answer 1


You haven't reduced the VertexMass under PhysicsProperties as he talks about from around 1:10 in the tutorial. Reduce it from 0.3kg to 0.01kg as he shows at 1:25.

enter image description here


You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .